SG5-UT Robotic Arm - CrustCrawler · PDF fileSG5-UT Robotic Arm ... Constructing the Gripper Assembly ... • Remove the aluminum body parts from their protective bags and lay them

SG5-UT Robotic Arm Kit Assembly / Testing and Programming Guide

VERSION 3.1

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.

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COPYRIGHTS AND TRADEMARKS This documentation is copyright 2004 by CrustCrawler, Inc. BASIC Stamp is a registered trademark of Parallax, Inc. If you decided to use the name BASIC Stamp on your web page or in printed material, you must state that "BASIC Stamp is a registered trademark of Parallax, Inc." Other brand and product names are trademarks or registered trademarks of their respective holders.

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 BASIC Stamp and robotic application, no matter how life-threatening it may be.

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Table of Contents · Page i

Table of Contents

Preface.................................................................................................................................................. iii Chapter #1: Preparing to Assemble the SG5 Robotic Arm.............................................................. 1

Required Tools...................................................................................................................................... 1 SG5 robotic arm Full Kit Inventory ........................................................................................................ 1 Additional Parts you need to supply...................................................................................................... 4

Chapter #2: Pre-Assembly Tips .......................................................................................................... 5 Pay Attention to Details......................................................................................................................... 5 Preparing the Servos ............................................................................................................................ 6

Chapter #3: Building The Base ........................................................................................................... 7 Mounting the Servo to the Pivot box ..................................................................................................... 7

Chapter #4: Building the Bicep’s ...................................................................................................... 17 Chapter #5: Adjusting the Biceps Servos........................................................................................ 30 Chapter #6: Constructing the Forearm Assembly .......................................................................... 36 Chapter #7 – Constructing the Gripper Assembly.......................................................................... 45 Chapter #8 – Installing the Gripper Assembly to the Forearm Assembly .................................... 65 Chapter #9 – Retention Spring Installation and Servo Wire Routing............................................ 67 Reference Pictures ............................................................................................................................. 72 SG5 Robotic Arm Safety and Operational Tips ............................................................................... 75

Preface · Page iii

Preface The SG5 robotic arm is an original design from Alex Dirks of the CrustCrawler team. Experience programming the BASIC Stamp 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). All of the sensors we sell include BASIC Stamp program examples which you could readily adapt to the SG5 robotic arm. Great resources for electronics can be found at Mouser www.mouser.com and Digikey (www.digikey.com). Batteries and chargers can be found at as well as an optional power supply for the SG5-UT arm can be found on the Crustcrawler web site. Support for your SG5 arm, should you need it, is as simple as and e-mail ([email protected]) or phone call away. We have also provided a web forum for each of our product categories if you would like to ask a question or share information about your robotics project. The CrustCrawler team assures you that when you successfully complete the SG5 robotic arm you’re in for an exciting series of robotic projects that you will find highly rewarding. Our office staff has customized the SG5 robotic arm by adding, cameras, ultrasonic sensors, pressure sensors and infrared detectors to make it a truly interactive platform. We are sure that you will find our SG5 series robotic arms to be a truly expandable and functional robotic kit.

Chapter 1: Preparing to Assemble the SG5 robotic arm · Page 1

Chapter #1: Preparing to Assemble the SG5 Robotic Arm

REQUIRED TOOLS The following tools will be required to build your SG5 robotic arm:

Phillips screwdriver Drill 1/8” drill bit Small adjustable crescent wrench or socket set Wire cutters A small amount of white grease or equivalent

SG5 ROBOTIC ARM FULL KIT INVENTORY The SG5 base kit contains the following components:

Electronics\Software:

(3) HiTec HS-475 HB Servos and 3 HiTec HS-645 MG servos. Servo Wire Extensions – (2) 12” , (1) 6” (1) SPST switch

Aluminum Parts:

(1) Board Holder (1) Pivot Box (1) Lower Servo Pivot table (1) Upper Pivot Table (2) Servo Table Braces (2) Servo Pivot Braces (1) Pem Stud Bicep (1) Servo Bicep (1) Pem Stud Forearm (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 (1) Lower arm brace (1) Upper Arm Brace

Page 2 · SG5 robotic arm Kit

Nuts, Bolts, Washers Screws & Spacers

(4) #2 nuts (4) #2 lock washers (4) #2 -5/16”screws (34) #4 washers (13) #4 -1/2” screws (12) #4 –3/8” screws (26) #4 - ¼” screws (4) #4 – 1” screws (1) #4 – 5/8” screw (1) #4 – 5/16” screw (17) #4 nuts (23) #4 lock nuts (17) #4 lock washers (12) #4 ¼” nylon spacers (4) #4 5/16” nylon spacers (8) #4 3/16 nylon spacers (14) #6 –3/8” screws (1) #6 – ¼” screw (8) #6 lock nuts (8) #6 nuts (8) #6 lock washers (1) #6 washer (3) ¼” SAE flat washers (4) Support Knobs

Miscellaneous

(1) SG5 robotic arm Manual (10) Cable ties (1) Long Retention Spring (1) Short Retention Spring (2) 60 tooth Gear Sets (4) Rubber Bumpers (2) Gripper Padding

Chapter 1: Preparing to Assemble the SG5 robotic arm · Page 3

Source Code from the CrustCrawler Web Site (www.crustcrawler.com)

SG5 Robotic Arm Source Code

The CrustCrawler web site and the SG5 robotic arm page contains sample BS2P-IC source code, this installation guide and additional pictures of the SG5 robotic arm to aid you during the construction process.

Projects and Accessories are available from the CrustCrawler web site (www.CrustCrawler.com)

SG5 Robotic Arm Projects / Accessories

Projects that include updated code; electronics and hardware accessories are always being added to the Crustcrawler web site. Check with our site often for the latest updates.


ADDITIONAL PARTS YOU NEED TO SUPPLY Like other hobby kits, completing the SG5 robotic arm kit requires additional parts that you will need to supply. This hardware is not included in the SG5 kit because it would only drive the cost higher as most of these items are readily available at hobby stores or www.crustcrawler.com.

• 5 V NiMH or NiCd six-cell rechargeable battery for servo power. This is a standard 1800 mAH to 3000 mAH battery pack, commonly used in R/C cars. A good source for this product is Tower Hobbies (www.towerhobbies.com). Expect to pay between $30 and $60. Or, you can go to Radio Shack who also sells good quality 5V NiMH batteries and chargers. Also note, servo’s work best when using a regulated power supply or the servos may “twitch” during operation. A regulated power supply or a 5v voltage regulator connected between the battery and the PSC controller work very well. Crustcrawler has an excellent 6v, 2.5 amp power supply which has been customized for the SG5-UT robot arm system. See our web site for details.

• AC/DC Digital Peak Charger for the 5 V NiCd/NiMH battery. CrustCrawler carries an excellent charger from Hi-Tec. Refer to our web site for details.

• Zip-ties of the smaller sizes are very useful for securing wires in a tidy fashion. Approximate cost is probably a few dollars. Available from any hardware store. (10) Zip ties have been included in your kit.

• Robot sensors The SG5 robotic arm has been designed for sensor integration. Selecting the appropriate sensor is left up to you, our customer. CrustCrawler (www.crustcrawler.com) has many acceptable add-on sensors for the SG5. Additional sensors can be purchased from Parallax (www.parallax.com).

• Light grease A small amount of white grease or it’s equivalent is helpful when assembling the gripper portion of the arm and the base.

Chapter 2: Pre-Assembly Tips · Page 5

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 SG5 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 note the orientation and direction of screws and aluminum parts and which side of your SG5 robotic arm you are constructing! It absolutely makes a difference!


PREPARING THE SERVOS • Remove the aluminum body parts from their protective bags and lay them loosely in their respective

groups on your work surface.

• Gather all (6) of the servos and remove the servo horn and screw, setting them aside in a safe place.

Note: (1) of your Hitec HS-475HB servos will not contain a round servo horn. Use this servo for the palm assembly as it requires a pre-assembled gear head contained in your kit.

• Remove the riser tabs from (3) HiTec HS-475HB and (3) HiTec HS-645MG servos as shown below. The removal of this plastic riser will allow the servo to sit flush against the servo holder. These servos will be installed in the next few steps of the construction process.

Figure 1

Chapter 2: Pre-Assembly Tips · Page 7

Chapter #3: Building The Base

MOUNTING THE SERVO TO THE PIVOT BOX

Figure 2 – Mounting the servo

1. Using (2) #6 – 3/8” screws and lock nuts, secure the HiTec HS475HB servo to the pivot box as shown in figure 2. Ensure that the servo is mounted so that the servo horn mount is in the center of the pivot box as shown in figure 3. Thread the servo wire thru the center slot of the pivot box.

Figure 3

#6–3/8” screws

#6– nylon lock nuts

Servo Wire


2. Using (2) #4 3/8” screws, washers, lock washers and nuts, install the board holder to the pivot box

as shown in figure 4. Before tightening the #4 screws, install the (4) rubber bumpers to the bottom of the board holder and (if necessary) adjust the board holder so that it sits flush with your work surface. Tighten the #4 screws.

Figure 4

#4–3/8” screws

Mounting Slots

Board Holder

Chapter #2: Program the SG5 robotic arm · Page 9

3. Using (4) 5/16” #4 nylon spacers and washers, install the support knobs to the (4) integrated pem

nut holes located at the top of the pivot box as shown in figure 5. Hand tighten the support knobs. Do not use pliers or other tools to tighten the support knobs.

Figure 5

Support Knobs

5/16” #4 Nylon Spacer


Figure 6 – The completed pivot box assembly

4. Add a liberal amount of grease to the top of the support knobs as shown in figure 6. Temporarily set the pivot box assembly to the side of your work area.


5. Using a 1/8” drill bit, drill out the holes of the servo horn that match the holes in the lower servo pivot table as shown in figure 7.

Figure 7

6. Using (4) 3/8” screws and lock nuts, mount the servo horn to the lower servo pivot table as shown

in figure 8. The servo horn should be mounted on the pem nut side of the lower pivot table (see figure 10).

Figure 8

3/8” #4 Screws

#4 Lock Nuts

Servo Horn


7. Mount the lower servo pivot table onto the servo of the pivot box assembly and turn the lower

pivot table clockwise and counter-clockwise to spread the grease evenly to the bottom of the pivot table as shown in figure 9.

Figure 9


8. Remove the lower servo pivot table and spread grease with your finger onto any spot formed by

the circle of grease that may appear thin or uneven as shown in figure 10. Re-apply a small amount of grease to the tops of the support knobs. Re-install the servo pivot table to the pivot box. Do not secure the servo pivot table with the servo screw at this time.

Figure 10


9. Temporarily install the lower pivot table to the servo box with one of the pem nuts of the lower

pivot table aligned with the center slot (located on the board holder side) of the pivot box. Rotate and orient the lower pivot table so that it can rotate evenly 90 degrees in either direction from the center slot as shown in figure 11.

Figure 11

10. Once the lower pivot table is oriented correctly secure the lower pivot table with the stock servo

screw. DO NOT over-tighten the servo screw. Tighten the servo screw to the point that the round pivot table can turn freely but is not loose enough in that it does not make contact with all of the (4) pivot points.

Rotate 90 Degrees

clockwise

Rotate 90 Degrees counter -

clockwise

Pem nut – center point


11. Using (8) #4 ½” screws, nuts and 3/16” nylon spacers, install the Parallax micro controller board,

basic stamp, Parallax Servo Controller (PSC), (1) SPST switch (optional) and the male power supply receptacle (if you purchased the optional 6v, 2.5 amp power supply – see figure 12b) to the board holder. Your micro controller board and servo controller should be oriented as shown in figure 12. The board holder was made for all of the Parallax micro controller boards and the PSC servo controller. If you have a micro controller board that does not fit the slots on the board holder, simply drill out the appropriate holds with a 1/8” drill bit.

Note: We have provided (1) single pole, single throw (spst) switch for your convenience. Power for the servos can be routed directly to the PSC controller or through the switch and then to the PSC. The switch is optional and is not required for arm operation.

Figure 12


Figure 12b


Chapter #4: Building the Bicep’s

Note: For the next step, use the Hitec HS-645MG servos.

12. Using (2) #6 screws and lock nuts, install the Hitec HS645 MG servo to the servo bracket with the servo oriented as shown in figures 13 and 14.

Figure 13 – Left Side servo bracket assembly orientation

Figure 14 – Right Side servo bracket assembly orientation

3/8” #6 Screws

#6 Lock Nuts

Servo Bracket


Note: For the next step, use the servo horn from the Hitec HS-645MG servos.

13. Using a 1/8” drill bit, drill out the center hole of the 3-hole pattern on the round servo arm for (3) servo horns as shown in figure 15. To make drilling easier, use an unused servo and attach the servo horn to the servo before drilling.

Figure 15


14. Using (2) ¼” #4 screws and lock nuts, mount the flat side of the round servo horn to the pem stud bicep as shown in figure 16. (the pem stud bicep is the bent arm with the round aluminum spacer integrated into one end). Ensure that the servo arm is installed on the inside of the bend of the pem stud bicep as shown in figure16.

Figure 16

¼” #4 Screws

#4 Lock Nuts


15. Install the pem stud bicep to the “left side” servo/bracket assembly as shown in figure 17. Before

securing the pem stud bicep with the stock servo screw, ensure that the arm can rotate evenly in both directions from the 90-degree position (at least 45 degrees in either direction from the 90 degree position).

Figure 17

Stock Servo screw

Pem stud bicep


16. Using (4) ¼” #4 screws and lock nuts, install the 2 round servo arms to the servo bicep as shown

in figure 18. Ensure to note the orientation of the servo arm as it relates to the sides of the servo bicep when installing. Always install the servo arms with the flat side flush with the aluminum piece you’re mounting it to.

Figure 18

¼” #4 screws

#4 lock nuts


17. Install the servo bicep to the “right” servo / bracket assembly as shown in figure 19. Before

securing the servo bicep with the stock servo screw, ensure that the arm can rotate evenly in both directions from the 90-degree position (at least 45 degrees in either direction from the 90 degree position).

Figure 19

Stock Servo Screw

Servo Bicep


18. Using (4) ¼” #4 screws install the lower arm brace (the longer of the 2 braces) in the center of the

2 biceps as shown in figure 20.

Figure 20

¼” #4 screw

Lower Arm Brace


19. Using (4) 3/8” #4 screws, washers, lock washers and nuts, install the assembly in figure 19 to the upper pivot table as shown in figure 21.

Note: Do not tighten the screws until the assembly is centered in the slots of the upper pivot table.

Figure 21

3/8” #4 screw

#4 washer, lock washer and nut

Servo brace


Reference figure 22 and figure 23 and 23b to ensure accurate assembly

Figure 22


Figure 23


Figure 23b


20. Using (3) ½” #4 screws and ¼” #4 nylon spacers, install the assembly from 23b to the lower pivot table as shown in figure 24.

Figure 24

1/2” #4 screw

1/4” #4 nylon spacer


Refer to figure 25 to ensure accurate assembly.

Figure 25


Chapter #5: Adjusting the Biceps Servos

Since servos have different tolerances, it is necessary to physically and programmatically adjust for these differences especially if 2 servos are working in parallel as the biceps servos do. Regardless of the micro controller used, these steps are crucial to ensure proper operation and long servo life. The example below uses the Parallax servo controller (PSC), a BS2P24 module and the Board of education (BOE) board.

21. Remove (2) of the ¼”, #4 screws from one side of the lower arm brace. Connect the Parallax PSC

to the Board of Education (slot 15 on the BOE) and connect the 2 servos on the upper pivot deck to PSC ports 1 and 2. Refer to your PSC and BOE documentation for more information on how to connect and operate this hardware.

BOE Connection


22. Ensure that the PSC power switch is in the off position and the Parallax Board of Education (BOE) is switched off (when applicable). Connect 5v power to the PSC controller and 9v power to BOE.

PSC Connection


23. Since all servos have different physical tolerances, the following Pbasic program is used to ensure

that the 2 bicepts are physically parallel to each other during arm operation. After running the program and you have determined that the arms are as physically close to parallel as possible, ensure that you write down the 2 servo values if they are different. The 2 values that you write down will need to be used for all programs that are created for controlling the arm.

Note: If you find that the difference in values of the servos is substantial (approximately more than 25), physically adjust the bicep located on the outside of the assembly. Adjustment is obtained by removing the servo screw and bicept from the servo spindle and then physically rotating the bicep so it aligns with the other bicep as close as possible. ‘{$STAMP BS2} ‘This program is used to programmatically adjust the 2 upper pivot deck servos in ‘case they cannot be aligned physically. This step is crucial to ensure long servo ‘life and low current consumption. If the servos are not aligned properly, they will run ‘hot and use more current than what’s required for normal operation. ‘Here are the steps to physically and programmatically adjust the servos: ‘1. Download the program “as is” to your basic stamp ‘2. Observe the differences between the positions of the biceps ‘3. Physically adjust just one biceps to match the other biceps position as ‘ much as possible by removing the biceps from the servo spindle, rotating it clockwise ‘ or counterclockwise and then place it back onto the servo spindle) ‘4. Programmatically adjust just one of the values (position0 or position1)so the ‘ Biceps are as close to parallel as possible. ‘5. Write down the different values for position0 and position1 for future programming. ‘Notes: I have found that servos vary 15 to 20 steps from each other. As an example, ‘Position0 = 750 and position1 had to be adjusted to 735 for the 2 biceps to match ‘(or vise versa depending on which value you choose to adjust) ‘----------------------------------------------------------------------------------- servo1 CON 0 servo2 CON 1 ramp CON 11 Sdat CON 15 baud CON 1021 position0 VAR Word position1 VAR Word position0 = 750 ‘adjust just one of these values to align one bicep with the other bicep position1 = 750


SEROUT Sdat,Baud+$8000,[“!SC”, servo1, ramp, position0.LOWBYTE, position0.HIGHBYTE, CR] SEROUT Sdat,Baud+$8000,[“!SC”, servo2, ramp, position1.LOWBYTE, position1.HIGHBYTE, CR] END


Use the lower arm brace hole as the alignment tool for this operation. Figure 26 and Figure 27 illustrate incorrect and correct arm alignment. Once the arms are aligned, re-install the (2) #4, ¼” screws to the lower arm brace and write down the values used in the program for the 2 servos.

Figure 26 – Incorrect Alignment


Figure 27 – Correct Alignment


Chapter #6: Constructing the Forearm Assembly

1. Using (2) ¼” #4 screws and lock nuts, install the servo pivot brace to the pem stud forearm

ensuring that the large center holes are aligned as shown in figure 28. Ensure to install the servo pivot brace with the small hole located towards the end of the arm as shown in figure 28.

Figure 28

1/4” #4 screws

#4 lock nuts

Ensure Hole Alignment

Hole


2. Using a 5/16” #4 screw, washer, lock washer and nut, install the short retention spring to the

servo pivot brace. Ensure that the washer clears the top of the springs coil and sits flush with the springs loop as shown in figure 29.

Figure 29

5/16” #4 screw

#4 washer

#4 nut #4 lock washer

Short Retention Spring


3. Install (2) #4 SAE flat washers to the pem stud bicep as shown in figure 30. Apply grease to the outside of the last washer. Ensure to install the washers so the flat sides of the washers will be touching the aluminum arm components.

Figure 30

Pem stud #4 SAE washers


4. Using (1) ¼” #6 screw and washer, secure the assembly from figure 29 to the pem stud as shown in figure 31.

Note: A small drop of “Lock-Tight” applied to the threads of the #6 screw before it is installed will help to ensure that the screw does not come loose during continued operation of the SG5 arm.

Figure 31

¼” #6 Screw

#6 Washer

Pem Stud


The completed assembly.

Figure 32


5. Using a 1/8” drill bit, drill out the center hole of the 3-hole pattern on the servo arm as shown in figure 33.

Figure 33

6. Using (2) ¼” #4 screws and lock nuts, install the servo arm to the inside of the servo forearm

as shown in figure 34. (Flat side of the servo arm mounted to the servo forearm)

Figure 34

¼” #4 Screws

#4 lock nuts


7. Using (4) #6 – 3/8” screws, lock washers and nuts, install the HiTec HS-645MG servo to the servo pivot brace and the servo forearm as shown in figure 35.

Warning! Failure to mount the servo on top of the servo pivot brace will result in the rest of the assembly not fitting together correctly

Figure 35

#6 nut

#6 Screws

Servo Forearm

#6 lock washer

Servo Pivot Brace


8. Once the assembly is complete, install the completed assembly from figure 35 into the servo

horn and pem stud of the bicep assembly and ensure that the forearm assembly can rotate freely from the 90-degree position (straight up in the air) to 90+ degrees forward position. Secure the servo with the stock servo screw.

Reference figure 36 and figure 37 to ensure accuracy of your assembly.

Figure 36

Free Rotation


9. Using (4) ¼” #4 screws, install the forearm brace to the forearm assembly with the straight

edge of the brace facing away from the incomplete forearm assembly as shown in figure 37.

Figure 37

10. Using (4) ¼” #4 screws and lock washers, re-install the lower arm brace.

Forearm Brace

Lower Arm Brace


Chapter #7 – Constructing the Gripper Assembly

As you are constructing the gripper assembly, refer to pictures in figures 52 to 57 as a

reference. 1. Using (2) ¼” #4 screws, assemble the (2) gripper assembly’s as shown in figure 38.

Figure 38

2. Install the 1/16” rubber padding to the insides of the gripper assemblies. Be sure to cut out the

slots on the insides of the grippers. Also, ensure that you cut as close to the edge of the grippers as possible to obtain a clean finish. Place the gripper assemblies to the side of your work area.

Tip: To ensure a clean cut of the rubber padding, a small hobby cutter is the best tool.

¼” #4 Screws


3. Using (2) 3/8” #6 screws and lock nuts, install the HiTec HS475HB servo to the palm as shown in

figure 39. Do not tighten the #6 screws completely as this will be completed later in the construction process

Figure 39

3/8” #6 Screws

Palm

#6 Lock Nut


4. Using (2) ¼” #4 screws and lock nuts, install the servo pivot brace to the palm assembly as shown in figure 40. Ensure that the vertical slot of the palm aligns with the slot in the servo brace as shown in figure 40.

Figure 40

Servo Brace

#4 Lock Nuts

¼” #4 Screws

Assure Alignment


5. Using (2) #6 screws, lock washers and nuts, install a HiTec HS-475 servo to the servo pivot as shown in figure 41. (Note: Figure 41 depicts (4) #6 screws, lock washers and nuts. Only install (2) #6 screws diagonal from each other).

Warning! Failure to mount the servo on top of the servo pivot brace will result in the rest of the assembly not fitting together correctly

Figure 41

3/8” #6 Screws

#6 nuts

#6 lock washers


6. Using (2) #2 lock washers and nuts, install the servo arm to the pre-assembled 60-tooth gear and the servo gear brace as shown in figure 42. (Use the servo brace that has the slightly larger, offset, center hole in the middle of the 3 hole pattern). Repeat the exact assembly sequence for the opposite gear brace.

Figure 42

7. Install the servo gear brace assembly (The one with the larger, slightly offset center hole of the 3-hole pattern) to the palm servo as shown in figure 44. Ensure that the servo gear brace assembly can swing freely from the far, upper left corner of the palm to the point of the palm before securing it with the stock servo screw as illustrated in figure 44 and 44b..

#2 nuts

#2 lock washers

Servo Gear Brace

Gear

Servo arm

5/16” #2 Screws


Figure 43

Figure 44b


8. Using (1) 1” #4 screw, (2) washers, (1) lock nut and (1) ¼” nylon spacer, install the gear brace

assembly to the palm assembly as shown in figure 45. Ensure that the gear brace assembly is aligned (“in line”) with the opposite servo gear brace assembly (see figure 45b). Tighten the 1” #4 screw enough so that there is no “play” in the assembly yet loose enough to the assembly can be turned by hand.

Figure 44

Tip: Applying a small amount of grease between the washers and the aluminum parts of the gripper assembly will help to ensure smooth, friction free operation. Apply grease to the assemblies in figures 45 – 47 and 48 – 50.

1” #4 Screw

¼”#4 nylon spacer

#4 Washer

#4 nut

#4 Washers


Figure 45b

Note: Move the palm servo to the right to ensure that the gear trains engage fully and then tighten the palm servos (2) #6 screws .


Using (1) 3/8” #4 screw, (2) washers and (1) lock nut, install the gripper assemblies to the gear brace assemblies as shown in figure 46. Tighten the lock nut just enough so there is no play in the assembly but loose enough so the assembly can be moved by hand.

Figure 45

#4 lock nut

#4 Washers

3/8” #4 screw

Gripper assembly


9. Using (1) 1/2” #4 screw, (4) washers and (1) lock nut , install the flat braces as shown in figure 47. Once again, tighten the lock nut just enough so there is no play in the assembly but loose enough so the assembly can be moved by hand.

Figure 46

#4 Washers

#4 Lock Nut

1/2” #4 Screw

Flat Braces


Refer to figure 48 after this step is complete.

Figure 47


11. Using (1) 1” #4 screw, (2) washers, (2) ¼” nylon spacers and (1) lock nut, install the flat braces to the inside of the palm as shown in figure 49.

Note: The image below has been stripped of the prior assembly sequences for greater clarity.

Figure 48

#4 Lock Nut

1” #4 Screw

#4 Washers

¼” #4 Nylon Spacers


12. Perform the same assembly routine as outlined in the previous step for the opposite side of the gripper assembly as shown in figure 50.

Figure 49


13. Using (2) ¼” #4 screws and lock nuts, install the sensor bracket to the gripper assembly as shown in figure 51.

Figure 50

¼” #4 Screw

#4 Lock Nut

Sensor Bracket


• Refer to the next 6 images as a reference for the gripper assembly.

Figure 51


Figure 52


Figure 53


Figure 54 - Open gripper


Figure 55 - Closed Gripper

Note: If the gripper ends do not align as shown in figure 56, simply loosen the palm servo, slide the servo to the left to disengage the gear assembly and rotate one or both of the gear sets to align the gripper properly.


Figure 56


Chapter #8 – Installing the Gripper Assembly to the Forearm Assembly

1. Install (1) ¼” SAE Flat washer to the pem stud of the forearm assembly as shown in figure 58. Apply a small amount of lubricant over the entire surface of the outside of the washer. The flat part of the washer should be flush against the forearm.

Figure 57

¼” SAE Flat Washer


2. Remove the forearm brace and install the gripper assembly to the forearm assembly. Ensure that the gripper assembly can rotate freely at least 45 degrees in either direction from the straight position (level with the forearm) before securing the assembly with the stock servo screw as shown in figure 59.

Figure 58

3. Re-install the forearm servo brace.

Stock Servo Screw

Pem Stud

Forearm Brace


Chapter #9 – Retention Spring Installation and Servo Wire Routing

1. Adjust the lower arm brace so that it is 1” away from the servo pivot brace as shown in figure 60. Lay the arm assembly flat before measuring. DO NOT SKIP THIS STEP.

Figure 59

1” separation


2. Using (1) 1” #4 screw, (1) washer and (3) ¼” nylon spacers (2 are stacked on the top deck and 1 is

inserted between the upper decks), secure the long retention spring to the upper pivot table as shown in figure 61 and 62. Ensure that the retention spring is aligned with the bicep assembly before tightening.

Figure 60


3. Using (1) #4 5/8” screw, washer, lock washer, nut and ¼” nylon spacer, install the other end of the long retention spring to the lower arm brace as shown in figure 62. When tightening the screw, ensure that the spring coil is not twisted to the left or to the right of center of the screw.

Figure 61


4. Using (1) 5/16” #4 screw, washer and lock washer and nut, secure the small retention spring to the lower arm brace as shown in figure 63. When tightening the screw, ensure that the spring coil is not twisted to the left or to the right of center of the screw.

Figure 62


5. Route the servo wires through the hole in the upper and lower arm braces. Before securing the servo wires with the black tie wraps, ensure to rotate the arm joints through their normal movement to ensure wire clearance.

6. After the servo wires have been routed, use the (2) 12” servo wire extensions and the (1) 6” servo

wire extensions to ensure that the stock servo wires can reach the controlling electronics mounted on the board holder (figure 64).

Figure 63


Reference Pictures




SG5 Robotic Arm Safety and Operational Tips

ALWAYS secure the SG5 robotic arm to a solid platform before operating the unit (use the (3) pivot box tabs to secure the arm).

ALWAYS stay clear of the robotic arm when you are programming and operating the unit. A 3

foot diameter circle away from the arm is ideal.

When turning off the robotic arm, always ensure the arm is either held with your hand or that the arm is laying flat across the board holder first (via your program) before power is removed (see figure 65 ).

Ensure to program the SG5 using the program values found when you where aligning the biceps.

Failure to do so will result in shortened servo life of the shoulder servos.

Always use a 5v – 6v power pack. Using more voltage than the servo’s require on the SG5 can result in servo overheating and failure. Regulated 5V – 6V power is ideal for any robot using servos. A regulated 5v 6v power supply or a voltage regulator rated at 5v, 1.5 amps is ideal. CrustCrawler sells a 5v regulator pack and 6v, 2.5 amp regulated power supplies for the SG5 series of arms. Check our web site for details.

Figure 64


Samples Programs – SG5 Arm Test / SG5 Pickup and Place Check with our web site often to ensure you have the latest version of our code and to download the latest new code for our products.

Use the “SG5 Arm Test’ to ensure proper connections of the servos to the PSC controller.

'-------- [Sg5 Arm Test] ------------------------ ' {$STAMP BS2p} ' {$PBASIC 2.5} ' ' File........ SG5 Arm Test ' Purpose..... To test the arm after construction for basic ' movement of all joints to ensure ' proper connections of electronics and servos. ' Author...... CrustCrawler Inc. (Alex Dirks) ' E-mail...... [email protected] ' Web Site.... www.crustcrawler.com ' Started .... July 10 2004 ' Updated..... July 12 2004 ' When you connect your PSC controller to the arm servos, ' connect them in the following ' order: ' Ch0 is the rotating base servo ' Ch1 is the Left bicept servo ' Ch2 is the Right bicept servo ' Ch3 is the elbow servo ' Ch4 is the wrist servo ' Ch5 is the gripper servo ' ' --------------------------------------------------- ' ----- [ I/O Definitions ] ------------------------- Sdat CON 15 ' PSC Module connection to the Parallax BOE port 15 ' PSC servo channels Base CON 0 ' Rotating base LBicept CON 1 ' Left bicept RBicept CON 2 ' Right bicept Elbow CON 3 ' Elbow Wrist CON 4 ' Wrist Gripper CON 5 ' Gripper '----- [Adjustable Ramp Values] --------------------- ' Sets the ramp speed of the PSC controller (0 - 63). ' The higher the number the slower the movement ramp CON 11 '---- [Adjustable Baud Mode] ------------------------ baud CON 1021 ' BS2P24 baudmode (2400 baud, 8-bit, no parity) 'baud CON 396 ' BS2 baudmode (2400 baud, 8-bit, no parity) '---- [Servo Position Variables] ------------------


position0 VAR Word position1 VAR Word position2 VAR Word position3 VAR Word position4 VAR Word position5 VAR Word ' The basic range for the position ' variables are 400 - 1150 (+ Or -). ' Note: the parallal left and right bicept servos ' have a different value based On the values ' used to align the bicepts during construction. ' Subsitute the values that you used during ' the construction process. '---- [Home position] ---- ' Arm is in the upright position - gripper open position0 = 780 ' Base servo position1 = 750 ' Left bicept servo position2 = 735 ' Right bicept servo position3 = 620 ' elbow servo position4 = 750 ' wrist servo position5 = 1150 ' gripper servo '---- [Arm Adjustable Movements] ---- ' Un-comment each section below one at a time to observe ' different arm movements. ' You can change the servo position variables ' (400 to 1150) to obtain differnet arm positions. ' '---- [Arm goes down towards object] --------- 'position1 = 500 'Left bicept servo 'position2 = 485 'Right bicept servo 'position4 = 780 'wrist servo '---- [The gripper closes] ---- 'position5 = 810 'gripper servo '---- [The arm lifts back up with the object] ---- 'position1 = 750 'Left bicept servo 'position2 = 735 'Right bicept servo '---- [Rotates the arms base] ---- 'position0 = 980 'Base servo '---- [Puts the arm in the down position] ---- 'position1 = 500 'Left bicept servo 'position2 = 485 'Right bicept servo '---- [Opens the gripper] ---- 'position5 = 1150 'gripper servo '---- [Main Program] ------------------------------- SEROUT Sdat,baud,["!SC", Base, ramp, position0.LOWBYTE, position0.HIGHBYTE, CR] PAUSE 500 ' Give servo time to reach position SEROUT Sdat,baud,["!SC", LBicept, ramp, position1.LOWBYTE, position1.HIGHBYTE, CR]


SEROUT Sdat,baud,["!SC", RBicept, ramp, position2.LOWBYTE, position2.HIGHBYTE, CR] PAUSE 500 SEROUT Sdat,baud,["!SC", Elbow, ramp, position3.LOWBYTE, position3.HIGHBYTE, CR] PAUSE 500 SEROUT Sdat,baud,["!SC", Wrist, ramp, position4.LOWBYTE, position4.HIGHBYTE, CR] PAUSE 500 SEROUT Sdat,baud,["!SC", Gripper, ramp, position5.LOWBYTE, position5.HIGHBYTE, CR] PAUSE 500 END

SG5 Pickup and Place Routine

This routine picks up an empty pop can and places it 90 degrees to the right of the arm. You can build upon this routine easily simply by adding more movement positions to the existing table code. All values within the table are fully adjustable. Feel free to experiment! '------- [SG5 Arm Pickup and Place Routine] -------------------------- '{$STAMP BS2p} '{$PBASIC 2.5} '--------[Sg5 Arm Pickup and Place Routine] ------------------------ 'File........ SG5 Arm Pickup and Place Routine 'Purpose..... This completely adjustable program allows the SG5 arm to perform 'a simple "pickup" routine. The arm will reach out and down to an object (I used an 'empty soda can), pick it up, rotate to another position and place the can gently 'down. There is no "end" statement for this program, so the arm will repeat the 'operation. 'Author...... CrustCrawler Inc. (Alex Dirks) 'E-mail...... [email protected] 'Web Site.... www.crustcrawler.com 'Started .... July 31 2004 'Updated..... July 31 2004 '-------------------------------------------------------------------------------- 'When you connect your PSC controller to the arm servos, connect them in the 'following order: 'port 0 is the rotating base servo 'port 1 is the Left bicept servo 'port 2 is the Right bicept servo 'port 3 is the elbow servo 'port 4 is the wrist servo 'port 5 is the gripper servo ' '-------------------------------------------------------------------------------------- ' ----- [ I/O Definitions ] ------------------------- PSC CON 4 ' PSC Module ' PSC servo channels Base CON 0 ' Rotating base


LBicept CON 1 ' Left bicept RBicept CON 2 ' Right bicept Elbow CON 3 ' Elbow Wrist CON 4 ' Wrist Gripper CON 5 ' Gripper '---- [Adjustable Baud Mode] ------------------------ Baud CON 1021 ' BS2P24 baudmode (2400 baud, 8-bit, no parity) 'Baud CON 396 ' BS2 baudmode (2400 baud, 8-bit, no parity) '---- [Movement Variables] ------------------------------------------------ servoAddr VAR Byte ' Servo addresses Index VAR Word ' Pointer variable servoPosition VAR Word ' Servo Position ramp VAR Byte ' Ramp used in SEROUT biceptLoop VAR Bit delay VAR Word '---- [Servo Address and Position EEPROM data] ----------------- 'The data table below represents different servo addresses and actual positions 'of the servos in the BS2P24's EEPROM. In line one for example, $00 is the rotating 'base servo and "Word 800" represents the servo position which can vary from 'approximately 400 - 1150. The data in the table below is executed in 'sequencial order (one complete row before going to the next row.) The beauty of 'having your servo and position data in a table is that it allows for easy servo 'selection and fully adjustable movement. Additional routines can be added 'to the table to perform an unlimited amount customized arm movement routines. Test DATA $00,Word 800, $01,Word 650, $02,Word 635, $03,Word 760, $04,Word 850, $05,Word 1150, $01,Word 450, $02,Word 435, $05,Word 980, $01,Word 650, $02,Word 635,$00, Word 1150, $01,Word 450, $02,Word 435, $05,Word 1150, $01,Word 650, $02,Word 635, $00, Word 800, $FF '---- [End EEPROM Data] ---------------------------------------- ' LBicept and RBicept servos make up the arm's ' bicept. Both servos must move at the same time ' or one of the servos will add stress to the other. ' This bit variable causes the ' Send_EEPROM_Info_to_PSC subroutine to grab ' 6 bytes from EEPROM instead of the normal ' 3 bytes. This is accomplished with a ' Do... Loop While biceptLoop < 1 biceptLoop = 0 delay = 1500 '-----[ Main Walking Routine ]------------------------------------------ EEPROM_Reader: ' Assign EEPROM starting address Index = Test ' Read PSC servo address at Index and assign ' ramp to each PSC servo position. Each servo's ramp ' can be adjusted to any speed. Pause statements are used to delay the ' arm movement while the gripper is either closing or opening. READ Index,ServoAddr


DO WHILE servoAddr <> $FF SELECT servoAddr CASE Base ramp = $a delay = 1500 CASE LBicept ramp = $b delay = 1500 biceptLoop = 1 CASE Elbow ramp = $a 'delay = 1500 CASE Wrist ramp = $B 'delay = 1500 CASE Gripper ramp = $b 'delay = 1500 ENDSELECT GOSUB Send_EEPROM_Info_to_PSC LOOP 'end GOTO EEPROM_Reader '----- [Serial Out EEPROM values to PSC] ------------------------------- 'This is the main "engine" of the program. The data from the table and the 'pause and ramp routines are used in the SEROUT code below. Send_EEPROM_Info_to_PSC: Move_Bicept: READ Index, servoAddr,servoPosition.LOWBYTE,servoPosition.HIGHBYTE SEROUT PSC,Baud,["!SC",ServoAddr,ramp,servoPosition.LOWBYTE,servoPosition.HIGHBYTE,CR] 'DEBUG HEX ?servoAddr, HEX ?servoPosition.LOWBYTE, HEX ?servoPosition.HIGHBYTE Index = Index + 3 IF biceptLoop = 1 THEN biceptLoop = 0 'DEBUG "Bicept found",CR GOTO Move_Bicept ENDIF READ Index,servoAddr PAUSE delay RETURN

Documents

SG5-UT Robotic Arm - CrustCrawler · PDF fileSG5-UT Robotic Arm ... Constructing the Gripper Assembly ... • Remove the aluminum body parts from their protective bags and lay them