Close

Considerations for Precision of Input and Output

A project log for Read Rope / Electronic Nerve

This is an open-source hardware project for a device that outputs a certain voltage depending on where the rope/wire is bent.

pablo-antonio-camacho-jrPablo Antonio Camacho Jr. 07/23/2019 at 02:360 Comments

One important consideration to take when developing read rope into a product is the precision of the output voltage as determined by precision of input.

  1. Precision of Output Voltage. How well can output voltage be read.
    1. The resistors used will determine the ratio of resistance between output terminal and ground to total resistance in the circuit which determines the output voltage.
      1. The tolerance of these resistors needs to be considered for when output voltage will be fed into an analog-to-digital converter which expects a precise value for a certain bend. 1% tolerance in resistors is ideal.
      2. The difference between resistors will determine the difference between output voltages at certain bends. Ideally the resistors should be on the same order to avoid 1 bend at lower end not adding noticeable amount to output voltage.
  2. Precision of Input. Where the bends can be made.
    1. Ideally for a very precise small read rope, the resistors will need to be placed very close to each other for bends to be interpreted that are very close to each other.
    2. Size of SPST switch and resistors will determine placement of resistors and size of bends.
    3. Ideally, for a large rope where only a few bends need to be read, resistors can be placed far apart from each other and connected through long wire. 

Discussions