Abstract: A semiconductor wafer pod payload platform is operable for rotation in response to linear movement of the platform by a cam assembly having rollers adapted to engage a cam surface. The payload platform is rotatably attached to a shuttle platform adapted for movement along linear rails. The shuttle platform is supported by shuttle glides adapted to move along the linear rails. A cam follower assembly is connected to the payload platform through a shaft extending through the shuttle platform and operable to rotate the payload platform. A cam surface substantially parallel to the linear rails is adapted to engage rollers on the cam follower assembly. Linear movement of the shuttle platform causes the rollers on the cam follower assembly to engage the cam surface and dispose the cam follower assembly so as to rotate the payload platform via rotation of the shaft.