1) Bend Sensor - I used this bend sensor.
2) 10K ohm resister - This divides the voltage for output with the bend sensor.
3) Solderless bread board and wires - This is an easy way to wire up this circuit.
4) Multi meter - I uses a Fluke DMM, but any way to measure voltage would be fine.
5) 5 volt power source - This may be different if your LED requires a different voltage.
This sensor works like a charm. I will be using these as feelers in future robot projects. The only surprise was that they only change resistance when bending them one way so I will need to take that into consideration when placing them on my robot. The resistance on the bend sensor starts around 11K and goes to 15K with just a little pressure to bend it. I tried bending it in a circle and that made the resistance go to 40K.
The circuit I made for testing was a simple voltage divider circuit. I will just need to hook this up to an analog input on my microcontroller and I'll look for a change in voltage to determine a collision. This seems to be a very simple and reliable sensor to use.
Here is the circuit diagram: Bend Sensor Circuit Diagram
Here are some pictures: Pic 0, Pic 1
Please email any questions/comments/errors to firstname.lastname@example.org.