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To build this robot toy car, you will need:
Components:
* an RC car (67RMB, http://item.taobao.com/item.htm?id=7905841099)
* an additional battery (to the one that comes with the RC car) rechargeable Ni-Cd 400mAh/6V battery pack
* an Arduino (any should do, we use the Dueminalove)
* a pile of cables with pins
* one or more ranging sensor of some kind (infrared such as Sharp IR or Ultrasonic such as the Parallax Ping or both)
* a small breadboard
* an IC with at least 4 transistors (such as the ULN2803APG) or 4 separate NPN transistors
* two AA battery (to test the RF transmitter)
Tools:
* a USB cable (standard USB transfer cable)
* a PC (Mac, Linux or Windows)
* Arduino software
* a Dremel (or its Chinese copy equivalent...)
* a wire stripper
* a marker (Sharpie fine point permanent marker)
* a right angle ruler
* a set of precision screwdrivers
* some electric tape (or alternatively, little name stickers...)
* four plastic bags for the screws you'll remove
* a soldering iron
* a ballpen
* cardboard box at least 15cm X 25cm (surface to put the woodboard on top to drill holes)
* a camera for posterity!
Optional
* possibly a small servo-motor to rotate ranging sensor
Steps:
Charge your batteries
* move to the next few steps that don't require battery while you wait (4 hours charge time)
Remove the plastic shell from the top of the car
* Turn over and start unscrewing starting with the back of the car
* Note that you may have to unscrew at an angle to get the screws furthest back out
* Keep the screws securely in a bag, organized by step (write down where they came from with the marker)
* You will find 4 screws on the main plate, 2 in front, 2 for the lights
* Get the antenna out of the shell (don't pull out too quickly - watch out for those thin wires connecting to the light)
* Put the shell on the side
* Remove the hot glue by melting it with soldering iron and a pair of tweezers
* Remove the useless soundbox plastic cover box on top of the servo (3 screws)
* Screw the lights upside-down on the servo plastic box now available holes
* Tape the electric wires from the light to the plastic chassis
Test your car with the provided RF remote to verify that it does indeed still work
Take apart the remote
* twist the round plastic piece securing the antenna
* remove screws to open the case (6 screws)
* remove the screws holding down the board
* take care to mark which wire goes to source and ground (ex: the wire to positive marked the marker)
* unscrew the antenna
Create a new wood plate by tracing the various components and holes (don't forget the hole for the antenna)
* Dimension: 15cm wide by 25cm long (size of wood board is chosen to fit the board within the wheels)
* Use the right angle ruler: create an angle, measure desired width and height, trace box with marker
Remove the plastic plate on which the plastic shell was screwed
* Remove the four screws and then squeeze the hinges on the front of the plate to remove
Do the layout
* Figure out where to put the holes by overlaying the plastic plate on the board
* To locate holes, remove the ballpoint from the pen body
* Take all the electric components and place them on the new plate until satisfied with the layout
* Trace screwholes and the outline of parts for electronics
* Don't forget to leave a larger hole on the front of the plastic plate and to the left for the antenna to come out!
* Create a grid of holes in front and in the back of the board to give you flexibility in placing the sensors
Cut the wood plate with the dremel
* Cut rectangle with the Dremel and than break if off
* Sand edges of rectangle
Drill holes into the wood plate with the dremel
* use a spare piece of wood or cardboard box upside-down
* put the wood board on the cardboard box
* drill holes!
* Verify alignment with plastic plate of chassis
* Test alignment with antenna
Assemble mechanical parts
* Put back the plastic plate on the car
* Tie-wrap the wood board to the plastic plate
* Tie-wrap the components to the wood board
Assemble electronics
* Connect wires to/from the various components (except the battery)
* Strip the wire from the transmitter and push the wire filaments in the breadboard using the wires with pin
* If possible, use consistent wires (white or yellow for signal, black or blue for ground, red or orange for power)
Place the sensor(s)
* Make sure the sensors are physically secure (they tend to move when the robot hit something...)
Write basic Arduino program
* Start Arduino IDE
* Write basic Arduino program
* Connect to USB
* Upload
Test your robot
* transmitter light comes on
* sensor obstacle detection works
* Test that motor control works
* Turn on the car, manually trigger the sensor
* Put it on the ground and let it fly! (don't forget to get it on video!)
Next step
* Use version control (github.com or code.google.com) to keep source and documentation
* When a version (kinda) does something interesting, commit to source control and explain observed behavior
Future
* Mount electronic parts on motherboard stands (?)
* Create a working RF transmitter that can talk to the receiver
* Design and get PCB done (integrating power connection, switches, etc)
* Design and get aluminium plate done