BOBB3E is one of the supplemental robot projects from Lego’s Mindstorms EV3 Robotics kit (kit # 31313). Easily downloadable through the Mindstorms program interface for your PC or Mac, this pint-sized forklift packs plenty of punch in both entertainment value and building up your skills for your own robot designs. Like TRACK3R , BOBB3E uses a caterpillar track system of movement that I prefer for stability and ease of control. Additionally, the use of the medium motor for the lifting and lowering of the fork arms provides plenty of power to lift some fairly impressive weights. Digging a little deeper, here are some amazing lessons that BOBB3E can teach us:
Use of Gears
Gear use is one of those skills that will always come in handy in a Mindstorms EV3 project. BOBB3E is no exception with the clever use of gears in conjunction with the medium motor to make up the mechanism that controls the lifting/lowering of the forks. Although not terribly complex, the 36-tooth gear is used together with the 12-tooth beveled gear to create the device. Additionally, the 20-tooth gear and the 12-tooth gear make up the motion mechanics of the tank tracks using the large motors as their source of power. Getting familiar with some of the more basic uses of gears will prepare you for more complex applications such as those used with the GRIPP3R robot.
The Switch Loop
One of the great strengths of the Mindstorms EV3 kit is the ability to program your creations to do whatever you want. BOBB3E comes with a fully functional program that you can use as soon as you are done constructing the robot. The heart of this program is the adept use of the switch loop together with the EV3 IR (Infrared) remote control. The switch loop allows the programmer to build in actions to perform given a set of conditions, or ‘cases’, to the input being received. For example, one of the ‘cases’ that BOBB3E might encounter is what to do when both the top red and top blue buttons on the IR remote control are pressed. In this situation a programming sequence takes over that rotates both large motors forward, which in turn moves BOBB3E forward. The great versatility of the switch loop is that a specific case and associated action can be built around every conceivable situation that BOBB3E might encounter.
BOBB3E also comes with the ability for its programming to be modified, which gives you the opportunity to complete various challenges or missions. Anything from minor modifications such as adding sounds during actions or manipulating the motor strength to larger scale redesign such as adding the ability for different IR remote control channels to be used can be made to the original program. This provides a great way to experiment and learn more about how to work in the program design space without worrying about losing anything critical.