QTR-1A with Qik 2s9v1

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1

Hi,
Could you please help with the following problem?
I’m using an Arduino Uno R3 with a QTR-1A sensor, Qik2s9v1 motor controller and a 5v geared motor.
When the motor is idle, the QTR-1A detects different values to when the motor is running.
For example:

Sensor readings when Motor idle:
81
83
82
etc…

Sensor readings when Motor running:
150
151
152
etc…

No part of the setup is moving except for the motor spindle (which is not yet attached to anything).
The sensor is stationary inside a closed box and is always pointing at the same black reflective line on a white piece of paper.

Could you please help me understand what the problem could be and how to fix it?
I was wondering if this could be caused by noise but the motor is already a low noise version (with capacitors).
Also, would the digital version of this sensor be any different?

Thanks in advance,
Paul

2

Hi, Paul.

Can you post your full program and some pictures of your setup? How is everything connected?

- Ben

3

Hi Ben,
Thanks for your reply, since your post I found that the problem was my fault.
The power supply was not sufficient, so when the motor pulled power it lead to a too little voltage on the rest of the circuit.
Sorry for that!
Thanks, Paul