Building the My First Robot Chassis

RBB-Bot: Operating the RBB-Bot

Previous: Assembling the Motors and Wheels

Don't insert any batteries just yet.

Test the operation of the RBB-Bot by putting it on the floor, motor-side up.

Review your handiwork to check for accidental shorts, bad soldering joints, or other problems. When you are satisfied all looks good, insert three AA batteries (standard alkaline or rechargeable) into the battery holder. Place the RBB-Bot base on a small book to lift its wheels from the ground, then try each of the control switches. The motors should turn as you flip the switches.

With the control panel in your hands, press both switches forward. The robot should move forward. ("Forward" and "backward" are arbitrary on the RBB-Bot, but for out purposes here, the back of the base is the end with the skid.)

If instead:

  • The robot moves backward, loosen the nuts on the switches, and rotate both 180 degrees. Retighten the switch nuts.
  • The robot turns in a circle, loosen the nut on the switch controlling the motor that's going in the wrong direction. Rotate the switch 180 degrees, then retighten the nut.
  • The right and left switches control the wrong motor, flip the control panel around. Or, remove both switches, reverse their position on the panel, and put them back in.

Place the RBB-Bot in the center of the room. Practice steering the robot around the floor. You'll note that tight, spinning turns are performed by pulling back one switch while the other is pushed forward. A slower "pivoting" turn is accomplished by releasing one of the switches (depowering its motor), and letting the other motor continue.

Have your RBB-Bot move toward a corner in the room, then see what kinds of motor control actions are needed to reverse its direction so it doesn't get trapped. The techniques you discover here are the same ones you'll use when the RBB-Bot is under automated electronic control, which is covered in upcoming installments of this series.

RBB-Bot Phase 2: Electronic Control

So now you've been introduced to the RBB-Bot. If you've followed along, you've constructed your bot, wired everything together, and tried it out in front of the family cat.

You're now ready to move to Phase 2, which is converting the entry-level RBB-Bot from manual switch control to electronic control. In the next part of this series, you'll discover how to use rudimentary circuitry to give your RBB-Bot the sense of touch. It'll detect obstacles, even your friendly feline, and automatically steer around whatever doesn't get out of its way.