One particular pinion drives the axis (the "learn") whilst the second pinion is "preloaded" to remove the backlash (the "slave"). The preload is created electronically which has a Distinctive motor controller; these systems can also be setup to drive together during cycle times when backlash is not really significant. The https://archeresfpu.angelinsblog.com/31934424/what-does-gearbox-cvt-mean