Lab 3: Electronic Sensors
Tilt Sensor-Switch
A tilt sensor uses some kind of moveable conductive material, such as liquid mercury or steel balls, to close a switch. When the sensor is tilted, gravity pulls the conductive material down so it bridges a gap in the circuit. This tilt sensor is housed inside a folded paper “pillow box.”
Materials
- Copy paper
- COpper or aluminum foil tape
- Clear tape
- CR2032 coin battery
- LED
- Jingle bell (from crafts store), metal button, copper penny, or aluminum foil wadded up into a ball, about 1 inch diameter
Step 1
Copy or draw the template onto the piece of paper so that the box is about 6.5 inches long and the battery fits in the marking. Cut along the solid lines. This design uses slits in the paper to hold the battery in place instead of a binder clip. Carefully cut open the slits as shown on the template.
Step 2
Fold up the box along the dotted lines. Follow the curve of the lines on the sides. When you tuck them in, the box should look like a little bed pillow. Unfold.
Step 3
Lay the metallic tape along the circuit line that connects the battery and the LED. Next, fold over about one inch of tape so that it sticks to itself to make a flap that will go on top of the battery. Then run the rest of the piece of tape up to the switch area, being at the corner. That lay the third piece of tape as show. Make sure to leave space between the two pieces of tape that run next to each other at the switch area.
Step 4
Place the LED where shown. It should lie flat against the paper. Make sure the leads overlap the. metallic tape on either side. If necessary, bend and/or trim the leads to fit. Then use the metallic tape to attach it securely to the circuit.
Step 5
Slip the battery into the slits you cut, positive (smooth) side up. Fold the flap of metallic tape on top. Secure it with clear tape. Then cover the entire circuit EXCEPT for the “switch” area with more clear tape.
Step 6
Refold the box. Use tape to hold the straight side and one curved side securely closed. Open the other curved end and insert the metallic ball, then close it up again. Test your tilt sensor by turning it so that the ball rolls over the “switch” area. The LED should make the paper box glow!
