Quantity   Component name
1 × DC-DC converter A variable output DC-DC converter lets you use a wide range of power supplies
1 × battery Evaluation, Demonstration Kits, Boards and Modules / Evaluation Kits, Boards and Modules
1 × Beaglebone Black
1 × Office chair wheel
2 × Circular supports More wheels
8 × 1cm diameter steel bolts + 3 nuts for each get some spares
4 × Towerpro plastic gear servos The 2$ ones are fine. You only need 2, but buy 4.
2 × Towerpro metal gear servo For steering. You only need 1, but buy 2.
1 × USB to serial converter Linux compatible
1 × Light switch box Makes a good case for the beaglebone black
1 × USB hub To add more usb devices
1 × double sided tape or velcro tape For when you're not where something should go
1 × 2 part epoxy glue You'll need a lot
1 × 2 Large pieces copper clad circuit board For the chassis. You can use perfboard, carbon fiber, rigid plastic, or even wood.
1 × ATMega16 (servomotor controller) Microprocessors, Microcontrollers, DSPs / ARM, RISC-Based Microcontrollers
1 × 20Mhz crystal (servomotor controller)
1 × MAX232(servomotor controller)
4 × 1uF capacitor (servomotor controller)
1 × 220uF capacitor (servomotor controller)
1 × RS-232 connector (servomotor controller) Whatever the opposite type of your usb-to serial adaptor is