Some linear motion control systems use actuators and rollers as the basic components of the linear motion control system. Some other systems use linear bearings, which are either rollers or bearings mounted on an axial shaft. Many of these linear motion control systems also include linear gears that are used to transfer torque from one component to another. The power supply for a linear motion control system usually consists of a series of lead-acid batteries, which provide energy to the devices when they are required