Let's build circuit for the robot.
Build the circuit shown in picture 1. If you want to design your own Snap Circuits diagrams go to http://www.snapcircuits.net/learning_center/designer
See the photographs for the step by step build.
You'll recognize the power regulator block (B5), the PICAXE (U14), the H-bridge block (U8, labeled "Motor Control"), and the snaps for the rear of the rover. You'll also notice some new components. In addition to the snap conductors and the jumper wires, you will notice 4 1K ohm resistors.