I'am designing an anti collision circuit with hall effect sensors.
Mechanical principle: it's basically two squares, one smaller than the other. The largest square hits an obstacle making the magnets move past the sensors, and the movement shall stop.
The hall effect sensors goes low then the magnet is near.
Electrical Principle: My design idea is to wire the four sensors parallel with a resistor on each output pin.
In normal state the resistance would be small and a low voltage drop will appear. But then one magnet is out off range from the hall effect sensor, there will be three parallel resistors which will give a larger voltage drop.
I'am using a window comparator(good old LM324) to check the voltage and turn on a solid state relay, which turn on a power relay(controlling the movements).
The idea is that the 10k resistor should be mounted at the sensor, making it possible to detect short circuited wires(GND/10V to output)
- The difference between the two states is only 0.3V. I would like to raise this to a coupled of volts. How would you do it? (I tried with some diodes and LEDs but did not go as expected)
- Is the circuit design to sensitive ? how would you have done it?