This is an old project from back in 2001 or so. It is my attempt at a SHRIMP rover. This robot chassis adapts passively to the surface it is driving over. It can climb over many obstacles, including books, a pillow and even stairs! It is really an amazing piece of work, and is very simple to build.

Each wheel is driven by its own motor, so you will need six motors in total to build this chassis. The rear motor is fixed permanently to the chassis body, and the remaining five motors are on pivoting legs.

As you can see, the motor is directly connected to the drive axle via a worm gear. The worm gear provides both torque and hold for the wheel. If the motor stops rotating, the wheel is locked in place. Thus the robot can hold itself in place on an oddly shaped obstacle.

Each side of the chassis has a pair of wheels mounted on legs. The legs are connected by two cross bars and pivot at two points. The crossbars are themselves connected to the chassis at two points. Thus the leg pair can ride up and over an obstacle independently of the main chassis body.

The front wheel is connected to the body but can pivot at both the body connection and at the leg. The front wheel can ride up and over an obstacle while the body trails behind. It then pulls the chassis over the obstacle allowing the side wheels to drive. The rear wheel is permanently engaged and drives the chassis over an object.

Pictures