I am of intermediate skill level with electronics and hardware. I am working on a linear actuator concept prototype with a partner that we plan to iteratively develop and eventually take to market for in home applications. It's primary array of use is for drawers, small doors, pop out shelves, etc. We are currently using a set of small limit switches, positioned in parallel to the axis of motion, (signal lines to an Arduino controller) to control the actuator's travel bounds, operates with a NEMA 23 motor.
Several weeks ago we integrated a second set of external limit switches just a short distance beyond each of the first set. This second set runs a voltage line of the motor through these second switches before it reaches the motor. We mean for this to act as a safety feature that will shut off the motor if the traveling component goes beyond either of the intended first switch set positions.
For a number of reasons, this temporary solution will not work in the final design. Therefore, we need some other alternative to limit the travel while also ensuring safety with using the high torque motor. Ultimately, we would like to have a single limit switch or other electromechanical component that limits the travel length while also ensuring safety under operation from the high torque motor.
My question is:
How do other similar commercially available products that use high torque motors accomplish this while ensuring safety? Are additional fuses, switches, or relays typically used in combination to prevent catastrophic failures? How can we guarantee the motor will stop when it hits the switch or component, even if there is a hardware failure or software error?
Thank you for reading my post. I greatly appreciate any insight.
