Introduction: Simple Bots: Wobbler
Typically, you learn how to wobble before you learn how to walk. But in the world of bots, anything is possible! That is why a day after showing you how to walk and two after showing you how I roll, I am back to show you how to do a little wobble wobble. That's right! In almost no time, you can be out wobbling around with the best of 'em. All of the parts in this project are simple to find and even less-than-experienced bot builders should be able to make this one pretty easily. And, more experienced bot builders should be able to have some fun modding this one, as the casing leaves a lot of room for experimentation.
Want to watch me build this project from start to finish? Check out this webinar I led on June 13th 2017 to see me complete the whole build!
Step 1: Go Get Stuff
You will need:
(x2) continuous rotation servo motors with the controller removed**
(x2) self-adhesive oval coat hooks
(x1) small plastic container
(x4) zip ties
(x1) 4 x AA battery holder
(x4) AA batteries
**To learn how to remove a servo controller, visit this page.
Step 2: Remove the Horns
Remove the servo horns from the motors.
(The servo horns are the gear-like objects attached to the motor shafts.)
Step 3: Insert
Place the servos inside the plastic container such that they are mirrored back to back. The servo shafts should be located near the bottom of the plastic container and off-center.
Step 4: Mark
Mark the plastic container with a dry erase marker to indicate the position of the motor shafts and the servo mounting holes.
Step 5: Drill
Drill holes in the plastic container where you have just made the dry eraser marks in the previous step.
For the smaller mounting holes, an 1/8" drill bit should be suitable. For the motor shaft, I recommend using either a 3/8" or 1/2" drill bit.
Step 6: Mount the Motors
Position the motors inside the case and zip tie them securely in place.
Step 7: Wire It Up
Twist together a red wire from one of the motors with a black wire from the other motor, and either wire from the battery holder.
Next, twist together the remaining three wires to form another pair.
You can solder them for a more permanent bond, if you wish.
Step 8: Close It Up
Place the battery holder inside the case.
Close the case and reattach the servo horns.
Step 9: Wheels
Take the coat hooks and trim off the hook part with diagonal cutting pliers or a small saw.
You should now be left with self-adhesive oval wheels.
Step 10: Attach Wheels
Peel off the adhesive backing and secure the wheels to the servo horn such that the horn is completely hidden behind the wheel and the wheel is very off-centered from the axis of rotation.
Step 11: Power It Up
Remove the lid, insert batteries, replace the lid and let it go.
Experiment with putting the bot on different sides to observe all of the ways it moves.