Build Your Own Robot

Learn how to create a robot like the ones in the "Robotic Exploration of the Next Frontier" booth at the USA Science and Engineering Festival 2016

ExplorationRobot-blowout

Robot Assembly Instructions

Thank you for visiting our booth during the 2016 USA Science and Engineering Festival. Our team put together comprehensive instructions on how you can build the same robot you controlled at the show.  

Disclaimer

Please note that while we have designed this as a robot that kids can use to experiment with, assembling the robot does require the use of power tools, soldering irons and other potentially dangerous tools. Adult supervision or intervention is HIGHLY recommended. Lockheed Martin provides these instructions for educational purposes only and takes no responsibility for any injuries or damages suffered.

Parts List

Note, these are where we purchased the parts, but they may be found elsewhere. The links are not meant to be an endorsement of the suppliers. The robot chassis we used for the activity has been discontinued, so the chassis listed below are similar, but not exactly the same, as the ones used at the USA Science and Engineering Festival.  

Robot Chassis  

http://www.robotshop.com/en/iron-man-4-indoor-tracked-chassis.html

or

http://www.robotshop.com/en/iron-man-5-indoor-tracked-chassis-arduino.html

Raspberry Pi Model B v2 (or 3)

https://www.adafruit.com/products/2358

or

https://www.adafruit.com/products/3055

RasPi Robot v3 by MonkMakes

https://www.adafruit.com/products/1940

 

Raspberry Pi Camera

https://www.adafruit.com/products/1367

 

Ultrasonic Range Finder

http://www.robotshop.com/en/hc-sr04-ultrasonic-range-finder.html

 

M3 standoffs (x2 packs)

http://www.amazon.com/sets-hexagonal-standoffs-mounting-kit/dp/B00C0Q51L0/ref=sr_1_5?s=electronics&ie=UTF8&qid=1461098922&sr=1-5&keywords=M3+standoff

 

(Note, you’ll need 2 packs of these 12 standoffs total, and will need to find different screws as the heads on the included ones are too big. We found them at ACE Hardware in their special screw/bolt section. M3-10, 6mm non-flanged head.)

USB Wifi Adaptor

(Note, not needed if you use Raspi model B v3 as the V3 has Wifi built in.)

 

http://www.amazon.com/Panda-150Mbps-Wireless-Adapter-Antenna/dp/B004AC0L4Y/ref=sr_1_1?s=electronics&ie=UTF8&qid=1461099965&sr=1-1&keywords=Panda+Raspberry+Pi+Wifi+Adaptor

 

Battery Pack

Either:  (Basic users)

http://www.amazon.com/Battery-batteries-connectors-installation-270-0407/dp/B007Z843QC/ref=sr_1_7?s=electronics&ie=UTF8&qid=1461100059&sr=1-7&keywords=8+AA+battery+holder

 

or (Advanced users)

 

http://www.horizonhobby.com/xt-60-connector-set--35mm-%282%29-dync0140

and

http://www.venompower.com/collections/venom-drone-batteries/products/venom-15c-3s-2200mah-11-1v-lipo-drone-battery-with-universal-2-0-plug

 

 

Note that the advanced option will run much longer on a single recharge but is recommended only for people with prior RC model car LiPo battery experience, and requires a LiPo battery charger unit, not listed.

Micro SD Memory Card

Note, we do not list a specific card – Just get something that is microSD, class 10, and 8GB (or larger) in size.

Other Tools and Materials Needed:

  • Sticky back Velcro®
  • Electrical tape
  • Long metal twist ties (like from loafs of bread)
  • 22-24 gauge braided wire (can use solid core, but braided is easier to work with as it’s more flexible)
  • Soldering iron
  • Wire stripper
  • Small screwdrivers (both flat + Phillips head)
  • Small adjustable wrench
  • Drill with bits
  • Pen/marker with fine tip

Assembly Instructions:

  1. Remove the Raspberry Pi® computer from the packaging and place it on top of the blue robot chassis metal plate such that the USB + Ethernet connectors are to the rear of the robot chassis (the end that doesn’t have the part that sticks down). Position the Rasperry Pi computer so the front of the board is about 1” back from the front of the robot and centered left/right. Use the marker to mark where the holes are such that the marks transfer to the chassis plate. Then set the Raspberry Pi board aside.
  2. Use a small drill bit and drill holes in the chassis plate where you made the marks.
  3. Take one of the brass standoffs and push the threaded male end through the hole so it is sticking out the bottom of the chassis plate. Attach and tighten one of the small nuts onto the bottom to hold the standoff in place. Repeat for all 4 holes.
  4. Attach 2 additional standoffs on top of each of the 4 standoffs that you installed in step 3, to create towers 3 spacers high.
  5. Using 2 of the small silver Philips head screws that came in the chassis kit for each motor, install the motors into the chassis so that the motor has the wheel hub sticking through the front wheel holes in the chassis. Repeat for the other motor.
  6. Line up and press on the front wheels to the motor hubs (use the wheels with the tiny holes in the middle).
  7. Using the tiny long black Phillips head screws, screw in the front wheels.
  8. Assemble the 2 tank treads such that there are 20 segments in each tread and they form a loop. 
    1. Note, in some cases you might be short the tread pins. If this happens, you can cut and use a thicker paper clip bent on both ends to substitute.
  9. Loop one of the treads around one of the front wheels. Place one of the back wheels inside the tread and line it up with the rear hole.
  10. From the outside, push a thick axle bolt through the wheel and chassis. Secure on the inside of the chassis using a washer and then one of the nylon nuts. Do not overtighten!  Just get it snug enough that wheel doesn’t wobble, but loose enough that the axle bolt and nut can turn freely.
  11. Repeat steps 9+10 for the other side.
  12. Line up the Raspberry Pi board on top of the spacers. Screw them in using the small M3 screws. NOTE: Make sure the screw heads are not making contact with any electrical components on the Raspberry Pi board! If they are you need to find screws with smaller heads.
    1. DO NOT use a drill as you are likely to crack the Raspberry Pi board.
    2. DO NOT force the screws through the board.
    3. If the screws won't fit through the holes on the Raspberry Pi board (ours didn't), take a drill bit slightly thicker than the shaft of the screw and manually and gently turn it through the holes of the Raspberry Pi board to open the holes up a bit more.
  13. Set the chassis aside.
  14. Wrap electrical tape around the back of both the Raspberry Pi camera board, as well as the ultrasonic range finder unit such that there are no electronic pieces exposed.
  15. Push the ultrasonic range finder through the holes in the 3D printed bracket such that the connection pins are facing upwards.
  16. Take 2 twist ties and strip any coating off them so that only the bare metal wire remains. Slide one through each pair of holes in the front of the sensor bracket and through the holes in the ultrasonic sensor such that the ends of the twist ties are sticking through the back of the sensor. Twist the wires so they form a snug fit against the electrical tape on the back of the sensor. Do NOT let the wires directly touch any electrical components! Repeat this on the other side. This should hold the ultrasonic detector in place on the bracket.
  17. Position the Raspberry Pi camera through the top opening in the bracket with the ribbon cable coming out of the top.
  18. Similar to step 16, do the same for the Raspberry Pi camera to hold the camera to the sensor bracket.
  19. Position the sensor bracket onto the front of the robot. If it is positioned properly, the 2 holes in the front bottom of the bracket should line up with 2 small holes on the front of the robot. Using the same technique as in steps 16+18, use twist ties to link the bracket to the robot chassis. Additionally on the back of the bracket, there are 2 other holes that should line up with a pair on the top of the chassis in front of the rectangular hole on the chassis. Again, use another twist tie. If you tighten both of these twist ties, the bracket should be held in place tightly and shouldn’t wobble.
  20. Cut 4 wires approximately 6” long each, and strip the casing off 1/8” on each end.
  21. Place one stripped end of wire through the small eyelet of the motor and solder it into place. 
    1. Warning- the motors have VERY fragile tabs. Do NOT use too much solder and do not keep the iron in contact with the tab for very long or you could break it.
  22. Repeat with the other 3 wires such that there is a wire attached to each tab – 2 per motor. Feed the other end of the 4 wires through the rectangular hole on the chassis.
  23. Gently lift the little latch on the Raspberry Pi computer that sits between the audio jack and the HDMI port. It will only move up slightly. Once unlatched, gently slide the free end of the camera ribbon cable into the slot between the latch and the rest of the bracket such that the blue backing on the ribbon cable is facing the Ethernet port at the rear of the robot. Once inserted, gently close the latch.
  24. Take the RasPi Robot V3 board and line up the socket on the bottom such that the front of the board (where all the green screw terminals are) is lined up with the front most pins on the Raspberry Pi computer’s GPIO pins. Be sure both rows are lined up and then gently press down to attach the board to the Raspberry Pi computer.
  25. Tuck the Camera ribbon cable under the free side of the RasPi Robot board.
  26. Unscrew the 6 green terminal screws on the RasPi Robot board on the side closest to the HDMI port.
  27. Following the labels on the board, insert the 2 wires for the left motor into the 2 screw terminals labeled L and tighten each terminal. Repeat for the Right motors into the R terminals.
    1. (Note, if you operate your robot and the motors seem to spin the wrong way, you need to swap the motor wires on that motor to the screw terminals they are in.)
  28. Take the battery connector wire and insert the red wire into the +V terminal and the black wire into the GND terminal. Tighten the screws.
  29. Insert USB Wifi adaptor (if using a Raspberry Pi 2 computer. If using a Raspberry Pi 3 computer you can skip this step as the model 3 has Wifi built in.)
  30. Finally slide the battery pack in under the Raspberry Pi computer, between the standoffs (we used Velcro® to help hold them in place), and connect the battery pack to the battery terminal.

Software Instructions

Link to our software instruction at https://github.com/joemirizio/mars-explorer.

For More Information