Hi Blogbo,
You should measure the motor current. When there's an obstacle that blocks
the pad of the door the motor current will increase when the door hits the
obstacle. It's also a good idea to add an extra pair of switches near the
center, where both doors meet, so that you can reduce the speed of the motor
for the last say 30 centimeters before the doors actually close. Maybe you
should replace the mechanical switches with optical ones, doors tend to
open and close very frequent and mechanical switches will become a nuisance
if you have to replace them regularly.
on1aag.