Stage 1) adult prep
Scavenge a battery container, switch and motor from a broken toy or device. wire them together and check the the switch correctly operates the motor. tape the motor to battery pack so the shaft extends out. tape the switch so is faces in the same direction but on a neighboring face of battery case.
Stage 2) build interest
Discuss robots and what the are with you kid. Ask if she wants to make one.
Stage 3) gather materials.
Get an old box with about 15cm square of thick cardboard.
Get the scissors, tape and 4 crayons
Stage4) build it - child
Cut about a 3 cm line straight in about 3cm fold the edges up and tape the overlapping 3 cms to the next edge. this forms a kind of strong small shoe box top.
tape the motor to the inside of box lid with the drive shaft out.
tape the four crayons/texters to the four box lid corners so they point in the same direction as the motors drive shaft and extend as far as possible.
then tape the weight to the motor with a long piece of tape
Stage 5) turn it on and test - done by child
Stand the entire device on a sheet of paper so the the points of the crayons are touching the paper. and turn it on.
The weight should swing around between the crayon legs causing the whole thing to shake and rotate drawing lines in the paper.
Have your kid change the length of the tape between the weight and motor and crayon leg length and see what happens to the drawing. Ask which is better and why
What they learn
- basic engineering; prototyping and refinement
- structure and stability (odd sized legs)
- the basics of mechanical vibrations what the are and why they exist