A simple motor forwards, stop then reverse to starting position when button pressed

[tperry1x]

Hi everyone. I am new to this forum, and a complete newbie to everything electronics. I really hope that someone can help me, and this will probably be a straighforward question.

What I want to do is as follows:
There are 2 push buttons, A and B.
• When button A is pressed, a motor turns clockwise until it reaches a set point. (Button B is deactivated at this point so pressing it has no effect).
• The power to the motor is then automatically cut after a set point is reached so the motor stops.
• Button B then becomes live and button A is deactivated.
• Only when button B is pressed, the motor returns to the exact point it started at to begin with.

Is it possible to automatically cut the power to the motor (in both directions) when it meets a point of resistance?

Many thanks for any help you can give.
By the way, if it helps, this would be for a custom pop-up headlight mechanism I am devising.

 

[duke37]

The motor may not like being stalled, if the current is sensed to determine the end point, then the starting current may activate the system. Limit switches would be better.
Try to get a car window winder system circuit to see how others do it.

 

[Harald Kapp]

You may have a look at the most useless machine ever (http://www.instructables.com/id/The-Most-Useless-Machine/).
There a servo motor does almost what you want, using limit switches. Other than in your scenario the useless machine automatically reverts when reaching position B. This is due to a toggle switch being used. But the circuit should be easily modified for using push buttons + limit switches.

Regards,
Harald

 

[tperry1x]

Limit switches seem the way forward. Thanks everyone, think I've got an idea on how to do this now. Answered my own question on the mechanics of this. Will put up a sketch if this helps anyone else.

 

[davenn]

You may have a look at the most useless machine ever (http://www.instructables.com/id/The-Most-Useless-Machine/).

Regards,
Harald

haha, thats so funny, love the video of the 2 duelling against each other.
a nice mantlepiece item for visitors to talk about

Dave