Variable-ratio transmission

A transmission comprising:

• a base to which an object can be attached, the base having an axis of rotation;
• a plurality of pulley assemblies, each pulley assembly comprising one or more pulleys, a pulley shaft, and a pulley transport, the pulleys of a pulley assembly being rotatably attached to the pulley shaft, the pulleys being rotatable in only one direction about the pulley shaft, the pulley shaft being attached to the pulley transport, the pulley transport being slideably attached to the base along a radial, the pulley assemblies being so arranged that the plurality of pulleys can engage at least one encircling belt or chain;
• an actuating system that applies radial forces to the plurality of pulley transports for the purpose of maintaining the pulley assemblies in fixed radial positions or moving the pulley assemblies to other radial positions, the actuating system being controlled by an external entity, the radial forces applied by the actuating system to move the pulley assemblies to other radial positions being applied continually to the plurality of pulley transports for as long as the external source is commanding movement of the plurality of pulley transports.