UPDATE March 24, 2016: Since this was written we have switched from continuing rotation servos to DC motors and modified the body accordingly. The experience and advice for working with laser-cut plywood is still the same. We continue to be pleased with wood robot bodies.
The lessons 1 through 18 incorporate a rolling robot. We chose this as a platform for exploring sounds, infrared, remote control, and messages. The body is one of our design because commercial robot bodies of good quality are expensive and difficult for students to modify. Besides, we like to minimize costs in order to allow students to take their work home with them. The example shown here is configured to detect and respond to obstacles and to be controlled with an infrared remote. The RED LED is to indicate power is on, a useful feature for when the robot is not moving.
The instructions for assembling the body are in the How-to section of this site. This example is also using our Motor Controller Shield. Velcro is used to hold the battery pack on the back. Some students place the batteries underneath.
Our design is intended for fabrication from 1/10" bamboo plywood. The reason for plywood is the material is attractive and easy to work with. We've had students adapt the basic body to a number of interesting and occasionally weird devices. The reason for bamboo is we wanted a material that was renewable.
This little robot body has proven very useful. One day soon we will be posting plans for a DIY Radio Remote Control. This little gadget has been used to control a model airplane, and does quite well. But it was tested and debugged using one of these rolling robots. The prototyping area of the motor controller hosted the electronics of the receiver.
We've also had students modify the design to make robots that are powered by VEX motors, robots configured for battle, and once even a robot that played patriotic music while waving a flag. It's a sturdy little design that begs to be adapted.
Until recently we did not have a laser cutter of our own. All fabrication was performed by Ponoko. With this posting I have placed the Adobe Illustrator file we use when an order is sent to Ponoko (Adobe Illustrator Robot Chassis File). The file is for fabrication of almost eight robot bodies. But it is short one front panel of a complete set of eight, alas. Try as we might we couldn't find room for that last panel. Maybe someone else can do it. The lines are carefully shared to minimize cutting time, and therefore costs.
We don't believe any licensing rights are involved. The body is simply a box with holes cut into it, and the three wheel design has been around as long as tricycles.
One last thing - we've tried many different glues and even the use of glue blocks for strength. The best results seem to come with using corner clamps to hold joints tight while glue dries and the use of Testor's model Wood Cement. Elmer's Wood Glue also works well but has a long drying/curing time.