Desktop Rapid Prototyping Millirobots

The development of centimeter scale mechatronic systems and measuring instruments could be greatly enhanced by the creation of a rapid prototyping capability which includes flexible microassembly of structure, joints, sensors, actuators, electronics, and wiring. Microassembly provides the ability to construct 3-dimensional heterogenous microsystems by joining sensors, actuators, structures, and intelligence, which are separately fabricated, and ideally available off-the-shelf.

We propose to develop a millirobot system which can be used for rapid prototyping of complicated micromechatronic devices combining folded-sheet structures, commercial sensors, actuators, and grippers. We will develop and test algorithms for deterministic, 3D micro-assembly. Our assembly algorithms will include both local sensor-based force control for precise alignment, and sensorless assembly algorithms. This micro-manipulator system is both a necessary tool for flexible assembly of microsystems, and a sophisticated microsystem itself.

The key research issues to be addressed in this work are:

> Develop flexible fabrication methods using fixtures and millirobots to fold pre-cut sheets of material into 3D microstructures and bond in final configurations

> Develop microassembly techniques using millirobots capable of precisely attaching 100 micron blocks as well as 12 micron or thinner sheets (such as strain gauges) through control of interaction forces

> Develop automatic algorithms which can "compile" an assembly plan, consisting of gripper and tool operations and fixture locations, which can then be used to rapidly prototype a complete microsystem, such as a 25 mm wing span micromechanical flying insect (MFI), including thorax structure, strain gauges, and piezoelectric actuators

> Design a low-cost rapid prototyping millirobot system which can be readily copied to provide a micro-tool construction capability for any lab or school interested in developing micromechatronic systems
Our goal is to allow a micro-system designer to go from design to first prototype in several hours, with additional prototypes being produced in minutes. In the first stage of the prototype fabrication, a millirobot containing grippers and tools customizes the workspace by positioning and bonding fixtures at appropriate locations. The passive fixtures are designed to dramatically reduce the complexity of the millirobot actuation, sensing, and control. In effect, fixtures will be used to maximize offline planning, and minimize millirobot hardware. In the second stage of fabrication, the millirobot system can construct the prototype, and future copies of the prototype can be quickly made without any additional workpiece setup time.

*This project is not officially supported through CITRIS funds, but the faculty and topical affiliations are sufficiently strong that it is listed here for referral and convenience.