Using new lightweight materials and an optimized design, Harmonic Drive has developed the SHD-2UH-LW Lightweight Series, available through Electromate. These axially compact gear units feature a large hollow input shaft and a robust cross roller bearing so loads can be mounted directly to the unit without the need for additional support bearings. The series was designed to be the most compact, lowest weight, hollow shaft precision gear unit available in the market today. This weight savings increases the “Torque Density” of the gear making it suited for many applications including: industrial robots, allowing operation with higher acceleration rates and payload capacity; and mobile robots, allowing lower weight designs which improves battery life without sacrificing performance. This gear unit has zero backlash, exceptional position accuracy and repeatability. The gearhead incorporates a Harmonic Drive gear component into an aluminum housing. The gearhead also features a high capacity cross roller bearing and a flanged output to mount the moving load without the need for additional support bearings. The ample hollow shaft allows cables, shafts or pipes to pass directly through the axis of rotation.