Some three years ago, my colleague and I built a car which consisted of a Lego chassis, and a color QuickCam. It was a good idea and broke new ground because of its tilt-and rotate features but ultimately slow and could not drive on much more than a wood floor. Thrilling as it was, we wanted more out of it. It lacked the performance necessary to do real exploring. (The world isn't flat after all, and neither are the other planets.) By this time, Patrick already had a high-performance off-road R/C car. R/C stands for Remote Control. This means the vehicle can operate without being physically connected to a control unit. Instead, it uses radio waves. By now, my other colleague, Moris Behar took an interest in the project to create a better explorer using my R/C car. The problem was how to include all of the other bells and whistles of the previous car.

After a month or so of hard after-school labor, our new explorer was born. As mentioned before everything sits on my R/C car. This enables it to travel fast, and have all the power it needs to climb hills, and deal with all sorts of debris in it's path. Next, we mounted our newest investment: a gray scale pinhole camera. This is a very small, but high resolution camera. The entire thing is about half the size of a credit card, and weighs about the same. This we attached to our own Lego chassis on top of the car. The camera was mounted to a rotating "swing" which allowed the camera to tilt up and down.

From here, we decided to make our invention even better. The off-road car part with the tilt camera was good, but it still lacked something... A view! Normally, the camera would only be able to see at ground level. This makes it difficult to see the road hazards ahead. The answer would be to have the camera elevate it's position. To do this, we engineered what looks to be a crane boom onto the car. It consists of an arm about the length of the car, which can be raised perpendicular to the ground. From this position, the camera can still tilt, and the car can still drive without concern for it flipping over. The biggest problem with the elevating arm was getting the power to move it up. A regular motor would need an immense amount of gear reduction to move it. The answer to our problem was pneumatics. Pneumatics are relatives of hydraulics which are seen on many construction vehicles that make the "joints" move. Instead of using oil in hydraulics, pneumatics use air pressure.

Our car has two pneumatic rams with an on board compressor. A motorized valve regulates the amount of air allowed into each ram. This way we have quick power to elevate the arm, and a controlled decent back to ground level.

All of the Lego motors are once again powered through the Lego Dacta Control Lab. This means, that there are user-friendly on screen controls (which we programmed) to control the Lego parts of the roamer. Every part of the Lego chassis (camera, pneumatics) can be controlled on screen. We even made a program that allows a user to program various features of the car without knowing anything about the logo language. (We strive for simplicity.) The more advanced features include direct keyboard controls (much like a game) for the serious user.

The only setback to this entire project, is that the car must drag about 50 feet of ethernet cable behind it. This makes it possible to control the motors. There are just so many functions that this car does, it would be difficult and costly to make the car truly wireless.

Patrick Mahaney is a student at the High School For Environmental Studies in New York City. He has designed and built many projects for his school as well as in his free time. He has presented his work at Parent-Teacher Conferences, the Museum of Natural History in New York City, and twice at the UFT "Kid Connections" Conference. He has also written an article for "Logo Exchange", in the summer 1997. His most recent appearance was at the Logosium '99 convention in Philadelphia.

* This article appeared in the Fall 1999 issue of Logo Exchange Volume 18, Number 1