Preliminary Project Plan P0820 2/5/6/7/8 – RP1 Motor Module

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Preliminary Project PlanP08202/5/6/7/8 – RP1 Motor Module

Emilien Barrault (ME) Wendy Fung (ME)

Jason Kenyon (ME)Jasen Lomnick (ME)

Hoainam Nguyen (ME)

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Project Plan• Project Name

– RP1 Motor Module • Project Number

– P08202/5/6/7/8 • Project Family

– Robotic Platform Family• Track

– Vehicle Systems Technology• Start Term

– 2007-2 planned academic quarter for MSD1• End Term

– 2007-3 planned academic quarter for MSD2• Faculty Guide

– Dr. Wayne Walter (ME)• Faculty Consultant

– Dr. Dan Phillips (EE)• Faculty Consultant

– Dr. Hoople (TBD)• Primary Customer

– Dr. Edward Hensel (ME)

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Mission StatementProduct Description

A fully functional, open source, open architecture, scalable motor module subsystem for use on the 1 kg (RP1) robotic vehicular platform. Each motor module will have the ability to drive, steer, communicate with a controller, and work cooperatively with a number of motor modules in a number of configurations to drive a robotic vehicular platform capable of carrying a 1kg payload.

Key Business GoalsTo provide an open source, open architecture designTo provide an off-the-shelf motor module for the mobility of a 1 kg robot platformTo provide a motor module that is scalable according to payload requirementsTo publish the RP1design to be used by anybody wishing to mobilize a 1kg payload. The team must provide complete documentation of the analysis, design, manufacturing, fabrication, test, and evaluation of this subsystem to a level of detail that a subsequent team can build upon their work with no more than one week of background research

Primary Market Dr. Edward HenselRP1 Platform teamFuture SD teams

Secondary Market FIRST RoboticsFaculty projectsClass-based projects

Stakeholders Dr. Edward HenselFaculty members1 kg platform teamGleason Foundation RITBrinkman Machine ShopFIRST Robotics

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Robotic Platform Family Overview

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Benchmarking (100kg Motor Module)

• RP100 Motor ModuleProduct Teardown– Make use of quick disconnect wiring connectors

• All wiring between platform and module and all module subsystems• Avoid the need for unscrewing wiring, which will add to ease of assembly

– Wing nuts are good for quick assembly/disconnect– To remove EMF cage must disconnect every electrical component before the cage

can be removed. • There are several areas on the module that can not be reached without an

extreme amount of disassembly– No fall resistance– Too much slop in the turntable assembly– Meshing of gears (mainly the internal ring\spur) – Accessing internal gears– No warning labels– Imperfect welds

Running RP100 Video

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P07202: RP100 Motor Module

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Benchmarking (10 kg Motor Module)Appeal • Looks impressive with lightweight and transparent lexan sides • Shiny steel and aluminum • Exposed circuitry • Exposed drive system • Exposed "guts" lets users know how it works and is easy to diagnose problems • Use of bushings instead of bearings gives it a cheap and inaccurate feeling • Looks clunky • Could be a much more compact design • Size of turntable obviously determined overall design

Operating Characteristics • Large and awkward to handle • Drive wheel is easy to spin but lots of slop in drive system • I cannot readily tell how to use the product: Where do I plug it in? What

orientation do I mount it in?

Product Teardown

1) Functions • Must drive wheel • Must turn wheel • Must be able to be addressed and controlled by platform • Must physically attach to platform • Must be electrically plugged into platform

2) Technology - Product employs: • Bevel Gears • Synchronous belt drive • Incremental encoders for drive and steering motors (US Digital P/N E5S-400-

250-IH) • 1 24VDC Drive Motor w/integrated gearbox (Shayang Ye Industrial Co. P/N

IG420017-C520) • 1 24VDC Steering Motor w/integrated gearbox (Shayang Ye Industrial Co. P/N

IG320071-41F01) • Various electrical and control circuitry • Large turntable • Colson Hi-Tech Performa 5 x 1.5 Drive and Steering wheel

3)Strengths and Weaknesses

• Large, clunky, homemade looking

• Very big, definitely not 1/10 the size of the RP100 motor module

• Visibility of "guts" is attractive and easy to diagnose problems

• Incremental encoders cannot tell control system "where things are"

• Had to extend motor shafts

4) Materials used

• PCB's

• Wires

• 2 DC Motors

• Encoders for Motors (Qty 2)

• Turntable

• Bevel gear pair

• Synchronous belt drive (rubber belt, plastic drive pulley, metal driven pulley)

• Shaft couplings to extend shafts

• Less than 1 ft^2 of 1/8" aluminum

• About 5 ft^2 of 1/4" lexan

• Miscellaneous fasteners

• Zip-ties

• E-clips for retaining shafts

• Bronze Bushings (Qty 6)

• Internal gear pair

• Steel driveshafts

5) Manufacturing

• Cutting lexan, aluminum, and driveshafts

• Drilling lexan, aluminum, turntable, internal gear pair

• Machining E-clip grooves in driveshafts

• Pressing bushings into lexan

• Fastening all peices together

• Wiring components, holding wires with zip-ties

• Experience and Knowledge

• Design does not seem rugged, very fragile

• Design seems imprecise

• If you wanted to replace a broken part you would have to disconnect quite a bit to get to the part (eg. wheel, encoder, gear pair, shaft extension couplings, motor mounting screws, etc.)

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Benchmarking (100 kg Platform)• Appeal

– Simple– Big enough for 100kg– No special colors– Not aesthetic

• Operating Characteristic– User Friendliness

• Simple to understand• Not easy to move the robot

• Operating characteristic

• Product teardown– Dissection and Analysis

• Functions– safely

» Do not hurt people» Electrical wire must be well

arranged– Carry object

» Must contains a variety forms of object

» Carry 100kg• Easy to use and

maintenance– Easy to assembly– Easy to change the component– Documentation must be as clear as possible

• Technology– Open architecture– Cog-wheel bond with plastic chain– Ball contact for the direction– platform with tie rod structure

• Strengths and Weakness– Strengths

• simple• Open architecture• Cheap material• Easy to assembly

– Weakness• There is too much cables and wire

• Materials used– Plastic

• Wheel• Power source box• Wire skin

– Aluminum• Platform• Cog-wheel

– Steel• Manufacturing

– Bar: cut– Assembly: by screw– Motor-Module peaces: Manufactured by machines

Pictures

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Benchmarking (10 kg Platform)• Appeal

– A lot of place to carry 10 Kg,– Size of motor module has an impact on the size of

platform,– No protection for component,– Not very beautiful

• Operating characteristics– It is possible to do a mistake when we assembly motor

module,– It is essay to carry 10 kg can payload a lot of different

object (form),– Platform is very big,

Product teardownDissection and analysis

– Function• Have one platform to carry 10Kg,• Bumper to dampen impact,• Some place to receive batteries, motors

modules, and other component for the command,

• Must be electrically plugged with motor module,• Must receive different motor module,

– Technology• The platform is an assembly about plastic

pieces,

• Strengths and weaknesses– Strengths:

• Structure is very simple,• Separation between payload carry and component,• Structure is created in truss structure (it is more

rigid),– Weaknesses:

• Structure is no very strong,• Structure could be more compact,

• Materials– Plastic,– Steel square,– Rubber bumper,– Screw,

• Manufacturing– All the platform is make by simple part, like square rob,

square plate,– The structure is assembled with cap screw,

Experience and knowledge• How things work

– Each motor module is assembly by the side and is lock by screw,

– There are two floors one for carry the payload and one for carry different component,

– Floor to carry the payload is in plastic,– Floor to carry different components is an assembly of

plastics parts,– This two floors are link by truss structure,

• Articulate your own past experiences and uses with platform– The truss structure is very strong and that it is a good point

but requires more precision during the construction than another.Pictures

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Staffing Requirements and Multiple Team Structure

Our mission:

How can we get teams to make a motor module that will be better through collaboration and getting the most out of their available resources (other teams, research, faculty expertise) as opposed to an individual team making one motor module or 5 different teams working independently?

We will need to carefully structure the project teams individual focuses to efficiently use student skills and their collaboration.

Structure Possibilities:

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Communications Explanation

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Student Responsibilities based on Multiple Team Structure

Option 1: Setup for all 5 teams: Every team has the same mission statement and we have the possibility for 5 totally different directions. Teams can collaborate as little or as much as they wish.

2 ME Students: - Design and build the drive system including drive and steering to the wheel

- Choose mechanical components based on stress and fatigue analysis- CAD work- Machining and assembly- Design to work within mechanical platform interface

2 EE Students: - Choose PWM Motor controller for use on MM- Choose and implement feedback system (encoders and sensors)- PCB Design based on controls criteria- Characterize electrical platform interface and wiring

2 CE Students: - Choose or develop microcontroller to receive commands and transmit PWM signals to motor controller

- Develop control algorithm to make MM individually addressable and talk with central command receiver

- Work with feedback from encoders and sensors

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Continued….Option 2: Every team will have a segment of the design they will be responsible for.

They will have to work with the other teams on the interface between segments.

Team1 (Design Drive system) : 5 ME Students: - Design and build the drivetrain to drive the wheel - CAD work

- Machining and assembly - Design to work within mechanical platform interface 1 IE Student: - Manage interface between drive system and electrical and control system

Team 2 (Design Steering System): 5 ME Students: - Design and build the steering system to drive wheel - CAD work - Machining and assembly

1 IE Student: - Manage interface between drive system and electrical and control system Team 3 ( Design Controls System): 5 EE Students: - Choose and implement PWM Motor controller

- PCB layout, wiring - Encoder and sensors implementation into controls

1 ME Student: - Implement encoder and sensors, manage interface between encoder, sensors, drive and steering system

Team 4 ( Design Control and Architecture Program) : 4 CE Students: - Choose or develop microcontroller to receive commands and transmit

PWM signals to motor controller - Develop control algorithm to make MM individually addressable and

talk with central command receiver - Work with feedback from encoders and sensors

2 EE Students: - Choose PWM Motor controller for use on MM - Choose and implement feedback system (encoders and sensors) - PCB Design based on controls criteria

- Characterize electrical platform interface and wiring Team 5 ( Manage all Design Interfaces): 3 ME Students: - Manage the interfaces between: Drive and Steering Systems

Motor Module and Platform (mechanical) Drive and steering systems and their

encoders and sensors 2 EE Students: - Manage the interfaces between: Encoders, sensors, and

microcontroller Motor Module and Platform (electrical)

1 CE Student: - Manage the interfaces between: Microcontroller and sensors and encoders

Motor Module and Platform (controls)

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Continued….Option 3: All teams will build the entire motor module but will have a specific focus.

Team1 (Use CAN Communication) : 2 CE Students: - Develop CAN control algorithm to make MM individually addressable and talk with central command receiver - Work with feedback from encoders and sensors


- Characterize electrical platform interface and wiring 2 ME Students: - Work collaboratively with Teams 3 and 5 to develop steering and drive

systems Team 2 (Use SPI Communication) : 2 CE Students: - Develop SPI control algorithm to make MM individually addressable and

talk with central command receiver - Work with feedback from encoders and sensors



systems Team 3 ( Optimize Steering System): 4 ME Students: - Design and build the steering system to drive wheel

- CAD work - Machining and assembly

1 EE Student: - Choose and implement feedback control for encoders and/or sensors 1 IE Student: - Manage interface between drive system and electrical and control system

Team 4 ( Use I^2C Communication) : 2 CE Students: - Develop I^2C control algorithm to make MM individually addressable and talk with central command receiver - Work with feedback from encoders and sensors



systems Team 5 ( Optimize Drive System): 5 ME Students: - Design and build the drivetrain to drive the wheel

- CAD work - Machining and assembly - Design to work within mechanical platform interface 1 IE Student: - Manage interface between drive system and electrical and control system

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Pro’s and Con’s of each Multiple Team Structure Option

• Option 1: Pro’s:

– 5 chances for a great Motor Module

– Least constraining of design options

Con’s:

– Does not promote collaboration

– Not every motor module will work with a single platform


– Each individual segment of the design should be very well designed

– Promotes inter-team collaboration

Con’s:

– Will be very difficult to manage interfaces between all segments

– One team’s failure will mean there is no final motor module product


– Promotes inter-team collaboration

– Build’s on student’s specialties

Con’s:

– Will be difficult to manage interfaces between all segments

Notes:

To choose our Multiple Team Structure, we will eventually be using a Pugh Diagram ( a rating tool for justification and choosing from different options)

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Preliminary Work Breakdown Structure

Person Week 0->1 Tasks (8 Dec 06)

Week 1->2 Tasks (15 Dec 06)

Week 2->3 Tasks (22 Dec 06)

ME Student 1 Understand overall robot/past designs Understand setup of gears and wheels Look at current project site Understand team structures, roles,

responsibilities

Understand constraints, expec tations, and requiremen ts

Understand needs and specifications Adjust needs and specifications

Brainstorming design ideas Make preliminary BOM Build test fixture

ME Student 2 Understand overall robot/past designs Understand interfacing and everything else Look at current project site Understand team structures, roles,

responsibilities




ISE Student 1 Understand overall robot/past designs Understand integration of the systems Look at current project site Understand team structures, roles,

responsibilities




EE Student 1 Understand overall robot/past designs Understand the power system Look at current project site Understand team structures, roles,

responsibilities




EE Student 2 Understand overall robot/past designs Understand the communications system Look at current project site Understand team structures, roles,

responsibilities




EE Student 3 Understand overall robot/past designs Understand controller system Look at current project site Understand team structures, roles,

responsibilities




CE Student 1 Understand overall robot/past designs Understand communications program Look at current project site Understand team structures, roles,

responsibilities




CE Student 2 Understand overall robot/past designs Understand controller program Look at current project site Understand team structures, roles,

responsibilities




• During the first week of SD1, Wendy Fung and Jason Kenyon will give an overview of past designs and a quick run through on what a robot is.

• Current and past work will be easily referenced from each project’s web sites.

Option 3: CAN focused team (example team)

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Preliminary WBS (continued)

• Week One– Everyone

• Understand overall robot/past designs• Access EDGE website and add all RP1 projects

– ME Student 1 (Team Leader)• Refine team roles and responsibilities according to the

students involved• Get card access for all team members to necessary rooms• Identify long lead item• Assembly of baseline kit

– ME Student 2• Understand drive and steer systems• Begin designing test stand

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Preliminary WBS (continued)

• Week One (continued)– ISE Student 1

• Understand integration of the systems– EE Student 1

• Understand the power system– EE Student 2 & 3

• Research CAN protocol– CE Student 1 & 2

• Research CAN protocol

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Preliminary WBS (continued)• Week Two

– Everyone• Understand constraints, requirements, and expectations• Understand and adjust needs and specifications• Brainstorm ideas• Report to team on findings• Identify long lead times

– EE Students 2 & 3 and CE Students 1 & 2• Play with CAN protocol• Identify Dev board

– Other students• Appropriate equivalent workload unknown

• Week Three– Everyone

• Share design ideas• Build test fixtures• Preliminary selection of parts• Order long lead time parts

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Team Values and Norms• The default team values and norms are not expected to change unless circumstances

dictate otherwise.

– Each team member and every team must participate in collaboration to accomplish the goals of the RP1 Motor Module Project

– All students are expected to follow meeting guidelines including bringing all necessary documentation, pre-agenda and personal work expected to be done by meeting date.

– Punctual - Each team member will be prompt and arrive at the team meetings on time. If an unexpected conflict comes up, the absent team member will notify at least one team-mate prior to the expected absence. An absent team-member should confirm that a team-mate has received their message (in person, voice mail, email, etc).

– Thorough - Each team member will complete their tasks thoroughly and completely, so that the work does not have to be re-done by a peer on the team. If a member does not know how to complete a task, feels overwhelmed, or needs assistance then the member notifies peers, and seeks assistance either from a peer, the faculty guide, a faculty consultant, or another person.

– Accurate - Each team member completes their work accurately and in a way that can be easily checked for accuracy by peers and the faculty guide. All work is fully documented and easy to follow.

– Professional and Ethical - Each team member gives credit where credit is due. All work completed includes citations to appropriate literature, or sources of assistance. If a team member has gotten assistance from a publication or individual, then that assistance or guidance is fully documented in the reports prepared. Each team member is honest and trustworthy in their dealings with their peers.

– Demonstrates the core RIT values of SPIRIT.– Committed - Each team member will contribute an equal share to the success of the project.

• Each value is broken down to four levels of performance: Unsatisfactory, Needs Improvements, Meets Expectations, or Exceeds Expectations

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Grading and Assessment Scheme• Grading of students in this project will be fully consistent with grading policies established for the

SD1 and SD2 courses. The following level describes an absolute level of expectation for the design itself, for the hardware. However, the student team must also meet all requirements related to analysis, documentation, presentations, web sites, and posters, etc. that are implicit to all projects.

• Example for an Option 3: CAN-focused team:– Level D: The student team will deliver cost effective working motor module prototypes, capable of controlled

motion. The prototypes will be fully characterized. The motor module prototypes will meet customer specifications. The prototypes developed will be 100% open architecture and open source. They will use no proprietary components, only COTS components available from multiple manufacturers. A function generator is used to send out PWM signals.

– Level C: The student team will deliver all elements of Level D PLUS: The motor module prototypes will show quantitative improvements over the past motor modules for the customer's application. There will also be marked improvement over the past motor modules in the areas of control and user interface. The PWM signal is controlled by a CAN protocol.

– Level B: The student team will deliver all elements of Level D and C PLUS: The motor module prototypes will exceed the past motor modules in every aspect asked for by the customer. The prototypes will be interchangeable between at least other other team when placed on the platform.

– Level A: The student team will deliver all elements of Level D, C, and B PLUS: The team’s motor modules can be interchangeable with any other team’s motor modules. The CAN system can be switched out with SPI or I2C systems.

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Intellectual Property Considerations

• Everything associated with this project is public domain.

• The final result of the RP1 Motor Module design will be published for any party to access.

• The intent of publication is for any party to use the design to build their own Motor Module for their own use.

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Required ResourcesFaculty

Item Source Description Available Dr. Edward Hensel

ME Customer Yes

Dr. Wayne Walter ME Faculty Guide Yes Dr. Daniel Phillips EE Faculty Consultant Yes EE or CE Faculty Consultant Yes Environment Item Source Description Available Robotics Lab ME 09-2230 Workspace/Storage Yes Machine Shop ME 09-2360 Parts Fabrication Unknown CNC Labs Unknown Parts Fabrication Unknown Computer Labs Throughout CAD,

Programming, Etc. Yes

Equipment Item Source Description Available Power Supply EE or ME Used for testing Unknown Desktop PC EE Circuit analysis Yes Desktop PC CE or EE Programming Yes Desktop PC ME CAD and FEA Yes Voltmeter EE or ME Circuit testing Unknown 8Õ x 8Õ Table Unknown Test ing surface Unknown Static Mats EE (?) Static guard Unknown Oscilloscopes EE or ME Used for testing Unknown DC Motor Dynamometer

Unknown Used for testing Unknown

Material Item Source Description Available Baseline Kit Unknown Getting SD team

on track Unknown

Raw materials (plastic, wires, etc.)

Unknown Building materials (no long lead time)

Unknown

Boards (microcontrollers, PIC, etc.)

Unknown Electronic components

Unknown

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Identify Customer Needs

Some of our key customer needs: (out of 40+)

• Design should be modular: can interchange modules on single type of platform and operate in a similar manner

• Design should be open source and open architecture: all COTS items available from multiple sources and standard design documentation

• Design should power a robotic platform capable of carrying 1kg• All team designs should accept PWM signals to control motors• Design should have an infinite azimuthal steering angle• Design should minimize disassembly needed for component replacement• Design should have a professional look and feel• Design should be manufacturable in lots appropriate for it’s size (smaller payload

more manufacturable and higher quantity, less one-off)• All designs should utilize the same physical, electrical, and controls interface with the

platform• Design should be powered by on-board DC power source• Design should be easily recognizable as being a similar design concept to other RP

motor modules• Design should minimize weight and size appropriate to load capacity• Each motor module must be addressable and able to "talk" with a central processor.

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Preliminary Target Specifications

• Appropriate size for payload

Each module must fit within a size envelope

= 8” height x 4” length x 4” width

• Capable of powering a platform to carry a 1kg payload Torque to drive wheel is appropriate for payload and tare weight for a given speed and acceleration Specified drive motor torque is 2.72 lb-in, so drivetrain is up to SD students

• Turning radius of 0.15 m Each module must have an infinite azimuthal steering angle (as taken from customer need)

• Minimize need for disassembly for component replacement Should be able to access any component within 3 minutes of disassembly

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Cont…

• Design should be powered by DC power source• Communications specification:

– Minimum Criteria: All team designs should accept PWM signals to control motors

– Impressive: Each motor module must be addressable and able to "talk" with a central processor to control motors

• Design should minimize weight – 0.5 LB combined drive and steering motor + wheel approximate + building

materials + circuitry = approximately 1.5 kg target weight per module

• All designs should use components outlined in component kit:– Drive motor (Shayang Ye Industrial Co. IG320071-41F01)

– Steering motor (undecided)

– Drive wheel (undecided)

– Additional baseline components (pending)

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Cont…

• All designs should adhere to the overall RP Project family:

1) Constraint Objectives• Regulatory Constraints• Academic Constraints• Safety Constraints

2) Resource Objectives• People Resource• Equipment Resources• Materials Costs• Labor Costs

3) Scope Objectives

4) Technology Objectives

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Issues & Risk

• Taking on too much design responsibility – “biting off more than you can chew”• Budget Constraints – staying within budget, underestimating cost• Efficient use of resources (coordination) – machine shops, people’s schedules• Packaging envelope – teams must design within constraints• Scaled down version of previous designs – desired design should look like a miniature

version of previous designs• Customer expectations – miscommunication of/not meeting important needs• Time schedule (milestones to accomplish) – not meeting deadlines• High learning curve – too much to learn to accomplish goals• Identify and acquire key design components early – dependent components come after• Good design on paper but not in reality – CAD and other design work should be realistic• Testing capabilities – have time and testing equipment

• Not guaranteed that teams will collaborate – tension and design conflicts• Too much team collaboration will discourage uniqueness of design• Scheduling conflicts and difficult team meeting coordination• With some team structure options, the interface between segments will be difficult to

manage

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Outstanding Items

– Choose Multiple Team Structure– Finding interested students for the teams– Confirm IE student capabilities in their ability to design for manufacturing and manage

design interfaces– Establish relative importance of needs through follow-up surveys– Create expanded list of engineering specifications– Confirm project family customer needs and specifications:

• Will we adhere to the Prototype Configuration requirements? (Build 3 powered MM’s and 4 Idler MM’s)

• Size, speed, tare weight, design envelope– Consult with Dr. Phillips (EE Guide) about controls protocol assumptions after we

choose our Multiple Team Structure– Speak with Dr. Crassidis and Dr. Yang about their project needs– Establish interface standards (physical bolt pattern, electrical and communications

connectors)– Revisit 3 week Work Breakdown Structure after we choose our Multiple Team

Structure– Speak with Dave Hathaway about machine shop capabilities and lead time

requirements– Establish more baseline kit components – wheels?, steering motor? other materials

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Question

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Quick Electrical Disconnect

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Wing Nuts

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EMF Cage

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Tight Space

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Communications ProtocolsWe plan to establish a minimum standard that all teams must accept a PWM signal to drive their motor

module. However, there are many ways to deliver this PWM signal, and many ways to structure teams according to various protocols.

SPI:• Serial Communication Protocol – sends one bit at a time• High speed• Meant to be point to point communication, not in distributed environment where you might be talking to many

different points

CAN:• Serial Communication Protocol – sends one bit at a time• Meant to support network of connected devices• Developed for automotive application robust because of “Differential Pair” Communication• Ideal in applications with a lot of electrical noise• Need to have more intelligence in communications system to work with CAN can be more difficult to

implement

I2C• Low bandwidth, short distance protocol for on-board communication• Suited for many devices connected to a bus• 2 wires for connection – Serial Data and Serial Clock all devices must have individual “address”• Requires more wires than other protocols

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Communications Flowchart

Back

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Turntable

Back

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Internal Gear Pair

Back

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RP100 Platform

Back

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RP10 Platform

Back

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Target SpecificationsGeneral Specifications for all teams:

1. A single RP1 Motor Module will be capable of propelling a robotic platform which carries a payload of up to 1kg in weight:

1. Design is capable of variable speed from 0 to 4 inches per second

2. Design is capable of an acceleration of 4 in/s2 when propelling a platform carrying a 1kg weight

2. Design will be tested on a flat 8’ X 8’ surface

3. Design should fit within an 8” height X 4” length X 4” width size envelope

4. Motor Module design should weigh no more than 3 lbs each

5. Each team will deliver 3 Drive (powered) and 4 Idler (non-powered)

motor modules

6. Design should be open source: all documents and designs will be public

domain and all file types can be accessed by the public (eg. .IGES files

that can be used by multiple CAD packages instead of types that can only

be used by a single package)

6. Design should be open architecture: all commercial off the shelf (COTS)

components are able to be purchased from multiple vendors and all manufactured components are able to be fabricated using common technologies and tools

6. Design should have an infinite steering angle around a vertical axis

7. Should be able to access any component on the module with no more than 3 minutes of disassembly

Documents

Preliminary Project Plan P0820 2/5/6/7/8 – RP1 Motor Module