Backdrive
A backdrive is a component used in reverse to obtain its input from its output. This extends to many concepts and systems from thought based to practical mechanical applications.
Not every system can be backdriven. A DC electrical generator can be implemented by backdriving a DC electric motor, however a worm drive works only in one direction.
Example: A CNC vertical mill has a vertical lead screw on the Z-axis. A low lead screw pitch means when the driving motor power is removed such as by turning the machine off, the weight of the spindle will cause the lead screw to rotate as the spindle motor falls down. The solution to prevent back-driving is to use a finer lead screw pitch or have a locking mechanism.
