~~~~~~~~~~~~~~~~~~~~~~~~
DESCRIPTION
~~~~~~~~~~~~~~~~~~~~~~~~
VIDEO HERE
My crawler is more aptly named a Roller. From one of my first crawler attempts in lab last week, where I attached the servo inside my roll of tape, I could see that there was potential for harnessing the weight of the servo itself and the kinetic energy of the rolling back and forth. I initially tried various lever lengths to see if I could simply push halfway around the circle until the weight of the servo crested the peak and it’s own weight would pull it back down to complete the full rotation. I never quite succeeded and was still faced with the need to move the servo lever back the other way without losing the ground I had already gained. I switched my approach to try making a kind of ratchet gear and lever that would only provide propulsion when rotating in one direction, but my cardboard fabrications were hard to calibrate effectively.
I went back to the roller idea and switched to a jar which fits inside a roll of duct tape with just a little room left over. Here my hope was that the friction between the jar and the roll would be small enough that I could rock the jar back and forth and get it to work like an axle inside the tape, so that the tape would keep going in one direction. My final result uses a long lever with two quarters taped to it to create a weight that I can shift back and forth with the servo. If driven properly it works pretty good and even though it occasionally moves backwards a bit, overall it has a pretty good net gain in the forward direction.
Since the driving can be tricky, I’m still just using the potentiometer controlled servo code from lab.
~~~~~~~~~~~~~~~~~~~~~~~~
COMPONENTS
~~~~~~~~~~~~~~~~~~~~~~~~
1- Arduino Uno
1 - Breadboard
1 - Servo
1 - Potentiometer
assorted wires
jar
masking tape
roll of duct tape
cardboard
twist ties
2 - quarters
- Login to post comments
