Harmonic Drive
Wafer-Handling-Robot Primary axes
Hollow-shaft actuator
Steel belt drive
Clean-room specification
The novel aspect of this design example is that the FHA hollow-shaft actuators used as primary axis drives are built into the base of the robot. The first axis, which drives the upper arm segment, is driven by the upper hollow-shaft actuator. The high capacity output bearing of this actuator can support the whole weight of the robot arm.
The second axis is driven by the lower actuator via a shaft passing through the hollow-shaft of the upper actuator. This is connected to the elbow joint by means of a pre-tensioned steel belt. The advantage of this solution lies in the fact that by integrating both actuators in the robot base, the mass of the arm itself is reduced, so enhancing the dynamic performance of the robot. The cables are led inside the robot arm, which allows application of the whole system under clean-room conditions.
The rotational hand axis is driven by a RS series mini servo actuator. A further interesting feature of this design is the incorporation of the AC mini servo actuator inside the elbow joint of the arm.
