Motion transformation

A method comprising:

• providing a key and a plunger, wherein the key comprises a motivating arm on a distal end of the key, the motivating arm comprising a displacement cam surface disposed on a ventral side of the motivating arm and a return cam surface disposed on a dorsal side of the motivating arm, wherein the displacement cam surface and/or the return cam surface are stepwise functions and the plunger comprises a displacement interface that is moved by the displacement cam surface and a return interface that is moved by the return cam surface;
• moving the motivating arm of the key along the first axis in a key displacement direction;
• moving the plunger along a second axis in a plunger displacement direction in response to the displacement cam surface moving the displacement interface, wherein the displacement cam surface moves the displacement interface by coming in contact with and applying a force to the displacement interface;
• moving the key along the first axis in a key return direction opposite the key displacement direction;
• and
• moving the plunger along the second axis in a plunger return direction that is opposite the plunger displacement direction in response to the return cam surface moving the return interface, wherein the return cam surface moves the return interface by coming in contact with and applying a force to the return interface.

An apparatus comprising:

• a key comprising a motivating arm that moves along a first axis in a linear key displacement direction and along the first axis in a linear key return direction that is opposite the key displacement direction, the motivating arm on a distal end of the key, the motivating arm comprising a displacement cam surface disposed on a ventral side of the motivating arm and a return cam surface disposed on a dorsal side of the motivating arm, wherein the displacement cam surface and/or the return cam surface are stepwise functions;
• and
• a plunger that moves along a second axis, the plunger comprising:
• a displacement interface that is moved by the displacement cam surface coming in contact with and applying a force to the displacement interface in response to the key moving in the key displacement direction to move the plunger in a plunger displacement direction, and
• a return interface that is moved by the return cam surface coming in contact with and applying a force to the return interface in response to the key moving in the key return direction to move the plunger in a plunger return direction that is opposite the plunger displacement direction.