I recently made a prototype version 1.3 of read rope.
It was very successful!
- The equivalent resistance at output, load, increased based on the location of bends.
- The flex sensors worked very well.
- The output voltage increased based on location of bends and made it easy to tell where bends occurred.
- The output of read rope was connected to the ADC of Arduino Uno and the arduino program verified that the bends were giving expected output voltage dependent on combination of bends.
There were 2%-6% errors on expected values vs experimental values which could be due to tolerances of resistors, tolerance of flex sensor, flex sensor being a bit bent instead of flat.
Considerations for next prototype
1. Use flexible wire that can be bent over several times.
2. Find tubing material that can enclose the wires and flex sensors.
3. Make a sample microcontroller arduino program that can calibrate the flex sensor to determine which values signify a bend. Done to work with error.