Posted: Apr 12, 2016 9:29 pm
What is the smallest incremental movement you require, beside too small to see?
You could use an escapement mechanism where you turn on the motor for long enough to complete one step of the escapement (ratchet) and move the load one smallest step. Then the motor is off for as long as you like. Motion is as slow as you like. The smallest step uses full motor power for best torque.
If you can use a counterbalance (e.g. a mass on a cord that runs over a pulley) then you can greatly reduce the torque required since most of the static load will be balanced out. If the counter balance is a bit heavier than the load then it can provide all the force to move the load and your motor only has to tip the escapement ratchet enough to let the weight drop one increment. Look at a typical clockwork balance wheel escapement and think about just rocking the ratchet with a motor (or a pendulum, or a balance wheel or a solenoid...)
You could use an escapement mechanism where you turn on the motor for long enough to complete one step of the escapement (ratchet) and move the load one smallest step. Then the motor is off for as long as you like. Motion is as slow as you like. The smallest step uses full motor power for best torque.
If you can use a counterbalance (e.g. a mass on a cord that runs over a pulley) then you can greatly reduce the torque required since most of the static load will be balanced out. If the counter balance is a bit heavier than the load then it can provide all the force to move the load and your motor only has to tip the escapement ratchet enough to let the weight drop one increment. Look at a typical clockwork balance wheel escapement and think about just rocking the ratchet with a motor (or a pendulum, or a balance wheel or a solenoid...)