ATI-Industrial Automation, represented in Australia by Romheld , has released a range of compensator units that overcome lateral and cocking misalignment errors due to machine inaccuracy, vibration and tolerances, thereby lowering contact forces and avoiding both part and tooling damage.
Misalignment between mating parts during robotic and other automated assembly processes is a major problem that can now be accommodated by using remote centre compliance (RCC) devices. A typical application for the compensator units is peg-in-hole insertion, where one part must be inserted into another such as dowel pin insertion and shafts into bearings. The compensator device projects a compliance centre towards the insertion point, allowing the peg to align itself with the hole. The compliance centre is a point in space where an applied force causes only translation and an applied moment causes only rotation.
When the compliance centre is near the insertion point the force caused by the chamfer and sliding contact will cause the peg to translate into the hole. If two-point contact occurs when the compliance centre is near the insertion point the moment caused by the contact corrects the rotational error, aligning the peg with the hole.
The compensator is a mechanical device that uses high-quality elastomer shear pads to control compliance. In robotic applications the compensator is mounted between the end effector and the robot arm to provide a supple wrist. It lets a misaligned part translate and/or rotate in response to insertion reaction forces to prevent jam-ups.
It is available in a range of sizes to suit most robot and automated assembly machines., The units consist of a top plate (mounted to a robot), a bottom plate (for fixing tooling), three or six shear pads and overload pins. Options include a pneumatic lock-up device which centres and locks the top and bottom plates to eliminate vibration during fast accelerations of the robot or machine.
Applications for the compensator include locating parts in machines, assembling gears onto splined shafts, positioning on assembly lines, assembly of bearings to drive assemblies, fitting washers onto shafts and placing fans onto motor shafts.