Making a scribbling machine is a great way to experiment with the erratic movement of an offset motor. Basically, a Scribbling Machine, is a motorized gadget that moves in erratic ways and leaves a colorful trail which traces its path.
A scribbling machine is made from simple materials and demonstrates the erratic motion produced by an offset motor.
You can use harvested motors and switches from old, discarded toys and electronics from everyday objects like strawberry baskets and milk cartons. You can experiment with different lengths and weight of the eccentric motors, test various drawing tools, experiment with materials used for the base and increase and decrease the speed of the motors. You will be amazed at the different motions and patterns you can create.
Motor (1.5v – 3v)
Battery (AA or AAA)
Art scraps (cardboard, milk carton, strawberry basket)
Hot glue stick
Markers or pens
Strip the ends of the electrical wire and connect the motor to the battery using masking tape to secure the wires.
Experiment with ways to offset the motor (try clay, wood or a hot glue stick). Find out what happens when you change the weight on the offset motor, as well as the arm on the motor.
Build a base and attach the offset motor (try using foam board, a milk carton, a strawberry basket or other household items. Make sure there is enough clearance for your offset motor to spin.
Attach markers or pens to trace the jittering movement of your Scribbling Machine. You might want to try using a steel wire to attach the markers and pens because it makes them more responsive to the movement of the motor. You can experiment with your own designs.
Now turn it on and see what kind of designs you create!
This experiment is a great example of a low-tech activity that works well on its own, but can be made more interactive when you use sensors and microcontrollers to make it more complex.
Cell phones and pagers use offset motors when they vibrate. You can harvest a motor from a discarded phone or pager, then connect it to a battery the same way you did for your Scribbling Machine. These little motors can be used for all kinds of interesting projects.
Have fun with it, and check out all of the other great electrical experiments on our site that are easy and inexpensive to do at home.