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Build yourself a Crumble Junkbot


Over the last eight years I have been working (off and on) on a project, junkbots (http://junkbots.blogspot.co.uk/2010/01/introduction.html), in which 'junk' is used to embed environmental, engineering and computing concepts. One part that has grown from this project is using drinks cans, motor, batteries and something to unbalance the motor to produce a vibrating 'bot' that move along a smooth surface. 

To add a little more control both Raspberry Pis (http://robotsandphysicalcomputing.blogspot.co.uk/2015/07/raspberry-pi-controlled-robot-from-junk.html) and Micro:bits (http://robotsandphysicalcomputing.blogspot.co.uk/2016/09/do-it-yourself-remote-controlled.html) have been investigated.


In this post a Crumble controller from Redfern Electronics is used. The crumble controller is an excellent board for this project, it is relatively cheap, it is programmable with it's own graphical language, and it has motor drivers built in. In the figure to the left the parts (apart from adhesive tape) used can be seen.

1. Building the body.
Tape three pens (with their lids on) on to the drinks can - making a tripod arrangement. Add (tape it on usually) a motor with something on the axle to unbalanced the motor; I use broken toy propellors but mis-shapen blu-tak; clothes pegs could be used.

2. Wiring up
Using croc-clips ideally, but loops of wire if not, connect the battery to the controller and also the motors to the controller. Plug in the USB cable into the controller and the computer.

3. Running and Controlling
Make sure the Crumble software (http://redfernelectronics.co.uk/crumble/) is installed on the computer. 

An example is shown below that drives the motor forward and then backward repeatly. You might need to change the percentage values based on experiment, for the motor used. In the video below the junkbot is shown in action.






All opinions in this blog are the Author's and should not in any way be seen as reflecting the views of any organisation the Author has any association with. Twitter @scottturneruon

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