Current sensor vs limit switch

Projects General Guidance
1

Project: Nano/MPU based Self leveling telescope pier for a mobile observatory.
Method: 3 motorized trailer jacks
Procedure: Lower jacks until they reach the ground then call a leveling subroutine that is basically a modified digital level program.
Problem: Running out of pins.
3 motor direction
3 motor enable
3 upper limit switches (detect fully retracted)
3 lower limit switches (detect start lifting)
Other sensors to detect roof open, telescope
position etc.
Proposed solution: Monitor motor amp draw with ANI 218 I2C current sensors to detect when a jack has reached ground and begins to lift and when fully retracted . The motors have a no load draw about .5A, 1.5A when lifting the telescope and 3A just before they stall.

What should I be looking out for that I have not considered.

2

Welcome to the forum

I assume that you have used the A* pins as digital pins if required ?

3

You could use a multiplexer or shift register for extra pins for your buttons

4

Did you mean the INA219 current sensor?

5

What about this: let all motor directions be wired together and only run one motor at the time.
Daisy chain all end stops and use one input. Operating one motor at the time, run it until the end swich is triggered. Then slowly back off the swich.

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