Motion Control

Multi-proble microassembly based on vision and force feedback

Our motion control research is motivated by high speed and high precision requirement in electronic manufacturing. We have investigated following approaches:

High speed trajectory tracking: we use a combination of feedback and feedforward (learning-based) control to achieve high performance trajectory tracking.
Motion and force control: we use multi-camera feedback to coordinate two probes to manipulate sub-mm parts (using vision-based force control to maintain grasp stability).
Motion planning: To process multiple features in electronic manufacturing, the problem becomes a motorized traveling salesman problem. We have developed efficient suboptimal algorithms to generate practical solutions.

Research Theme

Motion

Projects

Convergent Manufacturing using Multiple Industrial Robots

Trajectory Tracking for Multiple Industrial Robots

Industrial robots are increasingly deployed in applications requiring an end effector tool to closely track a specified path, such as in spraying and welding. Performance and productivity present possibly conflicting objectives: tracking accuracy, path speed, and speed uniformity. Industrial robots are programmed through motion primitives consisting of waypoints connected by pre-defined motion segments, with specified parameters such as path speed and blending zone.

Precision Motion Control

Precision motion is an indispensable part of microelectronic systems and their manufacturing, for example, read/write head motion in disk drives, chip placement motion in surface mount machines, laser drill motion in electronic packaging, scanning motion in confocal microscope, etc. Precision motion is also critical for micro-assembly and Micro-Electro-Mechanical-Systems (MEMS) actuation in applications to RF, micro-optic and micro-fluidic devices. With the continuing demand on high performance and low cost, the requirement on the motion subsystem, in terms of speed and precision, is also ever more stringent. Due to the high volume of data or parts these systems have to process, even a few percentage of throughput increase can have major economic impacts in terms of the overall system performance improvement and production cost saving.