Micro/macro force-servoed gripper for precision photonics assembly and analysis

Abstract

Photonics is a field that straddles both the macro and micro worlds. It largely deals with macro-scale devices, but many of these require sub-micron-scale precision in assembly. This makes it a very interesting application domain. We describe a microgripper for microassembly of photonic devices and micro-exploration of the properties of sub-micron attachment means (such as solder and UV epoxy). The microgripper has multi-degree-of-freedom actuation and a unique micro/macro actuator on the gripping axis to facilitate human loading and unloading and also very precise accommodation. We demonstrate the force sensitivity and stiffness of approximately 20 mN and 70 mN/um, respectively to be sufficient for the intended tasks. Finally, we demonstrate the gripper accommodating forces of a large solder ball freezing and cooling as a prelude to our intended study of sub-millimeter solder balls in sub-second heating regimes.