DWYER APRIL 9, 2010jcole/FRep.pdfsmall all‐terrain vehicle, capable of navigating rough terrain and water obstacles, typical of a rural NL location. Basic vehicle specifications

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8936

Mechanical Project

MATV: Memorial All Terrain Vehicle

FINAL REPORT

JONATHAN COLE FABIO FARAGALLI TREVOR DWYER

APRIL 9, 2010

FINAL REPORT MATV

8936 Mechanical Project – MATV Page i

Table of Contents

1 Introduction ..........................................................................................................................................1

1.1 MATV Specifications ....................................................................................................................1

1.1.1 Platform...................................................................................................................................1

1.1.2 Drive‐train ...............................................................................................................................2

1.1.3 Controls ...................................................................................................................................3

2 System Design .......................................................................................................................................3

2.1 Hydraulic Design ..........................................................................................................................3

2.2 Hydrostatic Transmission ............................................................................................................3

2.3 Gasoline Engine ...........................................................................................................................4

2.4 Platform.......................................................................................................................................5

2.5 Drive Shaft Design .......................................................................................................................7

2.6 Drive Train Component Selection................................................................................................8

2.7 Suspension Design .......................................................................................................................9

2.8 Wheel and Hub Design ................................................................................................................9

3 Finite Element Analysis ....................................................................................................................... 10

3.1 Suspension Members ................................................................................................................10

3.2 Drive Shafts................................................................................................................................13

4 Weight Estimate..................................................................................................................................14

5 Cost Estimate ......................................................................................................................................16

6 Project Deliverables ............................................................................................................................17

7 Recommendations and Conclusions ...................................................................................................17

Appendices

Appendix I – Sauer‐Danfoss BDU‐21H Appendix II – Honda GX690 Appendix III – Technical Drawings – Frame Members and Mounts Appendix IV – Technical Drawings – Drive Shafts, Gears, and Bearings Appendix V ‐ Technical Drawings – Suspension, Wheels & Hubs Appendix VI – McMaster‐Carr Technical Drawings

FINAL REPORT MATV

8936 Mechanical Project – MATV Page ii

Figures

Figure 1: MATV Inner Frame.........................................................................................................................5 Figure 2: MATV Transmission Mount ...........................................................................................................6 Figure 3: MATV Suspension ..........................................................................................................................6 Figure 4: MATV Upper Driveshaft .................................................................................................................7 Figure 7: Displacement 20kN load ..............................................................................................................10 Figure 8: Strain of 20 kN load......................................................................................................................11 Figure 9: Displacement of 10 kN load .........................................................................................................12 Figure 10: Strain of 10 kN load....................................................................................................................12 Figure 11: Displacement momentum force ................................................................................................13 Figure 12: Strain momentum force.............................................................................................................14 Figure 13: MATV Weight Estimate..............................................................................................................15 Figure 14: MATV Fuel Calculation...............................................................................................................15 Figure 15: MATV Cost Estimate ..................................................................................................................16

FINAL REPORT MATV

8936 Mechanical Project – MATV Pg 1

1 Introduction

Project MATV began as a suitable Term 8 design project for a group of students in search for an

interesting and challenging senior project. The project has undergone a number of large design

iterations, and currently has the potential to grow into a faculty oriented, multi‐disciplinary design

project incorporating autonomous controls into a mechanically sound vehicle design.

At this point in time, Project MATV is at the end of its 3rd design iteration of the term, and of the project

as a whole. This paper will serve to document the current design package developed for Project MATV,

and provide recommendations for its potential future development.

The introductory section of this paper is written with an unfamiliar audience in mind to account for

potential future project groups, while the detailed section of this report is written with the assumption

that the reader has some knowledge of the project, as outlined in the introductory section and

supporting documentation.

1.1 MATV Specifications

Design specifications for project MATV have stayed relatively constant during the entire design process,

despite the large changes in drive train orientation and basic power train. The MATV is essentially a

small all‐terrain vehicle, capable of navigating rough terrain and water obstacles, typical of a rural NL

location. Basic vehicle specifications include six independently sprung wheels utilizing a skid‐steer

system, and a water‐tight main platform with ample room for controls equipment, navigation

equipment, cameras, and other required cargo. Performance specifications are laid out to ensure the

vehicle can navigate unforeseen obstacles at full design weight.

1.1.1 Platform

Original design specifications for the platform include a weight restriction, a size restriction, and some

functional usability restrictions. The original weight restriction for the entire vehicle was 300lbs plus a

payload of 50lbs. This restriction has been one of the more difficult specifications to deliver throughout

the project, and has prompted at least one of the overall design iterations for the project. The major

issue with the weight restriction has been that components able to support the vehicles performance

specifications are often much heavier than the 300lb weight restriction allows.

FINAL REPORT MATV


One recommendation for the future development of this project is a closer look at the weight

restrictions in relation to the performance restrictions. A general trend has been that light weight

components cannot support the performance specifications, while heavier components are essentially

overdesigned for both the performance and weight specifications. Although sometimes difficult to

grasp in a design project, component availability often governs design specifications when attempting to

work under budget constraints.

The initial size restraint for Project MATV was simply the ability to fit through an “average” sized door.

When defining an average sized door as an exterior door or industrial sized door, typical of the

university for example, a rough assumption can be 36”. During the first design iteration at the beginning

of the term, this width was increased to 48”, to allow for the larger hydraulic components and a‐arm

suspension concept.

Initial ground clearance specifications allowed for the ability to climb stairs. This figure was quantified

with the first design and increased to 12‐14” to allow for navigation of larger obstacles. Throughout

design, the six wheel vehicle with skid‐steer concept has been maintained.

Physical platform dimensions have not been restricted during design, with the exception of the overall

vehicle width and weight restrictions. The internal cargo space available for equipment however, has

been restricted to 2ft3 or greater regardless of vehicle design.

1.1.2 Drivetrain

Initially the MATV was envisioned to utilize an electrically powered drive train with electric batteries

driving dual electric motors, chain driving the 6 independently sprung wheels. This concept was

amended during the first project redesign to allow for a hydraulically powered drive train. Although the

hydraulic system has undergone two design iterations, specifications have always included a gasoline

engine powering the hydraulics, which have mechanically powered the wheels.

Power specifications have evolved from the requirement of the vehicle to climb stairs, to the

requirement for the vehicle to lift its front wheels up a vertical obstacle (model 30° slope), to finally

requiring the vehicle to climb a 45° slope at full design weight. The maximum design speed for the

vehicle has remained constant at 30km/h.

FINAL REPORT MATV


1.1.3 Controls

During initial proposal of Project MATV, the vehicle was to operate under remote control initially, with

potential future expansion for autonomous control. Throughout the course of this project, design

deliverables for the term have shifted from a functional prototype to a complete virtual design package.

As such, control of the MATV has not been included in this design iteration, and is recommended as a

future component of the project.

Autonomy period has been specified during the project as 24 hours. This period is governed by the

amount of fuel that the vehicle carries, and the amount of fuel that the engine consumes per hour. Fuel

volumes have been specified with the design package, but have not been included in operational weight

calculations, as per recommendation from the instructor, and to account for the constantly changing

volumes with engine specification.

2 System Design

2.1 Hydraulic Design

A hydraulic system regression analysis and justification for the selection of system operating pressures is

outlined in “Mini Report #2” of the Project MATV design documentation. System operating pressure is

the largest variable affecting hydraulic system performance, and as a general rule, selecting the highest

supported continuous operating pressure for hydraulic components will result in greatest performance

from the hydraulic system. Operating pressure for the current system design is 3250psi, which falls

between the specified continuous and maximum operating pressures for the BDU‐21H Sauer‐Danfoss

hydraulic transmission.

2.2 Hydrostatic Transmission

The hydrostatic transmission selected for the current design is the Sauer‐Danfoss BDU‐21H. Previous

selection of the Sauer‐Danfoss 15 Series In‐line transmission was superseded with this unit, as the 15

Series transmissions have been discontinued.

FINAL REPORT MATV


The maximum theoretical output of this transmission is 72.1 N ∙ m. We have calculated the real output

torque of the transmission to be 63.6 N ∙ m at the 3250 psi system operating pressure. The weight of

this unit is 22 lbs, and the specified control torque for maximum pump stroke is 24.5 N ∙ m. Full

specifications for the Sauer‐Danfoss BDU‐21H are located in Appendix I of this report.

Throughout the term, we have maintained contact with a local Sauer‐Danfoss supplier, Hydraulic

Systems Limited. It is worth noting that this company is also a local supplier for Parker Hydraulics Ltd., a

product that had previously been specified for the Project MATV independent wheel motors, as part of a

previous design.

The contact for this supplier, for future Project MATV reference is:

Jim Maloney Technical Sales Representative Hydraulic Systems Limited e: jmaloney@hydraulic‐systems.com Ph: (709) 726‐3490 Cell: (709) 726‐3490 Fax: (709) 726‐3490

Unfortunately, this supplier has not delivered a quote for the BDU‐21H units at this time. Following up

on the original request is recommended if the BDU‐21H units are to be used.

2.3 Gasoline Engine

Due to the control torque requirements of the BDU‐21H units, a gasoline engine with suitable output

torque had to be selected. The selected engine was to provide enough torque to stroke both

hydrostatic transmissions, and would preferably be a unit with published performance specifications

and dependable quality. The selected unit was the Honda GX690 horizontal shaft V‐twin engine.

This engine has a net torque of 48.3 N ∙ m at 2000 rpm and a net power of 22.3 Hp at 3600rpm. Due to

the v‐twin design, we don’t see a large torque drop over the range of operational rpm, and net torque at

3600 rpm is approximately 44 N ∙ m. The weight of this unit is 98 lbs, and fuel consumption is 6.2 L/hr at

3600rpm. Full specifications for the Honda GX690 are located in Appendix II of this report.

Early in the term, contact was made with a supplier of Honda small engines for Atlantic Canada. Initial

contact was made via telephone conversation, and some important contact information was obtained.

FINAL REPORT MATV


The name of the company contacted is “Powerquip A Division of Barrett Marketing Group”, located in Dartmouth, NS. The company was contacted through their published toll free number ‐ (800) 662‐2920. An individual named David spoke with us, and provided an e‐mail contact for future reference ‐ [email protected].

This company indicated that they have a program in place that allows for the donation, or significant

discount on small engines for recognized university projects. At the time of contact, David suggested

that Project MATV submit an official letter of project recognition on university letterhead once an

engine model was selected, and he would see what applicability the program would have for our

project. As the engine choice for Project MATV changed a number of times throughout the term, and no

set purchase plan for components was outlined, Project MATV did not submit a request for official

engine quotation.

It is recommended that Project MATV contact this supplier for quotation and program applicability if a

Honda series small engine is used for the project.

2.4 Platform

Figure 1: MATV Inner Frame

The frame shown above is constructed entirely of 80/20 extruded aluminum, which was chosen for its

high strength to weight ratio. Shown in appendix III is an exploded view detailing each component used

to make the frame and the number of times it is required.

FINAL REPORT MATV


Modifications may need to be performed to each component in order for the frame to be assembled.

80/20 has a few options for fastening each piece together, depending on which option is chosen will

determine if the part needs to be altered. The alterations a relatively simple and would be the same for

each member, therefore the machining process will be simple to perform.

Mounting the transmission will be accomplished with mounting bracket shown below; it will be

machined from 316 stainless steel to ensure corrosion resistance. There are four holes drilled in the

bottom that will allow for attachment to the 80/20 frame. The two holes on the side are for the two

fastening rods that will hold the transmission in place. The fastening rods are black‐oxide steel spacing

stud M8X1.25mm, 200mm in length with 35mm thread lengths at either end.

Figure 2: MATV Transmission Mount

The shocks will be held by two mounting brackets, one on the swing arm and the other on the frame as

shown below. These brackets will be machined from 316 stainless steel same as the transmission

bracket and will have measurements specified in the drawing “Swing Link” under Appendix V.

Figure 3: MATV Suspension

FINAL REPORT MATV


2.5 Drive Shaft Design

For the drive shafts we recommend using 1566 high carbon steel for its high strength and ability for

machining. We discovered this material through cooperation with another group (Mini Baja) and they

have done extensive stimulations on the material and it meets the requirements for our design. In total

there will be 10 separate drive shafts machined, however due to the symmetry of the MATV there are

only three different shaft designs. The bearings and sprockets are listed in the attached part list (cost

estimate), and all can be supplied through McMaster – Carr.

Figure 4: MATV Upper Driveshaft

The first shaft which we have named “Drive Shaft” is shown above in and will drive the front and rear

wheels, as seen in the appendix IV as drawing “Drive Shaft” the shaft is ¾” in diameter with a step down

at either end to 5/8”. The shaft is 11 ¾” in length with two keyed slotted sections 3/16” wide and 3/32”

in depth to allow for the key for the gears. The two steps allow for a place for the bearing to butt

against and each end is threaded to secure the bearings and therefore the shaft in place.

The second shaft designed for the center wheels is referred to as “Drive Shaft – Center” and has a

similar design of that of the “Drive Shaft” the only difference is that the center shaft attaches directly to

the wheel which causes it to be longer to ensure all the wheels are in the same plane. The “Drive Shaft‐

Center” ” is attached in appendix IV is 13.88” long and is threaded ½” at the end attached to the bearing

and 1.32” at the end that attaches to the hub. The additional threading is for the threaded hub. The

“Drive Shaft – Center” also only has one keyed section due to the fact it does not require an outer gear.

FINAL REPORT MATV


The third shaft, which is titled “Shaft of Wheel”, is the shaft that is connected to the front and rear

wheels and is driven by the “Drive Shaft” through a chain. The shaft is 6.88” in length and has a single

step for the bearing to butt up against and hold the assembly in place. The “Shaft of Wheel” shown in

the attached appendix IV is keyed a single time at the ¾” end in order to support the gear that drives the

shaft.

2.6 Drive Train Component Selection

When choosing the gears for the drive train we first calculated the required torque at the wheels, from

this we determined the necessary gear ratio and holding force at each shaft. Also due to the complexity

of our shaft design we choose to use gears that could be mounted to our shaft via a single key and

tapered design. The shaft itself remains straight however the gear comes in two sections as one is

secured to the other it forces the bore diameter to restrict tightening it on to the shaft. Copies of the

McMaster‐Carr technical drawings are attached in appendix VI.

For the chain selection we used the data gathered for the gears and knowing our working load we

choose a chain that meet the force requirements, we went with the corrosion resistant chain due to our

application. For the bearings we actually ended up using backwards engineering, we had an idea of how

we wanted to mount the bearings and what style bearing would work best. For the bearings that would

sit inside the frame we wanted to use pillow block style bearings which would mount easily to our 80/20

frame, for the bearings that would mount to the swing arm we opted to use flange mount and as

mentioned later the swing arm selection was dependant on the surface area required to mount the

bearings.

We had only chosen to use one flange mount bearing per shaft but after speaking with our supervisor,

we were asked to use an additional bearing which he thought would give the rigidly required to support

the arm. With these general specifications and the shaft diameter we were able to narrow the search

down dramatically leaving just a few choices left and we opted to take the least expensive which also

turned out to be the bearing capable of with standing the greatest radial load. Knowing all the

specifications of the bearing we calculated what load it could with stand and it was far more than what

we would require. The technical drawings and bearing specifications are attached in appendix VI.

FINAL REPORT MATV


2.7 Suspension Design

Initially we had decided to use an A‐Arm suspension design, which would have worked fine with the six

independent motors. However when we had to re‐design in order to save weight and cost the swing

arm design became more practical. The chain drive requires the “Drive Shaft” and “Shaft for Wheel” to

remain a set distance apart, this is easily accomplished with the swing arm design. As seen in Figure 3,

there are two mounting brackets that hold the shock, one attached to the swing arm and the other to

the frame. The shocks which we have found online at eshocks.com have 5.33" travel and an extended

length of 16.45". The mounting brackets which have been mentioned earlier will have to be machined

and a detailed drawing provided in appendix V. Initially we thought of using tube steel or aluminum for

the swing arm but to reduce overall size and weight we opted to use aluminum U‐channel, which we

found online at Online Metals.com. The U‐Channel provides enough surface area to mount the required

bearings and by running the chain on the inside we hope to help protect it from any obstructions.

2.8 Wheel and Hub Design

When choosing the wheel initially we had set an overall diameter of 12”, after some research we

decided to increase our diameter to 16‐18” this would help ensure we met our clearance parameter.

Wanting to keep cost and weight to minimum as well as ease of attainment we sourced princess auto.

They had and still have a 16” overall diameter wheel and rim retailing for $39.99, this was lower than

any other product we had sourced and because it was local would negate any shipping cost. Checking

the specifications of the wheel we found it was rated for more than an adequate weight and weighing

only 9.7lbs each it was perfect for our project. With the rim chosen we were able to limit our search for

a wheel hub, knowing both the shaft diameter and bolt pattern we were able to find a suitable hub at

mfgsupply.com. The hubs are made of steel and weigh only 1.5 lbs each and with a low cost of only

$19.99 each they are more than adequate for the project.

FINAL REPORT MATV


3 Finite Element Analysis

3.1 Suspension Members

The suspension members are most important to the vehicle when it is traveling at high speeds. Several

testing has been completed in SolidWorks to demonstrate if the MATV could undergo loads and see if

they can support such forces in rough terrain. Axial loads were the main forces that the suspension

would be subject to. The FEA analysis of 20 kN and 10 kN forces have been tested.

Shown in the figures below, the FEA analysis illustrates the suspension member that is subjected to a

static loading on the wheel. The pillow bearings are attached to the frame which gives a restrain onto

the movement of the bearings and the entire assembly. A force is applied to the wheel, when the

vehicle falls from a certain height, an example of this is when the rover would fall into a ditch. The

assembly that was test could not support the complexity of the mounted bearings onto the swing arm

therefore testing without these bearings was obliged.

The first test was done at a vertical force of 20 kN simulating a great load onto the wheel shaft and

swing arm. Figure 57 illustrates the displacement of the entire wheel assembly when subjected to a

load of 20 kN. The results of the displacement of the wheel shaft are 2.31 inch, which is standard for an

immense load onto a light and thin swing arm.

Figure 5: Displacement 20kN load

FINAL REPORT MATV


The strain results shown in Figure 68, demonstrates that the pillow bearings and swing arms are

subjected to stress and deformation. The stresses applied to the swing arms are absorbed by the

mounted square bearings that would be attached to the swing arms therefore the stresses on the

member would be diminished. This also would allow to a smaller displacement of the assembly. The

greater stresses occur on the upper portion of the swing arm due to the greater moment forces. The

maximum strain on the suspension member is on the bearings where it indicates a strain of 1.64 ESTRN.

Figure 6: Strain of 20 kN load

The second test was done at a vertical force of 10 kN this simulates a real situation loading. Figure 79

illustrates the displacement wheel shaft and swing arm. The results of the displacement of the wheel

shaft are 0.8 inch; this is relatively low for a force of 10 kN on a swing arm of 3/16 inch. The maximum

displacement is situated at the wheel. This force applied does not plastically deform the members

therefore the components chosen would be able to support loads that would be subject to in a rough

Newfoundland terrain.

FINAL REPORT MATV


Figure 7: Displacement of 10 kN load

The strain plot demonstrates the maximum strain of the suspension members. In Figure 810 the

maximum stress that is applied is located at the swing arm, this is due to the thin thickness of this

member. Although, the stresses that are subject to the member is absorbed by the bearings that are

located and the upper and lower section of the swing arm. Therefore, minimal stress is acted on the

member.

Figure 8: Strain of 10 kN load

FINAL REPORT MATV


3.2 Drive Shafts

The force acting on the drive shaft member can also be viewed as a momentum force, where the MATV

is traveling at maximum velocity and hits an obstacle where the MATV will come to rest. This force is

calculated by the momentum equation:

F = (m * v) / ∆t

m = mass of vehicle

v = velocity

∆t = change in time for the vehicle to come at rest

The diagrams below illustrate a load applied vertically, although the momentum force is applied to the

member horizontally. This does not affect any results in this section due to symmetry of the member.

The force of momentum calculated is ~ 10,000 N where the time of impact is 0.25 sec. The diagram

below indicates the restriction of the bearings and applied load. Figure 911 show the displacement of

the drive shaft where the maximum displacement is 0.70 inch, this is the result of the MATV traveling at

a speed of 30 km/hr.

Figure 9: Displacement momentum force

The strain plot of the momentum force demonstrates the maximum strain of the suspension members.

Although, the strain applied to the member is minimal, the maximum strain is 3.9 *10‐7 situated at the

pillow bearings. This test demonstrates that the forces of momentum do not plastically deform the

drive shaft and therefore the components chosen will be able to sustain great loads.

FINAL REPORT MATV


Figure 10: Strain momentum force

4 Weight Estimate

A weight estimate for Project MATV is outlined below. As mentioned, the initial weight specification for

the project was 300lbs plus a 50lb payload. During the 2nd project iteration, a regression analysis

supported the suggestion that a total vehicle weight of 500 lbs was more realistic, and easily supported

within the selected component performance limits.

Although the current components can easily support a weight of 500lbs or more, the design weight of

500lbs has been used as a benchmark for all final design calculations. As the system components

currently selected for this project are well overdesigned and can support well over 1500 lbs +, weight is

not a large concern for system design, however a modest 500 lb weight has been designed for.

As mentioned earlier in this paper, fuel volume and weight have not been taken into consideration

during this design. The justification for this was the changing specifications for engine fuel consumption

with engine sizing.

The group had identified fuel weight and volume as a large variable for design, and a large weight issue

within design, so by recommendation from the project supervisor, the current design was completed

without consideration for fuel weight.

FINAL REPORT MATV


Component Description Unit Weight Quantity Weight (lbs)Engine Honda GX 690 98.0 1 98.0Transmissions Sauer-Danfass BDU-21H 22.0 2 44.0Transmission Bracket Bracket machined to hold transmission 4.0 2 8.0Steel Spacing Stud Black-Oxide Steel Spacing Stud M8X1.25mm 0.3 4 1.0Steel Hex Nut Metric 18-8 Stainless Steel Hex Nut M8 Size, 0.1 8 0.4Timing Belt Pullies 1.5 2 2.9Timing Belt 2.0 1 2.0Mating Shaft (trans) 2.0 1 2.0Chain Gears Single-Type QD 5.12" OD 3.0 2 6.0Chain Gears Single-Type QD 4.52" OD 2.5 4 10.0Chain Gears Single-Type QD 2.09" OD 2.0 14 28.0Chain Standard ANSI Roller Chain #50, Single Stran 0.7 30 20.7Roller Chain Links #50 Adding Link for Standard ANSI Roller Ch 0.0 20 0.5Wheels/Tires 16" Overall Diameter Wheel 9.7 6 58.0Swing Arms Aluminum Bare Channel 6061 T6 1.9 5 9.3Axle (Inches) 60" Keyed 3/4" diameter shaft 0.2 120 25.6Hex Nut 5/8" Ultra-Coated Grade 8 Steel Hex Nut 5/8"-18 T 0.1 16 0.8Shocks 5.33" travel 16.45" extended length 8.0 4 32.0Square 80/20 (inches) Extruded Aluminum 1"X1" 0.026 838.6 22.180/20 Connectors Connectors for Extruded Aluminum 1"X1" 15.0Bearings - Pillow 5/8" Base mount double sealed bearing 3.0 6 18.0Bearings - Pillow 3/4" Base mount double sealed bearing 3.0 6 18.0Bearings - Flange Mount Flange mount double sealed bearing 3.0 16 48.0 Al Sheet (Body) 32"X74" 1/16" thickness 15.0 1 15.0 Al Sheet (Body) 26"X54" 1/16" thickness 9.0 1 9.030L Gas Tank Dimensions (cm) 90X20.5X26 6.6 1 6.64L Hydraulic tank 1.0 1 1.0Hydraulic Fluid (Litres) Type F Automatic Transmission Fluid 1.9 4 7.6Hubs Steel Hub for 5/8" live axle 1.5 6 9.0

Total Weight 518.4

MATV Weight Estimate

Figure 11: MATV Weight Estimate

The specified weight of 518 lbs is very close to the design weight of 500 lbs, and was just pushed over by

the additional flange mount bearings recommended for the outside of the swing arms, and the extra

weight of the Honda GX690 engine.

As a note, the calculation for fuel weight and volume with this particular engine is as follows:

Engine Consumption 6.2 L/hrAutonomy Period 24 hrGasoline Specific Gravity 42.5 lb/ft^3Conversion 28.32 L/ft^3

Fuel Volume = (6.2 L/hr)*(24hr)Fuel Volume = 148.8 L

Fuel Weight = (148.8 L)*(42.5 lb/ft^3)/(28.32 L/ft^3)Fuel Weight = 223.3 lb

Figure 12: MATV Fuel Calculation

FINAL REPORT MATV


The fuel weight for a 24hr autonomy period with the Honda GX690 engine is just under 50% of the total

vehicle design weight before fuel. This is a significant increase in weight, and as such, is viewed as a

critical design variable for project design. This variable alone warrants a closer look at system sizing and

desired performance specifications versus system weight for engine sizing.

5 Cost Estimate

A cost estimate for Project MATV is outlined below. An analysis of this estimate shows that over 50% of

the estimated cost of the project is for the engine and hydrostatic transmissions alone. In addition,

these prices represent list prices, not accounting for things such as taxes, conversions, shipping, etc.

The project team was not happy with this final cost estimate, as it is higher than we would have wanted

a project such as this to total. It is recommended that a system redesign (if required) look at smaller

components that may satisfy performance specifications on a smaller scale for both weight and cost.

Component Description Supplier Part Number Unit Cost Quantity Cost ($)Engine Honda GX 690 Brand New Engines $1,495.00 1 $1,495.00Transmissions Sauer-Danfass BDU-21H Hydraulic Systems Ltd. $1,500.00 2 $3,000.00Transmission Bracket Bracket machined to hold transmission Tech Services $100.00 2 $200.00Steel Spacing Stud Black-Oxide Steel Spacing Stud M8X1.25mm Sz, 200mm L, 35mm & 35mm93275A038 $3.61 4 $14.44Steel Hex Nut (pkg 50) Metric 18-8 Stainless Steel Hex Nut M8 Size, 1.25mm Pitch 91828A410 $9.98 1 $9.98Chain Gears Single-Type QD 5.12" OD McMaster-Carr 2500T791 $53.75 2 $107.50Chain Gears Single-Type QD 4.52" OD McMaster-Carr 2500T761 $43.29 4 $173.16Chain Gears Single-Type QD 2.09" OD McMaster-Carr 2500T632 $18.03 14 $252.42Chain Standard ANSI Roller Chain #50, Single StranMcMaster-Carr 7210K323 $489.50 1 $489.50Roller Chain Links #50 Adding Link for Standard ANSI Roller Ch McMaster-Carr 7210K325 $1.76 20 $35.20Wheels/Tires 16" Overall Diameter Wheel Princess Auto 2026755 $39.99 6 $239.94Swing Arms Aluminum Bare Channel 6061 T6 OnlineMetals.com $49.08 1 $49.08Axle (Inches) 60" Keyed 3/4" diameter shaft McMaster-Carr 6117K19 $48.56 2 $97.12Hex Nut 5/8" (pkg 25) Ultra-Coated Grade 8 Steel Hex Nut 5/8"-18 Thread, 15/16" Width, 35/64" H93827A255 $14.10 1 $14.10Machining Maching of the above mentioned axles Tech Services $60.00 10 $600.00Shocks 5.33" travel 16.45" extended length eshocks.com BE5-A827-T6 $75.00 4 $300.00Square 80/20 (inches) Extruded Aluminum 1"X1" McMaster-Carr 47065T125/47065T123 $218.6180/20 Connectors Connectors for Extruded Aluminum 1"X1" McMaster-Carr 47065T163 $3.39 100 $339.00Bearings - Pillow 5/8" Base mount double sealed bearing McMaster-Carr 6494K11 $36.49 6 $218.94Bearings - Pillow 3/4" Base mount double sealed bearing McMaster-Carr 6664K22 $34.74 6 $208.44Bearings - Flange Mount Flange mount double sealed bearing McMaster-Carr 6736K22 $27.65 16 $442.40Al Sheet (Body) 32"X74" 1/16" thickness Metal Supermarkets $118.53 1 $118.53Al Sheet (Body) 26"X54" 1/16" thickness Metal Supermarkets $75.09 1 $75.09Hydraulic Fluid (Litres) Type F Automatic Transmission Fluid Wal-Mart $24.99 1 $24.99Hubs Steel Hub for 5/8" live axle mfgsupply 53-681 $19.99 6 $119.94

Total Cost $8,843.38

MATV Cost Estimate

Figure 13: MATV Cost Estimate

FINAL REPORT MATV


6 Project Deliverables

Final term deliverables for Project MATV include a final design package, virtual solid model, mechanical

stress analysis, and final report. In addition to these final deliverables, term deliverables included two

term progress reports, two class presentations, a final presentation, and a project website.

The final design package consists of the model design drawings outlined in this report, the component

selection details including specifications and supplier contact information, electronic calculations and

spreadsheet support for system sizing, the finite element analysis for mechanical performance of

fabricated parts, and the full system solid model as presented in the Solidworks design package.

It is anticipated that with the information outlined in this report and supporting documentation, a

functional prototype of the MATV could be pursued, or an alternate design iteration performed based

on our project specifications. We feel that Project MATV was given a good initial start this term, and

potential to expand the project exists for future interested parties.

All documentation not included in this paper is available on the project website.

http://www.engr.mun.ca/~jcole/

7 Recommendations and Conclusions

Now that Project MATV has completed its third design iteration, there are a number of

recommendations that would like to get passed on to a potential future project group. If not applicable

to future groups, these recommendations will serve as final conclusions surrounding this design

iteration.

To begin, we recommend that a closer look at the basic weight and size to performance specifications

undergo a review and optimization. Component availability has been a large issue within design for this

project. It seems that available hydraulic components are suitable for low performance with light

weight, or high power with a much larger weight.

FINAL REPORT MATV


The terrain specifications warrant a robust vehicle drive train and suspension for complex obstacle

navigation. This robust design causes the vehicle to increase in size and weight in order to provide

enough travel to conquer the obstacles.

As the vehicle increases in size and weight, the hydraulic system must perform at a higher level in order

to meet general performance specifications. Available component performance quickly runs out, and

more robust hydraulic and mechanical components must be selected. As higher performance

components are selected, weight increases, along with fuel consumption.

It seems that torque requirements warrant large output transmissions, which in turn require a large

torque engine with a large fuel consumption. These engines and transmissions are large weight

components, which drive up the torque requirements once more. Smaller components with smaller

diameter tires would lower the torque requirements,, but also result in lower top speeds.

It is recommended that weight and performance specifications increase in order to utilize the full

component specifications (as designed for example), or both weight and performance specifications

decrease in order to suit available lower performance components. With proper gearing, the current

design can utilize components to carry huge payloads, or alternatively output large speeds. Neither of

these are desirable for out current design specifications. Lower performance specifications, resulting in

a lower weight may also not be preferable.

Following initial prototype, a tubular frame and suspension members may warrant consideration for

final design. The current design utilizing 80/20 and aluminum suspension members is an effective

compromise between weight and convenience, however a tubular design may offer higher performance

characteristics for final design.

A review of tire design may be effective, to source an “Argo type” tire that propels the vehicle through

water more effectively. The current tire design was chosen out of availability and convenience, and

suits the general design performance specifications well, however may not be overly effective for water

propulsion.

Finally, the design and incorporation of a controls system for the MATV should be a large focus for the

next design iteration. Now that an initial platform and power train design is outlined, optimization of

design and incorporation of controls can be focussed on.

FINAL REPORT MATV

8936 Mechanical Project – MATV

Appendix I – Sauer-Danfoss BDU-21H

BD Series Hydrostatic Transmission

Technical Information

520L0935 · Rev AB · Jan 2009

BD Series Hydrostatic TransmissionTechnical InformationRevisions

2

© 2008 Sauer-Danfoss. All rights reserved.

Sauer-Danfoss accepts no responsibility for possible errors in catalogs, brochures and other printed material. Sauer-Danfoss reserves the right to alter its products without prior notice. This also applies to products already ordered provided that such alterations aren’t in conflict with agreed specifications. All trademarks in this material are properties of their respective owners. Sauer-Danfoss and the Sauer-Danfoss logotype are trademarks of the Sauer-Danfoss Group.

Table of RevisionsDate Page Changed Rev.

Jan 2009 35 Correction - Text AB

Jan 2006 - The first edition AA

HistoRy of Revisions

520L0935 · Rev AB · Jan 2009

BD Series Hydrostatic TransmissionTechnical InformationContents

3

geneRaL DesCRiPtion

teCHniCaLsPeCifiCations

oPeRatingPaRameteRs

system DesignPaRameteRs

featuRes anD oPtions

BD Series Transmission ................................................................................................................................. 5Design , BDU-10S ............................................................................................................................................ 6Design , BDU-21L ............................................................................................................................................ 7Pictorial circuit diagram, BDU-06/10S ..................................................................................................... 8System schematic, BDU-06/10S ................................................................................................................. 8Pictorial circuit diagram, BDU-10L/21L/21H ......................................................................................... 9System schematic, BDU-10L/21L/21H, BDP-10L .................................................................................. 9

Features and options ..................................................................................................................................10Operating parameters ................................................................................................................................11Fluid specifications ......................................................................................................................................11Efficiency , BDU-06S, 10S ............................................................................................................................12Efficiency , BDU-10L/21L, 21H, BDP-10L ...............................................................................................13

Overview .........................................................................................................................................................14Input speed ....................................................................................................................................................14System pressure ............................................................................................................................................14Charge pressure ............................................................................................................................................15Charge inlet pressure ..................................................................................................................................15Case pressure .................................................................................................................................................15Hydraulic Fluid...............................................................................................................................................15Temperature and Viscosity ........................................................................................................................16

Fluid and filtration ........................................................................................................................................17Reservoir ..........................................................................................................................................................17Control shaft force .......................................................................................................................................17Independent braking system ...................................................................................................................17Shaft load ........................................................................................................................................................18

Shaft options ..................................................................................................................................................19Bypass valve ...................................................................................................................................................21High pressure relief valve (HPRV) and Charge check (Overpressure protection) .................21Charge check valve with orifice ..............................................................................................................22Optional integral reservoir ........................................................................................................................24Filter ..................................................................................................................................................................24Fan .....................................................................................................................................................................24

520L0935 · Rev AB · Jan 2009

BD Series Hydrostatic TransmissionTechnical InformationContents

4

ComPonent seLeCtion

moDeLCoDe

ReCommenDeDinstaLLation &maintenanCe

instaLLationDRaWings

Maximum system pressure .......................................................................................................................25 Input power ....................................................................................................................................................26 Unit life .............................................................................................................................................................27

BDU master model code ............................................................................................................................29 BDP master model code ............................................................................................................................31

Housing installation ....................................................................................................................................32 Shaft installation ...........................................................................................................................................32 Start up procedure .......................................................................................................................................32Operation ........................................................................................................................................................32Maintenance ..................................................................................................................................................32

BDU-06S ...........................................................................................................................................................33 BDU-10S ...........................................................................................................................................................35BDU-10L ...........................................................................................................................................................35BDU-21L ...........................................................................................................................................................39BDU-21H ..........................................................................................................................................................39BDP-10L ...........................................................................................................................................................43Optional fan....................................................................................................................................................43

520L0935 · Rev AB · Jan 2009

BD Series Hydrostatic TransmissionTechnical InformationGeneral Information

5

the BD hydrostatic transmission can be applied for the transfer and control of power. It provides an infinitely variable speed range between zero and maximum in both forward and reverse modes of operation.the BDu transmission is a “ Z” style transmission with a variable displacement pump and a fixed displacement motor. The variable displacement pump features a cradle swashplate with a direct proportional displacement control. Reversing the direction of tilt of the swashplate reverses the flow of oil from the pump and thus reverses the direction of the motor output rotation. The fixed displacement motor uses a fixed swashplate. The pump and motor are of the axial piston design and utilize spherical-nosed pistons which are held against a thrust bearing by internal compression springs. The fluid supply for the BDu-10L/21L/21H transmission is contained in an external reservoir and passes through an external filter prior to entering the transmission and feeding the fixed displacement gerotor charge pump. Excess fluid in the charge circuit is discharged over the charge relief valve back to the charge pump inlet. Constant flow across a small fixed orifice connecting the charge circuit to the transmission housing supplements the cooling flow.the BDu-06s/10s transmission has a self-contained fluid supply and an integral filter. The fluid is forced through the filter by positive “head” on the fluid in the housing reservoir with an assist by the negative pressure created in the pump pistons as they create a vacuum. Charge check valves in the center section are used to control the makeup flow of fluid to the low pressure side of the loop. A spool type bypass valve is utilized in the transmission to permit moving the vehicle over short distances at low speeds without starting the engine.the BDP-10L is a variable displacement pump to utilize the pump kit of the BDu-10L transmission and designed for vehicle application which is for propel or for auxiliary functions where the system pressure requirements and design life can be met within pump rating.

• Acompletetransmissionfamilytomeettheneedsofsmallvehicleapplication.• 3Transmissionframesizes:6,10,21• PTOCapabilityon“Z”StyleTransmission• VariablePumpVersionof10FrameSizeAvailable(10cm3)• CostEffective,Compact,LightweightDesign• Lownoise• HighEfficiency• WorldwideSalesandService

BD seRies famiLy

520L0935 · Rev AB · Jan 2009

BD Series Hydrostatic TransmissionTechnical InformationGeneral description

6

Design BDU SERIES TRANSMISSION cross-section

BDU-10S

Tank

Built-in filter

Center section

Output shaft

Spring

Spool typebypass valve

Spring

Piston

Cylinder block

Thrust bearing

Housing

Shaft Seal

Input shaft

Ball bearing

Cooling fan

Cradle swash plate

520L0935 · Rev AB · Jan 2009


7

Design BDU SERIES TRANSMISSION cross-section

BDU-21L

Workingloop

Output shaft

Suctioncircuit

Charge check valve Spool type

bypass valve

Center section

Charge pump

Charge relief

Charge circuit

Suction port SpringPiston

Input shaft

Ball bearing

Shaft Seal

Housing

Thrust bearing

Cylinder block

Workingloop

Cradle swash plate

(continued)

520L0935 · Rev AB · Jan 20098


PiCtoRiaL CiRCuitDiagRam

BDU-06S, BDU-10S

system sCHematiC

BYPASSVALVE

CYLINDERBLOCKASSEMBLY

INPUTSHAFT

VARIABLESWASHPLATE VARIABLE

DISPLACEMENTPUMP

BDUHOUSING

RESERVOIR

BUILT-INFILTER(BDU-10S)

CHECK VALVE

CHECK VALVECYLINDER BLOCKASSEMBLY

OUTPUTSHAFT

DISPLACEMENTMOTOR

FIXEDSWASHPLATE

CONTROL SHAFT “b”

CONTROL SHAFT “a”

HYDRAULIC CIRCUIT

ø0.7 ø0.8

ø0.7 ø0.8

CHECKVALVEWITHø0.7 ORIFICEOPTIONCODE:07

BALL CHECK VALVE

OPTIONCODE:BB



BALL CHECK VALVE

OPTIONCODE:BB


Workingloop(high pressure)

Workingloop(low pressure) Suction line Case drain fluid

FIXED

520L0935 · Rev AB · Jan 2009

20.6MPa 17.2MPa 13.7MPa 20.6MPa 20.6MPa

20.6MPa 17.2MPa 13.7MPa 20.6MPa 20.6MPa

9


PiCtoRiaL CiRCuitDiagRam

BDU-10L, BDU-21L, BDU-21HBDP-10L (part of pump)

system sCHematiC

BYPASSVALVE

CYLINDERBLOCKASSEMBLY

INPUTSHAFT

VARIABLESWASHPLATE

VARIABLEDISPLACEMENTPUMP

RESERVOIR

FILTER

CHECK VALVE

CHECK VALVE CYLINDER BLOCKASSEMBLY OUTPUT

SHAFT

FIXEDSWASHPLATECOOLING

ORIFICE

CHARGEPUMP

CHARGERELIEFVALVE

SUCTIONPORT

DRAIN PORTHYDRAULIC CIRCUIT



BALL CHECK VALVEOPTIONCODE:BB



ø1.0 ø1.2

CHECKVALVEWITHRELIEF VALVE ANDø0.85 ORIFICEOPTIONCODE:RB

CHECKVALVEWITHRELIEF VALVE ANDø0.7TWINORIFICEOPTIONCODE:RA

CHECKVALVEWITHRELIEF VALVE

OPTIONCODE:R2


OPTIONCODE:R1


OPTIONCODE:R0

ø0.85

ø0.85ø0.7×2

21L

21H

ø0.8

ø0.7×2

BDP-10L

Workingloop(high pressure)

Workingloop(low pressure)

Suction line Case drain fluid

SUCTIONPORT

DRAIN PORTHYDRAULIC CIRCUIT



ø0.8

CHECKVALVEWITHRELIEF VALVE ANDø0.85 ORIFICEOPTIONCODE:RB

CHECKVALVEWITHRELIEF VALVE ANDø0.7TWINORIFICEOPTIONCODE:RA


OPTIONCODE:R2


OPTIONCODE:R1


OPTIONCODE:R0

BALL CHECK VALVEOPTIONCODE:BB



ø1.0 ø1.2

(continued)

DISPLACEMENTMOTOR

FIXED

520L0935 · Rev AB · Jan 200910

BD Series Hydrostatic TransmissionTechnical InformationTechnical specifications

featuRes anD oPtions

features unitProduct type & frame

BDu-06s BDu-10s BDu-10L BDu-21L BDu-21H BDP-10L

Pump

Displacementcm³

[in³]

6

[0.37]

10

[0.61]

10

[0.61]

21

[1.28]

21

[1.28]

10

[0.61]

Swashplate Angle degree 15 15 15 15 15 15

Control Shaft degree 15 21 21 22 22 21

MotorDisplacement

cm³

[in³]

6

[0.37]

10

[0.61]

10

[0.61]

21

[1.28]

21

[1.28]—

Swashplate Angle degree 15 15 15 15 15 —

Charge Pump Displacement cm³ [in³] N.A. N.A. 1.9 [0.12] 2.1 [0.13] 3.0 [0.18] 1.9 [0.12]

Output Speed

Ratedmini-1

3000 3000 3600 3600 3600 3600

Maximum (intermittent) 3200 3200 3800 3800 3800 3800

Maximum Output Torque (Theoretical)Nm

[lbf-in]

9.8

[87]

23.4

[208]

23.4

[208]

49.2

[436]

72.1

[639]—

Input Power (Maximum)kW

[ps]

1.1

[1.5]

2.2

[3.0]

3.7

[5.0]

7.4

[10.0]

11.0

[15.0]

3.7

[5.0]

Weightkgf

[lbs]

4

[9]

6.3

[14]

6.5

[14]

10

[22]

10

[22]

4.6

[10]

Control Torque Required

to Stroke Pump (Maximum)

Nm

[lbf-in]

8.8

[78]

19.6

[174]

19.6

[174]

22.5

[200]

24.5

[217]

19.6

[174]

Mounting See Installation Drawings

Rotation Clockwise or Counterclockwise

Suction / Oil Tank Port (SAE O-ring Boss) 7/8-14UNF 7/16-20UNF 9/16-18UNF 7/16-20UNF

Other ports See Installation Drawings

Shaft P34, 36 ~ 38, 40 ~ 42

Bypass Valve O.P. STD STD STD STD STD

Neutral Valve / Orifice N.A./N.A. N.A./O.P. N.A./O.P. O.P./O.P. O.P./O.P. N.A./O.P.

High Pressure Relief Valve N.A. N.A. N.A. N.A. STD N.A.

Filtration W/O built-in ExternalExternal

(Option, Integrated)External

Reservoir Integrated Integrated External External External

Space for the oil in the housing cm3 450 550 550 700 700 250

*SAE J1926-1 / ISO 11926-1

520L0935 · Rev AB · Jan 2009


11

fLuiD sPeCifiCations viscosity mm²/sec (cSt) [SUS]Minimum 7 [49]

Continous 12 [70] - 60 [278]

Maximum 1600 [7500]

oil temperature °C [°F]

Minimum −10 [14]

Maximum Continuous 82 [180]

Maximum Intermittent 104 [219]

oPeRating PaRameteRs

Parameter unitProduct type & frame

BDu-06s BDu-10s BDu-10L BDu-21L BDu-21H BDP-10L

Input Speed

Minimum

min-11000 600 600 600 600 600

Rated 3000 3000 3600 3600 3600 3600

Maximum 3200 3200 3800 3800 3800 3800

System Pressure

Ratedbar

[psi]

105

[1530]

150

[2185]

210

[3059]

150

[2185]

Maximum150

[2185]

175

[2549]

210

[3059]

245

[3569]

175

[2549]

Charge Pressure bar [psi] N.A. 3 [44] ~ 5 [73]

Charge Inlet Pressure bar [psi] N.A. 0.8 [12] abs

Case Pressure bar [psi] 0.3 [4]

Rated bar

[psi]

0.3 [4]

Maximum (Cold Start) 0.7 [10]

520L0935 · Rev AB · Jan 2009


BDU-06S

ηvηm

ηt

100

Effic

ien

cy

%

90

80

70

60

50

40

30

20

10

03 5 7

Theoretical Output Torpue Nm

40%

40%

50%

50%

55%

55%

60%

60%

65%

65%

70%

70%

45%

45%

10

5

0 1000 2000 3000

BDU-06S

Ou

tpu

t T

orq

ue

Nm

Output Speed min-1

BDU-10S

ηv ηmηt

100

90

80

70

60

50

40

30

20

10

05 9 11 13 17

Effic

ien

cy

%


40%

45%

50%

55%

60%

65%

70%

73%

73%

70%

65%

60%55%

50%45%40%

20

10

0 1000 2000 3000

BDU-10S

Ou

tpu

t T

orq

ue

Nm

Output Speed min-1

Inputspeed:3000min-1Oiltemperature:50°CFull Displacement


Inputspeed:3000min-1Oiltemperature:50°C


12

effiCienCy

Efficiency ( ηv:Volumetric,ηm:Mechanical,ηt:Overall)


520L0935 · Rev AB · Jan 2009


BDU-10L

ηv ηmηt

1009080

70

60

5040

30

20

10

05 5 7 9 11 13 15 16 18 20 22

Effic

ien

cy

%


40%

45%

50%

55%

60%

65%

70%

73%

73%

70%

65%

60%55%

50%45%40%

20

10

0 1000 2000 3000

BDU-10L

Ou

tpu

t T

orq

ue

Nm

Output Speed min-1

BDU-21L/21H

ηv ηmηt

10090

8070

605040

3020

100

11 23 34 46 57 65

Effic

ien

cy

%


40%

45%

50%

55%

60%

65%

70%

75%

70%

75%

65%

60%55%

50%45%40%

50

40

30

20

10

0 1000 2000 3000

BDU-21L/21H

Ou

tpu

t T

orq

ue

Nm

Output Speed min-1

BDP-10L BDP-10L

35.0

30.0

25.0

20.0

15.0

10.0

5.0

0.0

Ou

tpu

t flo

w

Lite

r / m

in

at no road

at 105 bar

70 bar

105 bar

1500 1000500 2000 2500 3000

Input Speed min-11500 1000500 2000 2500 3000

Input Speed min-1

100

9080706050403020

100

Effic

ien

cy

%




BDP-10L BDP-10L

35.0

30.0

25.0

20.0

15.0

10.0

5.0

0.0

Ou

tpu

t flo

w

Lite

r / m

in

at no road

at 105 bar

70 bar

105 bar

1500 1000500 2000 2500 3000

Input Speed min-11500 1000500 2000 2500 3000

Input Speed min-1

100

9080706050403020

100

Effic

ien

cy

%

Oiltemperature:50°C

(continued)


13

effiCienCy


Overall EfficiecyOutput flow - Input Speed


Oiltemperature:50°CFull Displacement

520L0935 · Rev AB · Jan 2009

BD Series Hydrostatic TransmissionTechnical InformationOperating Parameters

14

oveRvieW Maintain operating parameters within prescribed limits during all operating conditions.This section defines operating limits given in the table Operating parameters, page 11.

minimum speed is the lowest input speed recommended during engine idle condition.Operating below minimum speed limits pump’s ability to maintain adequate flow for lubrication and power transmission.Rated speed is the highest input speed recommended at full power condition.Operating at or below this speed should yield satisfactory product life.maximum speed is the highest operating speed permitted. Exceeding maximum speed reduces product life and can cause loss of hydraulic power and braking capacity. Never exceed maximum speed limit under any operating conditions.

Warningunintended vehicle or machine movement hazard.Exceeding maximum speed may cause a loss of hydrostatic drive line power and braking capacity. You must provide a braking system, redundant to the hydrostatic transmission, sufficient to stop and hold the vehicle or machine in the event of hydrostatic drive power loss.

system pressure is the differential pressure between system ports A and B. It is the dominant operating variable affecting hydraulic unit life. High system pressure, which results from high load, reduces expected life. Hydraulic unit life depends on the speed and normal operating, or weighted average, pressure that can only be determined from a duty cycle analysis.applied pressure is the chosen application pressure found within the order code for the transmission unit. This is the pressure at which the driveline generates the maximum pull or torque in the application.Rated pressure is the design pressure from the transmission unit. Applications with applied pressures at or below this pressure should yield satisfactory unit life given proper component selection guidelines.maximum pressure (Peak) is the highest intermittent pressure allowed under any ircumstances. Applications with applied pressures between rated and peak should be attempted only with application, duty cycles and life expectation analyses. This requires factory approval.

All pressure limits are differential pressures referenced to low loop (charge) pressure.Subtract low loop pressure from gauge readings to compute the differential.

inPut sPeeD

system PRessuRe

520L0935 · Rev AB · Jan 2009


15

CHaRge PRessuRe The charge pressure setting listed in the technical specifications is based on the chargeflow across the charge pressure relief valve at fluid temperature at 50˚C [120˚F].

Charge pump inlet conditions must be controlled in order to achieve expected life and performance. A continuous inlet vacuum of no less than 0.8 abs bar is recommended. Normal vacuums less than 0.7 abs bar would indicate inadequate inlet design or stricted filter.

Under normal operating conditions, the maximum continuous case pressure must not exceed 0.3 bar (4PSI). Maximum allowable intermittent case pressure during cold start must not exceed 0.7 bar (10PSI).

CautionPossible component damage of leakage.Operation with case pressure in excess of these limits may damage seals, gaskets, and/or housings, causing external leakage. Performance may also be affected since charge and system pressure are additive to case pressure.

Ratings and performance data are based on operating with hydraulic fluids containing oxidation, rust and foam inhibitors. These fluids must possess good thermal and hydrolytic stability to prevent wear, erosion, and corrosion of pump motor components. Never mix hydraulic fluids of different types. Thefollowingfluidsaresuitable:• EngineoilsAPIClassificationSL,SJ(forgasolineengines)andCI-4,CH-4,CG-4, CF-4, CF and CD (for diesel engines) • HydraulicOilISO11158-HM(Sealcompatibilityandvanepumpwearresistanceper DIN51524-2 must be met)• HydraulicOilISO11158-HV(Sealcompatibilityandvanepumpwearresistanceper DIN51524-3 must be met)• HydraulicOilDIN51524-2HLP• HydraulicOilDIN51524-3HVLP

CHaRge inLet PRessuRe

Case PRessuRe

HyDRauLiC fLuiDs

520L0935 · Rev AB · Jan 2009


16

Temperature and viscosity requirements must be concurrently satisfied. The data shown in the table, Fluid Specifications, page 11, assume petroleum-based fluids are used.

The high temperature limits apply at the hottest point in the transmission, which is normally the case drain. The system should generally be run at or below the rated temperature. The maximum temperature is based on material properties and should never be exceeded.

Cold oil will generally not affect the durability of the transmission components, but it may affect the ability of oil to flow and transmit power; therefore temperatures should remain over 16˚C [30˚F] above the pour point of the hydraulic fluid. The minimum temperature relates to the physical properties of component materials.

For maximum unit efficiency and bearing life the fluid viscosity should remain in the recommended operating range. The minimum viscosity should be accepted only during brief occasions of maximum ambient temperature and severe duty cycle operation. The maximum viscosity should be permitted only at cold start.

Heat exchangers should be sized to keep the fluid within these limits. Testing is recommended to verify that these temperature limits are not exceeded.

temPeRatuRe anDvisCosity

520L0935 · Rev AB · Jan 2009

BD Series Hydrostatic TransmissionTechnical InformationSystem design parameters

17

fLuiD anD fiLtRation To prevent premature wear, it is imperative that only clean fluid enters the hydrostatic transmission circuit. Therefore an inlet filter better than β20=1.4 is required in the charge pump inlet line. This filter should not have a bypass and should be changed regularly to ensure system reliability. The BD series hydrostatic transmission requires system filtration capable of maintaining fluid cleanliness at ISO 4406-1999 class 22/18/15 or better.

The BDU-06S and BDU-10S are designed with optional integrated reservoir. A reservoir for BDU-10L and BDP-10L larger than the 2 liter tank size is recommended. A reservoir for BDU-21L/H larger than the 5 liter tank size is recommended. The hoses or piping size is recommended to be larger than 3/8 inch normal tube OD.

The BDU transmission is designed with direct displacement control (DDC). DDC can be located at either side of the housing. It provides a simple, positive method of control.Movement of the control shaft causes a proportional swashplate movement, thus varying the pump’s displacement from full displacement in one direction to full displacement in the opposite direction.The approximate maximum control torque necessary to rotate the control shaft is shown in the table of technical specifications. A stopper to prevent over-stroke is required at the end of maximum angle of control shaft. The control shaft force should be kept at or below the force in the table below.

features unitProduct type & frame

BDu-06s BDu-10s BDu-21L

Allowable maximum force

for control shaftNm 10 20 25

Vehicle propel applications may require a provision for non-linear control input to reduce control sensitivity near neutral. Damping or frictional forces may be necessary to produce the desired control feeling.These units do not include any neutral centering device for the swashplate. It is necessary to provide a force in the machine’s control system that will hold the swashplate at the desired angle. A “ fail safe “ which will return the swashplate to the neutral in the event of linkage failure is recommended.

Warningunintended vehicle or machine movement hazard.The loss of hydrostatic drive line power, in any mode of operation (forward, neutral, or reverse) may cause the system to lose hydrostatic braking capacity. You must provide a braking system, redundant to the hydrostatic transmission, sufficient to stop and hold the vehicle or machine in the event of hydrostatic drive power loss.

ReseRvoiR

ContRoL sHaft foRCe

inDePenDent BRakingsystem

520L0935 · Rev AB · Jan 2009

BD Series Hydrostatic TransmissionTechnical InformationFeatures and options

0 10

200

400

600BDU-06S

BDU-10S/10L,BDP-10L

BDU-21L/21H

200

400

600

800

200

400

600

800

1000

1200

1400

20 30

0 10 20 30 40 50

0 10-10 20 30 40 50

18

sHaft LoaD The maximum allowable radial road of input shaft (Re) is based on the maximum external moment and the distance from the housing surface to the input shaft. Thelimitofradialloadofinputshaftisshownthefigurebelow:

The maximum shaft thrust in (tin) of input shaft is 18% of allowable radial road (Re) of the input shaft. The shaft thrust out (tout) of the input shaft should be no load. The radial and thrust load of the output shaft should be no load.

No Load

No Load

No Load

Tout (No Load)

Re:seefigures

Tin

distance (L)

distance (L) mm →

distance (L) mm →

distance (L) mm →

Re Re

N →

Re

N →

Re

N →

520L0935 · Rev AB · Jan 2009


This charge pump housing isapplied only for BDU-10L.

d D

D

D

19

sHaft oPtions The BDU transmissions are available with a variety of straight key, JIS Spline, JIS Serra-tion, SAE Spline shaft for input shaft, PTO shaft and output shaft. Details are shown in the Installation Drawings, page 33 through page 43.

PTO Shaft

Output Shaft

Output

Shaft

Options

JIS Spline

15×13×1.0

Code:S16

(BDU-06S)

(BDU-10S)

(BDU-10L)

JIS Spline

20×18×1.0

Code:K18

(BDU-10S)

(BDU-10L)

SAE Spline

32/64-16T

Input Shaft

PTO Shaft

Options

Input Shaft

Options

PTO

None

Straight-Keyed D=15mm

Code:KA0(BDU-06S)

KB0 (BDU-10S)

KB1 (BDU-10L)

Straight-Keyed D=15mmStraight d=12.7mm

Code:PB2(BDU-10S)

Code:PB4(BDU-10L)


JIS

Serration

12×23×0.5

Code:J13

(BDU-06S)

(BDU-10S)

(BDU-10L)

Code:PB1(BDU-10S)

Code:PB3(BDU-10L)

BDU-06S

BDU-10S

BDU-10L

520L0935 · Rev AB · Jan 2009


D

D

D

20

sHaft oPtionsContinueD

JIS Spline

20×14×1.25

Code:S22

(BDU-21L)

(BDU-21H)

JIS Spline

20×18×1.0

Code:J18

(BDU-21L)

(BDU-21H)

SAE Spline

32/64-22T

Code:KC1(BDU-21L)

KC2 (BDU-21H)

Code:J14

(BDU-21L)

(BDU-21H)

BDU-21L

BDU-21H

JIS Spline

15×13×1.0

SAE Spline

32/64-16T


Code:PC1(BDU-21L)

PC2(BDU-21H)


Code:PC5(BDU-21L)

PC6 (BDU-21H)

PTO Shaft

Output Shaft

Output

Shaft

Options

Input Shaft

PTO Shaft

Options

Input Shaft

Options

PTO

None


520L0935 · Rev AB · Jan 2009


21

ByPass vaLve In some applications, it is desirable to move the vehicle over short distances at low speed without starting the engine. A bypass valve allows oil to be routed from one side of the pump/motor circuit to the other, thus allowing the motor to turn. The bypass valve must be fully closed during normal vehicle operation.BDU series transmissions utilize a spool-type bypass valve. The bypass valve plunger must be depressed manually to open the valve. This connects both sides of the main hydraulic circuit to the housing case and allows fluid to circulate without rotating the pump, prime mover and motor. A spring closes this valve on the 6S, 10L and 10S transmissions, while charge pressure closes the valve on the 21L and 21H transmissions. The BDP-10L pump utilizes a screw-type bypass valve.

The BDU-21H transmission is available with a combination charge check and high pressure relief valve assembly. High pressure relief valves are available in a range of settings as shown in the Model Code, page29, 30 and 31. Individual port pressure set-tings may be specified. The high pressure relief valve settings are a differential pressure (referenced to charge pressure).

HigH PRessuReReLief vaLve (HPRv)anD CHaRge CHeCk

( oveR PRessuRe) PRoteCtion

Check and Relief valve for BDu-21H

option codePressure setting orifice

bar [psi]

R0 210 -

R1 175 -

R2 140 -

RA 210 0.7 Twin

RB 210 0.85

Charge circuit

Check and Relief valve

Bypass valve

Workingloop(Main hydraulic circuit)

Check and Relief valve

BDU-21H Center section

Workingloop(Main hydraulic circuit)

520L0935 · Rev AB · Jan 2009


22

The BDU transmissions are equipped with charge check valves. In some applications, it is desirable to use charge check valve with orifice for expanding null dead band, giving both the safety measure to prevent the vehicle movement in the neutral position of the control shaft and easy adjustment of neutral position when connected to vehicle linkage. The orifice connects the working loop, which is a main hydraulic circuit, to a charge circuit. It always allows some internal leakage to ensure the expanding null dead band around neutral position of control shaft. However, it decreases the volumetric efficiency, particularly at high system pressure in the working loop. It is recommended to install the orifice in a specific working loop, which is pressurized when the vehicle moves in reverse. The orifice diameter improves the null dead band but decreases the volumetric efficiency. A cross section and characteristics are shown below. The charge check valves with orifice are available in a range of orifice diameters as shown in the Model Code, page 29, 30 and 31.

CHaRge CHeCk vaLve WitH oRifiCe

Inputspeed:3000min-1OilTemp:50˚CNo load

Features UnitBDU-10S/10L/21L/21H

WithoutOrifice

Deadband of

Control Shaft Angle

(DB-STD)

[degree] Approx. 0.1

Features Unit

BDU-10S/10L BDU-21L BDU-21LH

Orifice diameter [mm]

φ0.7 φ0.8 φ1.0 φ1.2 φ0.85 φ0.7 twin

Deadband of

Control Shaft Angle

(DB-OR)

[degree]Approx.

0.5

Approx.

0.7

Approx.

0.5

Approx.

0.7

Approx.

0.35

Approx.

0.5

with Orifice

Reverse

DB-OR

Neutral-OR Neutral-STD

DB-STD

Control Shaft Angle

Forward

Output Flow

520L0935 · Rev AB · Jan 2009


BDU-10S/10L

BDU-21L

BDU-21H

23

CHaRge CHeCk WitH oRifiCe

Check Valve (Ball) without orifice

Check Valve with orifice

Check & Relief without orifice

Check & Relief with orifice

BDU-10L Check Valve BDU-10S Check Valve

orifice

orifice

Check Valve (Ball) without orifice

Check Valve with orifice

orifice

520L0935 · Rev AB · Jan 20

Documents

DWYER APRIL 9, 2010jcole/FRep.pdfsmall all‐terrain vehicle, capable of navigating rough terrain and water obstacles, typical of a rural NL location. Basic vehicle specifications