AX12A / AX18A Smart Robotic Arm - · PDF fileThe AX12A / AX18A Smart Robotic Arm is an original design from Alex Dirks of ... (located in the AX12A / AX18A parts bag) (2) #4 -5/8

2014 CrustCrawler Inc. AX12A / AX18A Smart Arm Manual V5.1

05/21/2014

AX12A / AX18A Smart Robotic Arm

Kit Assembly Guide

VERSION 5.1

Author – Alex Dirks

WARRANTY

CrustCrawler warrants its products against defects in materials and workmanship for a period of 30 days. If you discover a defect,

CrustCrawler will, at its option, repair, replace, or refund the purchase price. Simply call for a Return Merchandise Authorization (RMA) number, write the number on the outside of the box and send it back to CrustCrawler. Please include your name, telephone number,

shipping address, and a description of the problem. We will return your product, or its replacement, using the same shipping method used to

ship the product to CrustCrawler.

Robotis Servos

Robotis Servos are covered under the Robotis Warranty. All defects and/or repairs to damaged servos have to be claimed through Robotis

by their RMA process.

COPYRIGHTS AND TRADEMARKS

This documentation is copyright 2007 by CrustCrawler, Inc.

DISCLAIMER OF LIABILITY

CrustCrawler, Inc. is not responsible for special, incidental, or consequential damages resulting from any breach of warranty, or under any legal theory, including lost profits, downtime, goodwill, damage to or replacement of equipment or property, and any costs or recovering,

reprogramming, or reproducing any data stored in or used with CrustCrawler products. CrustCrawler is also not responsible for any personal

damage, including that to life and health, resulting from use of any of our products. You take full responsibility for your robotic application, no matter how life-threatening it may be.

INTERNET ACCESS

We maintain internet systems for your use. These may be used to obtain software, communicate with members of CrustCrawler, and

communicate with other customers. Access information is shown below:

E-mail: [email protected]

Web: http://www.CrustCrawler.com

Preface · Page iii


05/21/2014

Preface

The AX12A / AX18A Smart Robotic Arm is an original design from Alex Dirks of the CrustCrawler

team.

The CrustCrawler team assures you that when you successfully complete the AX12A / AX18A Smart

Robotic Arm you’re in for an exciting series of robotic projects that you will find highly rewarding. This is

our smartest, most advanced and powerful arm we have produced and we are sure you will find it a truly

functional robotic kit to meet your demanding robotic project needs!

Experience in programming is helpful, but if you need more help in this regard you can find plenty of

robotic programming resources on our web site (www.crustcrawler.com).

Support for your AX12A / AX18A Smart Robotic Arm, should you need it, is as simple as and e-mail

([email protected]). We encourage users of our products to use our web forum for each of our

product categories if you would like to ask a question or share information about your robotics project.

Our main number is our sales number and your questions will be answered in a more expedient manner in

our forum. Also, we can post pictures and code examples for you which cannot be done over the phone.

Chapter #1: Preparing to Assemble the AX12 / AX18A Smart Robotic Arm

REQUIRED TOOLS

The following tools will be required to build your AX12 SMART ROBOTIC ARM robotic arm:

� Phillips screwdriver

� A small amount of white grease or equivalent

� Thread locker (in either liquid or paste form)

� Needle nose pliers (small tip)

AX12 SMART ROBOTIC ARM FULL KIT INVENTORY

The AX12 / AX18A SMART ROBOTIC ARM base kit contains the following components:

Electronics\Software:

� (1) 12V – 5 Amp power supply (optional)

� (7) AX12A / AX18A Servos

Aluminum Parts:

� (1) Pivot Box

� (1) Turntable

� (1) Turntable lower brace

� (1) Turntable upper brace

� (1) Main beam

� (6) Base servo brackets

� (4) Short rotator servo brackets

� (2) 90 degree braces

� (1) Servo Forearm

� (1) Palm Bracket

� (2) Left Hand Grippers

� (2) Right Hand Grippers

� (4) Flat Braces

� (1) Gear Brace

� (1) Servo Gear Brace

� (1) Sensor Bracket

Nuts, Bolts, Washers Screws & Spacers

� (6) #2 nuts

� (10) #2 washers

� (6) #2 lock washers

� (2) #2 – 5/16” screws

� (2) #2 – ¼” screws

� (4) 14 MM screws & nuts

� (2) 10 MM screws

� (48) 5 MM screws & nuts (located in the AX12A / AX18A parts bag)

� (2) #4 -5/8”screws

� (2) #4 – 7/8” screws

� (2) #4 –3/8” screws

� (50) #4 - ¼” screws

� (1) #4 – ½” screw

� (13) #4 lock nuts

� (2) #4 5/16” nylon spacers

� (7) #4 1/8” nylon spacers

� (10) #4 washers

� (7) AX12A / AX18A servo pivot screws (1 screw per AX12A / AX18A parts bag)

Please note:

5mm screws and nuts are used throughout the construction process and can be found in AX12A / AX18A

Servo box

Miscellaneous

� (1) AX12 SMART ROBOTIC ARM Manual

� (8) Cable ties

� (2) 60 tooth Gear Sets

� (2) 12” extended servo cables

� (2) Gripper Padding

� (4) Turntable bearings

� (1) Turntable spacer

� (1) Gripper gear spacer

� (7) AX12A / AX18A Pivot spacer sets (1 set per AX12A / AX18A parts bag)


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Chapter #2: Pre-Assembly Tips

PAY ATTENTION TO DETAILS

• Work in a well lit, clean environment with lots of workspace

• Organize your nuts, bolts and screws so that you have each specific size of lock-nuts, screws, washers

in the same group and are easily within reach.

• Take your time! The AX12 / AX18A SMART ROBOTIC ARM robotic arm kit is a precision made

product and requires all parts to be assembled in the exact order as described in this installation

manual.

• The average time to construct a kit is between 3 to 6 hrs..

• During the construction process, please refer to the reference pictures in this guide frequently. Refer to

and study the pictures and close-up diagrams carefully before starting the construction of any part of

your kit.

• Always look “ahead” in the construction guide so you have a good idea of how the arm basically goes

together. Refer to the reference pictures at the end of this guide often as a reference when you are

constructing the AX12 Smart Arm.

• Always note the orientation and direction of screws and aluminum parts and which side of your

AX12 / AX18A SMART ROBOTIC ARM robotic arm you are constructing! It absolutely makes a

difference!

• If you have questions about assembling the AX12 / AX18A Smart Arm, please post your question to

our forum. Do not call our sales number as it is strictly for sales. Our forum is far more effective in

supporting you in that we can provide additional pictures and code quickly and easily for your

reference. We also have a large forum population that can also help you with your questions as well as

share projects and ideas.

The AX12A / AX18A Smart Servos

Congratulations on buying the most powerful and feature rich robotic arm kit available today! At the

core of the Smart Arm’s power and functionality is the AX12A / AX18A Smart Servos. With a built-

in microprocessor which allows multiple feedback capabilities and a range of voltages to operate

from, you will find this the most versatile arm you can buy today!

Some of the key features (but not all) include:

1. Full feedback on position, speed, load, voltage and temperature

2. Super fast 1,000,000 bps communication speed on single bus (no more multiple

servo wires!)

3. Full control over maximum torque, speed and movement in 1024 increments

4. Automatic shutdown based on voltage load or temperature

Note:

• Each servo must be assigned a unique servo address. This can be

accomplished using either your software or the Robotis Roboplus software

(Dynamixel Manager) which can be downloaded from either the Robotis

support web site (http://support.robotis.com) or their main product web site

at www.robotis.com.

• The default value of each Dynamixel before programming a unique servo

address is 1

• If you have any of the Robotis control boards or interface hardware such as

the USB2dynamixel, CM-700, CM-510 etc. you can use the RoboPlus

software to interface with, look at and change Dynamixel operating

parameters and assign unique servo ID’s .

• It is recommended that you assign a unique address to each servo before

building the AX Smart Robotic Arm.


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INSTALLING THE NUTS TO THE AX12A / AX18A SERVOS Installing the nuts into the slots of the AX12A / AX18A servo is best performed by using needle nose

pliers as shown in the picture below.

1. Place the nut into the slot of the AX12A / AX18A and ensure that the nut is sitting straight up and

down in the slot.

2. Place the lower tip of the needle nose pliers into the corresponding hole the nut was place into

(only half way ino the hole or it will push the nut).

3. Place the upper tip of the needle nose pliers onto the top of the nut and squeeze gently until the

nut “clicks” into place. DO NOT FORCE THE NUT OR YOU WILL BREAK THE PLASTIC

TAB.

4. If you are unsure if the nut is placed correctly into the AX12A / AX18A slot, simply look through

the plastic hole to ensure the nuts opening is aligned with the plastic holes opening.

Safety

• Always maintain a minimum distance of 3 feet from the farthest reach or your robotic

arm when powering and/or operating your robotic arm.

• Always disconnect power from your robotic arm before approaching and handling the

robotic arm in any way.

• Bolting the robotic arm down to a solid surface using the (3) tabs located on the base

of the turntable.


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SCREW INSTALLATION

Since the AX12A / AX18A robotic arm is a precise “joint” based design with lots of articulated

movement, it is highly recommended that every screw installed be coated in “loctite” thread locker (with

the exception of the #4 screws that have lock nuts installed). At CrustCrawler, we use Loctite 248 or 268

stick versions but any fluid or stick based Loctite product should work well. Loctite can be purchased at

most hardware stores.

NUT REPLACEMENT

If, during the installation of any of the #2 screws strips the nut of the AX12A / AX18A servo, the nuts can

be easily replaced. Simply remove the set screw of the servo and remove the servo horn by gently prying it

off with a small flathead screwdriver. Once the servo horn is removed, use a small screwdriver to gently

pry out the #2 nut. Replacement nuts can be found within the box of the AX12A / AX18A servo.

Set Screw

PREPARING THE AX12A / AX18A SERVOS

Each servo for the AX12A / AX18A Smart Arm will be installed based on its specific address. The

address can range from 1 to 7 or any range you would like to specify. Each servo address will be assigned

a specific location in the arms construction as shown in fig.1 below. Be sure to pay attention to the address

called out in the construction guide for each AX12 installation. Note: Servo addresses 2, 3 & 4, 5 can be

installed on either side of the arm (left side or right side).You must set a unique servo address for each

servo on the Smart Robotic Arm.

Figure 1 - Servo Adresses

1

3 2

4 5

6

7


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CONNECTING THE AX12A / AX18A SERVOS

The AX12A / AX18A servos have (2) male connectors on the back of each them. The left port is the input

port and the right port is the output port (see figure 2). The output port connects to the next AX12A /

AX18A servos input port. When building the AX12A / AX18A Smart Arm, be sure to follow the correct

connections for both input and output ports when connecting one AX12A / AX18A servo to another.

Note: The AX12A / AX18A servos must be connected in sequencial order (starting with address 1 and

ending with address 7) when building the AX12A / AX18A Smart Arm.

Figure 2

Figure 3

The example in illustrated in figure 3 shows the correct wiring of AX12A / AX18A servos from one

AX12A / AX18A to another starting with address #1 and connecting to addresses #2 and #3. (addresses 4 -

7 not shown)

Input port Output port

Note: Ensure that the servo horn indicator is aligned with the vertical mark on the AX12A /

AX18A servo body for all servos before installing them.

Servo horn

indicator

Vertical

mark


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Chapter #3: Smart Arm Assembly

1. Install (2) #2 nuts onto the AX12 / AX18A servo (address #1) into the second nut slot as shown in

figure #4 below.

Figure 4

2. Install the AX12 / AX18A servo (address 1) into the base using (2) 5mm screws (found in the

parts bag that comes with the AX12A / AX18A servo) and (2) #2 washers as shown in figure #5.

(be sure to use “Loctite” when installing these screws)

Figure 5

3. Place the (4) carbon steel ball bearings into the 1” circles of the base as shown in figure 6.

Figure 6


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Figure 7

4. Place the lower turntable brace onto the turntable (aligning the holes). Install the (4) 12mm screw

assemblies into each of the (4) holes as shown in figure 7. (The 12mm screws are contained with

the spacers and replace the 14mm screws, nuts and washers in your hardware kit as depicted in

the image above)

Figure 8

5. Obtain the turntable spacer as shown in figure 8.

12mm

Screws

6. Install the turntable spacer onto the other side of the assembly from the previous step by screwing

each of the (4) 2x12mm screws until each of the screws stick out of the turntable spacer about

1/16” as shown in figure 9

Figure 9

7. Install the turntable assembly to the turntable servo by aligning the (4) screws with each of the (4)

holes of the AX12 / AX18A servo and tightening each EVENLY until they are snug. DO NOT

OVERTIGHTEN! The finished assembly is shown in figure 10. Turn the turntable by hand to

enure it turns freely and easily and is resting evenly on the (4) turntable bearings (figure 10).

Figure 10

Turntable

spacer

This tab designates

the Front of the base


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8. Using (2) #4, ¼” screws and lock nuts, install the upper turntable brace to the lower turntable

brace as shown in figure 11. The upper turntable brace fits on the inside of the lower turntable

brace. Tighten the assembly so the assembly is stiff and can stay in any position.

Tip: Place the angle of the the upper turntable brace at 45 degrees or more to make further

construction easier. Once the arm assembly is completed, the set screws can be installed to both sides

of the assembly to secure the fixed angle you prefer.

Figure 11

#4- ¼” screw

and lock nut

9. Install (4) #2 nuts into the base of (4) AX12A / AX18A servos adddresses #2 thru #5 as shown in

figure 13.

Figure 12 – Base Servo Bracket

Figure 13

10. Using (4) 5mm screws, install the base servo bracket (figure 12) to the (4) AX12 / AX18A servo

addresses #2 thru #5 as shown in figure 14. (be sure to use “Loctite” when installing these screws)

Figure 14


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11. Install the nylon pivots and pivot spacers to (4) of the short rotator servo brackets as shown in

figure 15 and figure 16.

Note: It does not matter which side of the short rotator servo bracket the pivot and pivot spacer is

installed to.

Figure 15 – Pivot

Figure 16 – Pivot Spacer

Pivot

Pivot

Spacer

Note: Before installing the short rotator bracket, ensure that the servo horn indicator is aligned with the vertical mark on the AX12A / AX18A servo body as shown in figure 17. Failure to do so will

misalign the servos resulting in the parallel servos working against each other during arm

operation. Once aligned, install the short rotator bracket straight down onto the AX12A /

AX18A servo so that the inside screw is installed and aligned with the servo horn indicator as

shown in figure 19.

Also, ensure that all AX12A / AX18A servos are aligned in the manner described above before

installing.

Figure 17

Servo horn

indicator

Vertical

mark


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Figure 18

Figure 19

12. Using the servo set screw (located in the AX12A / AX18A servo box), install the short rotator

bracket to each of the (4) AX12A / AX18A servos as shown in figure 18. (thread locker is not

required for this step)

13. Using (4) 5mm screws, install the other side of the short rotator bracket to each of the (4) AX12A

/ AX18A servos as shown in figure 19. (be sure to use “Loctite” when installing these screws).

Servo Set

Screw

Inside

Screw

5mm

Screws

Install

straight down

14. The completed assembly is shown in figure 20.

Figure 20

15. Install a 12” extended servo wire into the left input port of AX12A / AX18A servo address #2 as

shown in figure 21.

Figure 21

12” servo

extension wire


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16. Using (4) #4, ¼” screws, install the AX12A / AX18A servo (address #2) onto the turntable upper

brace as shown in figure 22. Be sure to install the screws into the (4) integrated pem nuts of the

base servo bracket. Also, install the #4 – ¼” screws into the 1st and 3

rd hole from the edge of the

turntable upper brace. (be sure to use “Loctite” when installing these screws).

17. Install the shorter servo wire (from the AX12A / AX18A box) to the output port of the AX12A /

AX18A servo address #2 as shown in figure 22.

Figure 22

Servo wire from the

AX12A / AX18A box

18. Connect the 12” extended servo wire from servo address #2 to the output port of servo address

#1. Use the center hole of the 3 holes in the base to place the wire thru to the servo (see figure 23).

19. Plug the servo wire (from the AX12A / AX18A servo box) into the input port of servo address #1

and thread the wire thru the center hole of the base as shown in figure 23.

Figure 23

12” extended servo

wire from AX12A /

AX18A servo address

#2 input port

Servo wire from the

AX12A / AX18A servo

box


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Figure 24

20. Plug the shorter cable from the AX12A / AX18A servo (address #2) into the AX12A / AX18A

servo address #3’s input port. Plug a 12” servo extension cable into AX12A / AX18A servo

address #3’s output port.

21. Using (4) #4, 1/4” screws, install the AX12A / AX18A servo (address #3) to the opposite side of

the turntable upper brace using the same procedure as step 15. (figure 22.) (be sure to use

“Loctite” when installing these screws).

Figure 25

Figure 26 – Main Beam

Servo address 2 Servo address 3

(12” cable not

shown)


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22. Using (8) #4, ¼” screws (4 screws for each side), install the main beam (figure 26) to the short

rotator servo brackets integrated pem nuts of AX12A / AX18A servo addresses #2 and #3 as

shown in figure 27. Ensure that the main beam is centered before tightening all of the screws. (be

sure to use “Loctite” when installing these screws).

Note: Install the main beam with the opening (channel) of the main beam facing down (refer to figure

28)

Figure 27

Figure 28

Main beam

opening

This tab designates the

“front” of the AX12A /

AX18A Smart Arm


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23. Using (4) #4, ¼” screws, install AX12A / AX18A servo address #4 to the main beam as shown in

figure 29 (be sure to use “Loctite” when installing these screws) . Be sure to install the servo

assembly to the edge of the main beam before tightening the #4-1/4”screws.

Figure 29

Figure 30

24. Using (4) #4, ¼” screws, install AX12A / AX18A servo address #5 onto the other leg of the main

beam as shown in figure 31. (be sure to use “Loctite” when installing these screws)

25. Install the short servo cable from servo address #4’s output port (from the AX12 servo box) into

the input port of AX12A / AX18A servo address #5. Install the short cable (from the AX12 servo

box) into the output port of the AX12A / AX18A servo address #5.

26. Plug the 12” extended servo cable from AX12A / AX18A servo address #3’s output port into the

input port of AX12A / AX18A servo address #4. Route the cable through the hollow center of the

main beam. Do not tie rap the servos cables until the entire arm assembly is complete.

#4 screws

Figure 31 – Servo address #4 and #5

Figure 32 – The completed assembly


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27. Using (8) #4, ¼” screws, install the (2) 90 degree braces to each of the short rotator servo brackets

(4) pem nuts as shown in figure 33. Do not tighten the screws down as of yet. (be sure to use

“Loctite” when installing these screws)

Figure 33

90 degree braces

#4 – ¼” screws

28. Install (4) #2 nuts into the 1st and 3rd slots from the bottom of AX12A / AX18A servo address #6

as shown in figure 34. Repeat this step for the other side of the servo.

Figure 34

29. Using (8) 5mm screws, install the base servo bracket on each side of the AX12A / AX18A servo

address #6 as shown in figure 35. (be sure to use “Loctite” when installing these screws)

Figure 35


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30. Using (8) #4, ¼” screws, install the AX12A / AX18A servo address #6 to the (2) 90 degree braces

with the AX12A / AX18A servo oriented up as shown in figure 36. (be sure to use “Loctite”

when installing these screws)

31. Perform the same procedure as outlined in step 30 for the other side of the AX12A / AX18A

servo.

Figure 36

Tighten these (4) screws first. Tighten

the (4) screws on the other side of the

servo as well.

Tighten these (4) screws

and the 4 screws on the

other side once the servo is

centered (see figure 37).

Note: Ensure that the assembly is centered with the center of the main beam before tightening

all of the #4, ¼” screws that are attached to the short rotator servo brackets. Reference figure

37.

Figure 37 - Centered


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32. Using (4) 5mm screws, install the palm bracket to AX12A / AX18A servo address #6 as shown in

figure 38. (be sure to use “Loctite” when installing these screws)

Figure 38

33. Install (2) #2 nuts into the 2nd slots from the bottom of AX12A / AX18A servo address #7 as

shown in figure 39.

Figure 39


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34. Using (2) 5mm screws and (2) #2 washers, install AX12A / AX18A servo address #7 into the

palm bracket as shown in figure 40.

Figure 40

35. Install (2) #2, 5/16” screws into the pre-drilled plastic gear as shown in figure XX. Ensure to

install the screws into the odd spaced holes as shown in figure 41.

Figure 41

36. From the opposite side of the gear (figure 42), install (2) 10 mm screws into the remining (2)

holes of the gear until the end of the screws are even wit hthe surface of the inside of the plastic

gear as shown in figure 43.

Figure 42

Figure 43

37. Install the plastic gear spacer orienting the large holes onto the screw heads of the (2) #2 – 5/16”

screws as shown in figure 44.

Note:

When installing the plastic gear spacer, note the orientation of the #2 – 5/16”screw heads as it relates to

the spacing of the large holes of the gear spacer. Be sure to match them when placing the gear spacer onto

the gear.

Figure 44

2 X 10 mm

screws

The 10 mm

screws are even

with the surface

of the plastic

gear

Large holes


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38. Holding the gear head onto the plastic spacer with your fingers, fasten the spacer to the gear head

by tightening the (2) 10mm screws until the ends of the screws are sticking out from the other side

of the plastic spacer approximately 1/16” as shown in figure 45.

Figure 45

39. Place the gear assembly on top of the AX12 servo with the (2) #2 – 5/16” screws threads oriented

horizontally as shown with the dashed lines in figure 46. Tighten the (2) 2 X 10 mm screws until

the gearhead is firmly in place. (Do not overtighten!)

Figure 46

Correction – Remove the gear in figure 46 and rotate 180 degrees.

Place a #4 – 5/8” screw into the middle hole of the other gear and slip a #4 - 1/8” nylon spacer onto

the #4 – 5/8” screw as shown in figure 47.

Figure 47

40. Using the #4 pem nut on the palm assembly as shown in figure 48 , install the gear assembly from

step 40 with the exposed screw threads oriented horizontally as shown in figure 49. Secure the

screw using a #4 lock nut.

Note: Tighten the #4 lock nut just enough to tighten the assembly but not too tight that it makes turning the gear

stiff. To check for stiffness of the gear, loosen the (2) #2 – 5mm screws of the gripper servo until the gear

disengages from the other gear and turn the gear by hand. Adjust the #4 lock nut as nessassary before re-

engaging the gear sets.

Figure 48

#4 - 1/8” nylon

spacer

#4 - 5/8”

screw

#4 Pem nut


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Figure 49

41. Using (2), #2 lock washers and nuts, install the gripper brace with the larger center hole to the

AX12A / AX18A servo gear as shown in figure 50.

Figure 50

Exposed #2 screw

threads for both

gears are aligned

horizontally

42. Using (2) #2 lock washers and nuts install the other gripper brace to the other gear as shown in

figure 51.

Figure 51

43. Install the (2) Flat Braces to the left hole of the palm bracket in the numbered order shown in

figure 52.


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Figure 52

Note: For smooth and frictionless assembly, use a small amount of light grease between parts when

assembling the moving parts of the gripper assembly.

1. #4 – 7/8” screw

2. Flat Brace

3. (2) #4 washers

4. (1) - #4- 5/8”

Nylon spacer

5. Flat Brace

6. (1) #4 -1/8” Nylon

spacer

7. (1) #4 washer

8. #4 Lock Nut

Figure 53

44. Repeat step 44 for the other (2) flat braces to be installed in the #4 hole shown in figure 53.

Tighten both assemblies so the assemblies are a bit stiff and stay in place (Figure 54). Later in the

construction process, the lock nuts in the gripper assembly will be “tuned” and adjusted.

Figure 54


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45. Using (2) #2 – ¼” screws, lock washers and nuts, install the gripper servo brace to the palm

assembly as shown in figure 55. Install a #4 – ½” screw to the pem nut until the screw rests

against the AX12A / AX18A servo (see figure 56) (use Loctite for this step).

Note: Do not over tighten!!

Figure 55

#2 lock washer

and nut

#4 – ½” screw

Figure 56


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46. Using (4) #4-1/4” screws, assemble the gripper paddles as shown in figure 57.

Figure 57

47. Peel the backing off of the rubber gripper pads and place each gripper paddle down onto the

sticky side of the rubber pads. Press down firmly to ensure an even and solid bond with the

gripper paddles (figure 58).

Figure 58

48. Using a pair a scissors, trim the rubber padding around the gripper paddles as shown in figure 59.

Figure 59

Note: The slots on the inside of each of the gripper paddles can be trimmed out if you are going to

mount sensors to this area. This can be best accomplished with an Exacto knife.

49. Using (1) #4 – 3/8” screw (1) washer and (1) lock nut, install the left paddle to the gripper

assembly as shown in figure 60. Perform this step for the other gripper assembly for the opposite

side.

Figure 60

1.#4 – 3/8” screw

2. Left gear brace

4. (1) #4 washer

5. (1) #4 lock nut

3. Left Gripper

Paddle


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Figure 61

Figure 62

50. Using (1) #4-5/8” screw, (2) #4 – 1/8” nylon spacers and (1) #4 lock nut, install the left gripper

paddle to the flat braces following the numbered order as shown in figure 63. Repeat this step for

the other gripper paddle on the opposite side of the assembly.

Figure 63

1. #4 – 5/8” screw

2. Flat brace

3. #4 – 1/8” nylon

spacer

4. Gripper assembly

5. #4 – 1/8” nylon

spacer

6. Flat brace

7. #4 lock nut


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• The completed gripper assembly

Figure 64

51. Using (2) #4 – ¼” screws and lock nuts, install the sensor stand to the top of the gripper assembly

as shown in figure 65.

Figure 65


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TUNING THE GRIPPER ASSEMBLY

Once the gripper assembly is complete, “tuning” of the gripper assemblies lock nuts is required for

optimum performance and reliability. It is especially important that the gripper assembly is not too tight or

overheating of the servo can occur during operation.

• Ensure that all of the #4 lock nuts of the gripper assembly are not tightened down to the point that

makes the gripper difficult to move with your hands. The #4 lock nuts should be tightened just

enough to ensure that the screw assembly the nut holds is not loose but not too tight in that the

assembly has difficulty moving. Check the lock nuts shown in figure 66 for proper tightness.

Figure 66

1

2

3

5

6

4

Plug the cable from AX12A / AX18A servo address #6 output port into AX12A / AX18A servo address

#7 input port.

CHECKING GRIPPER ALIGNMENT

• Close the gripper assembly until the gripper ends touch each other. Ensure that the grippers are

even with each other at the point of contact as shown in figure 67. If the gripper end points are

uneven, loosen the (2) #2 screws holding the gripper servo in place, loosen the #4 set screw and

slide the gripper servo to the left and rotate the opposite gear head clockwise or counterclockwise

to align the grippers. Once aligned, move the servo back into place and tighten the (2) #2 screws.

Figure 67


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SETTING THE INITIAL ANGLE OF THE AX12A / AX18A SMART ARM

Set the initial angle of the AX12A / AX18A Smart Arm and secure the position with (2) #4 – ¼” screws

and lock nuts as shown in figure 68. At CrustCrawler, we prefer a forward lean angle for the arm as

depicted in figure 68.

Figure 68

#4 – ¼

screw

WIRE ROUTING AND TIE WRAPPING THE AX12A / AX18A SERVO WIRES

Now that the arm assembly has been completed, ensure to route and secure the AX12A /

AX18A servo wires so they do not interfere with the free movement of the AX12A / AX18A

Smart Arm. Make sure that the up and down motion of the (2) wrist servos (address #4 and

#5) are free to move in both directions to their maximum positions before securing their

servo wires to the main channel.

Use the holes of the main channel to secure the “loops” of wires for servo address 2, 3, 4 and

5 as shown in figure 69, 70 and 71.

Figure 69

Tie raps


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Figure 70

Figure 71

Mounting the AX12A / AX18A Smart Arm

CAUTION!

Always mount the AX12A / AX18A Smart Arm to a secure base or robotic platform using

the (3) mounting tabs located on the base of the Smart Arm before operating the arm! Always

stay at least 3 feet away from the arm during operation (see image below). Failure to do so

may result in injury to you and damage to the arm!!

Mounting

Tabs


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REFERENCE PHOTOS


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Programming the AX12A / AX18A Smart Arm

There are any number of ways to program and control the AX12A / AX18A smart arm.

For all of the latest downloads and software using the Robotis CM-700, CM-510 and

USB2dynamixel drivers, please go to the Robotis support web site at:

http://support.robotis.com

Powering Your AX-12 Smart Arm

The AX-12 Smart Arm requires a separate power supply that can deliver 12volts at 5 amps.

The AX-12 Smart arm cannot be powered by the USB2Dynamixel on your USB port, nor

can it be powered by the power supply that is bundled with the Parallax Propeller Demo

board (if of course you purchased these options). CrustCrawler does sell an AX-12 / AX18A

Power Supply and AX-12 / AX18A Power Supply Harness (found on the “Accessories” tab

of the AX-12 product page or the AX-12 Smart Robotic arm product page).


05/21/2014

Connecting Power to Your AX-12 Smart Arm

(For users supplying their own power)

Figure 72 depicts the pinout of the AX-12 / AX18A cable coming from the base rotate servo

(address #1). Use tweezers or a pin to remove the + and – power lines from the Molex

connector. Be sure to remove one cable at a time and label each one appropriately before

removing the next cable from the Molex connector. Once removed and labeled, connect the +

and – cables to your own power supply.

Figure 72

AX-12 Signal line

+

-

Connecting the AX-12 / AX18A Smart Arm to a Microcontroller

When connecting the signal line of the AX-12 Smart Robotic arm to a microcontroller, a few

simple components are required:

(1) – 10k resister (brown, black, orange)

(1) – 1k resister (brown, black, red)

(1) - Jumper wire

• Step 1 – Connect the 10k Resister to VDD of your microcontroller power bus

• Step 2 – Connect the 1k resister to your output signal port of your microcontroller

• Step 3 - Connect the other two ends of the resisters together on a common bus (as

shown in the example using the Parallax Propeller Demo board)

• Step 4 – Connect the signal line from AX-12 servo address #1 to the common bus

from step 3.

• Step 5 – Start programming!

1K Resister

10K Resister

To AX-12 Signal line


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Operating Tips

• When operating the AX series of Smart Robotic Arms it is important to understand

that when the arm is placed in a “load” position for a long period of time (ie: the arm

is position horizontally, picking up a load etc), the AX-12A/ AX-18A servos will

eventually heat up and shut down over time.

• This is especially true of the servo placed in the shoulder position as it has to carry

the largest load of all of the servos on the robotic arm. To avoid overheating any of

the servos, a good practice while operating the arm is to place the arm in a rest

position (straight up) when the arm is not operating between movements.

• When an actuator overheats it is placed in “thermal shutdown” by the servos

controller board to protect the motor from damage. Thermal shutdown is indicated by

a blinking LED at the back of the servo, the servo turns off its torque and the servo

goes limp.

• When in thermal shutdown mode, allow the servo to cool for a few minutes before

resetting the arm (turning off and then on the power source for the robotic arm).

Safety

• Always maintain a minimum distance of 3 feet from the farthest reach or your robotic

arm when powering and/or operating your robotic arm.

• Always disconnect power from your robotic arm before approaching and handling the

robotic arm in any way.

• Always bolt down the robotic arm to a solid surface using the (3) tabs located on the

base of the turntable.

Documents

AX12A / AX18A Smart Robotic Arm - · PDF fileThe AX12A / AX18A Smart Robotic Arm is an original design from Alex Dirks of ... (located in the AX12A / AX18A parts bag) (2) #4 -5/8