I absolutely love Lego. As you might have noticed from the last time I found a Lego project that involved a little creative engineering, these Lego/electronics mashups always make me happy. Here is another vehicle-related project that puts these simple blocks to use. This project adds radio control to a Lego car. However, unlike the last project I profiled, this one uses Raspberry Pi to open up many more options and features.
Karl Herrick, with the help of his kids, started by assembling a 4x4 Lego Crawler. This one uses the more advanced Technic style blocks instead of the basic blocks, but it still has a simple IR interface for control. Herrick used a Raspberry Pi to control the car, instead of controlling it directly.
For control, Herrick built a mechanical solution. He is literally moving the joysticks on the remote with a servo, as opposed to issuing IR commands from the Raspberry Pi. As you can see in the video above, he has a webcam attached to the Raspberry Pi, allowing him to drive it with a first-person perspective. His cat may or may not be very amused by this.
If you'd like to see how to wire this up, or if you want the code to replicate this on your own, you can find that on Herrick's blog.