A tracked vehicle makes a great platform for testing sensors, motor drivers, micro-controllers and softwware. A small chasis, like the Tamiya chasis kit can provide a proving ground for your project before you go full scale.
The chasis kit is an easy way to get started, but does have some draw backs. The motor and gearbox you get with the kit has a solid axle, so there is no way to independently control the left and right tracks. To do this you willneed the dual gearbox. The chasis is also narrow, leaving little room for electronics. For these reasons I would recommend buying the tread kit and making your own chasis.
The chasis kit is an easy way to get started, but does have some draw backs. The motor and gearbox you get with the kit has a solid axle, so there is no way to independently control the left and right tracks. To do this you willneed the dual gearbox. The chasis is also narrow, leaving little room for electronics. For these reasons I would recommend buying the tread kit and making your own chasis.
 |  |
Above you can see one of the Tamiya dual gearbox assemblies. This one has four possible gear ratios. In the photo below, you can see I have used a simpler dual gearbox. This one is slightly smaller, but still gives you two gear ratio options. I designed a chasis that gave me a tread pattern, ground clearance and platform size advantage over the standard chasis kit. I found 3mm bolts worked fine for the axles, allowing improved groung clearance over the standard through axles.
 |  | Once you have a rolling chasis with a drive train it's time to get creative and decide what components to load up your chasis with. Ive used Arduino and RaspberryPi boards as my controller paired with motion sensors, ultra sonic distance sensors, light sensors etc. Ive also had success controlling the device wirelessly using both bluetooth and wifi modules. |
Once you've decided what components willbe on your vehicle, its time to select a power source. wether you keepit simple with AA and 9 volt batteries or youtry to save some space and weight by using a rechargable lipo battery with a voltage regulator, you will need to pay attention to the different voltage and amperage limitations of each of your chosen components. For example, your motors can likely handle 6 volts or more, but a raspi should only be supplied with 5 vdc.
