Abstract not found

Programmable vector fields can be used to control a variety of flexible planar parts feeders. These devices can exploit exotic actuation technologies such as arrayed, massively-parallel microfabricated motion pixels or transversely vibrating (macroscopic) plates. These new automation designs promise great flexibility, speed, and dexterity---we believe they may be employed to orient, singulate, sort, feed, and assemble parts. However, since they have only recently been invented, programming and controlling them for manipulation tasks is challenging. When a part is placed on our devices, the programmed vector field induces a force and moment upon it. Over time, the part may come to rest in a dynamic equilibrium state. By chaining together sequences of vector fields, the equilibrium states of a part in the field may be cascaded to obtain a desired final state. The resulting strategies require no sensing and enjoy efficient planning algorithms. This paper begins by describing our experimen...

Abstract not found

Programmable force vector fields can be used to control a variety of flexible planar parts feeders such as massively parallel microactuatorarraysortransverselyvibrating(macroscopic) plates. These new automation designs promise great flexibility, speed, and dexterity -- we believe they may be employed to position, orient, singulate, sort, feed, and assemble parts. However,since they have only recently beeninvented,programmingandcontrollingthemformanipulation tasksischallenging. Whenapartisplacedonourdevices,theprogrammed vector field induces aforce and moment upon it. Over time, the part may come to rest in adynamic equilibrium state. By chaining sequences of force fields, the equilibrium states of apart in the field may be cascaded to obtain adesired final state. The resulting strategies require no sensing, and enjoy efficient planning algorithms. This paper begins by describing new experimental devices that canimplementprogrammableforcefields. Inparticular,wedescribe our progress in building the M-CHIP (Manipulation CHIP), amassively parallel array of programmable micromotion pixels. Both the M-CHIP and other microarray devices, as well as macroscopic devices such as transversely vibrating plates, may be programmed

As improvements in fabrication technology for MEMS #microelectromechanical systems# increase the availability and diversity of these micromachines, engineers are de#ning a growing number of tasks to which they can be put. The idea of carrying out tasks using large coordinated systems of MEMS units motivates the development of automated, algorithmic methods for designing and controlling these groups of devices. We report here on progress towards algorithmic MEMS, taking on the challenge of design, control, and programming of massively-parallel arrays of microactuators. We report on these developments in this focused survey paper, based on the research results originally reported in our 1994 paper #24# and developed further in #19,20,26,21,17,18,24,12,14,15, 9#. We describe how arrays of MEMS devices can move and position tiny parts, suchasintegrated circuit chips, in #exible and predictable ways by oscillatory or ciliary action. The theory of programmable force #elds can model this acti...

Manipulation tasks with actuator arrays fabricated in MEMS (micro electro mechanical system) technology can be modeled by the theory of programmable force fields, which describes the forces generated by the actuators as planar vector fields. Given a task (e.g., unique positioning of a part) and a part geometry, we develop algorithms that automatically generate the corresponding manipulation plans as a sequence of force fields. Programmable force fields are employed as an abstraction barrier between applications requiring array micromanipulation and their implementation with MEMS devices. The theory also provides upper and lower bounds (i.e., complexity, completeness, and impossibility results) for manipulation tasks and force fields. We derive a classification of vector fields, resulting in design criteria by which efficient manipulation strategies and effective actuator arrays may be developed. This theory is applicable to a wide variety of actuator arrays. When a part is placed on th...

Arrays of electrostatic MEMS actuators have been fabricated using a multi-layer SCREAM (Single-Crystal Reactive Etching and Metallization) process. The high aspect ratio single-crystal silicon (SCS) devices consist of released, torsionally suspended grids with tips. Experiments and calculations show that the actuator array is strong enough to move macroscopic parts. An individual actuator can generate a force of approximately 10 ¯N and a displacement of 5 ¯m. We describe manipulation experiments in which small, flat objects were lifted and moved. Monolithic arrays have been built reaching a size of up to 10 cm 2 , with up to 15,000 individual single-crystal silicon actuators on one chip. MEMS actuator arrays can be used to generate a programmable force vector field for the manipulation of small, flat objects. We develop a theory of sensorless manipulation for programmable force vector fields. It is shown how simple actuator control strategies can be used to uniquely align a part up t...

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