Digital videos from experiments in our lab. Please note:

  • Videos are in real time unless stated otherwise.
  • Some of these files are very large. Be patient during downloading...
  • Depending on your browser, movies will start running during downloading, but possibly much slower than in real-time.
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  • Selfassemby of a 1mm2 silicon chiplet on a hydrophobic binding site immersed in water. MPG movie, 619kB.
  • Capillary forces align a 3mm2 PZT chip for a micropump assembly. The PZT and the binding site are hydrophilic, the remaining substrate is hydrophobic, alkane-thiol covered gold. MPG movie, 5.8MB.
  • LED after selfassembly with electroplating to establish electrical connections. MPG movie, 4.3MB.
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Micro Spacecraft Docking

  • Experiments with a simulated spacecraft (puck floating on an air table) and its positioning with microactuator arrays. This video likely represents a world record in the ratio between mass of actuator (a few micro-grams) and mass of manipulated object (45 grams). MPG movie, 32.1MB.
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Walking Microrobot

Microtubules on Patterned Kinesin Tracks

Micro Cilia

  • Closeup of a polyimide cilia array, which shows a 20mm by 15mm (approximately) section of the chip. A motion pixel executes 4-phase gaits in various directions. Quicktime movie, 640kB. More info...
  • Moving, rotating, and aligning various silicon chips. MPG movie, 1.9MB.
  • Microcilia in action - transporting an aluminum block. MPG movie, 4.9MB.
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CMOS Micro Cilia

  • Continuous rotation of a silicon chiplet on a CMOS integrated cilia array. A skewed squeeze field simultaneously generates a centering force and a torque on the chiplet. Quicktime movie, 9x, 385kB.
  • Translation and rotation of a silicon chiplet. Various operations are shown in sequence and demonstrate the programmability and flexibility of the CMOS integrated cilia array. Quicktime movie, 9x, 445kB.
  • Open-loop positioning and aligning of a square silicon chiplet (Quicktime movie, 9x) on a CMOS integrated programmable cilia array. A simple squeeze field is used to center and reorient the chiplet until a stable equilibrium is reached. Quicktime movie, 9x, 87kB.
  • A quadrilateral silicon chip is positioned an aligned open-loop in a squeeze field implemented with a single CMOS integrated cilia array. Quicktime movie, 9x, 93kB.
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Single Crystal Silicon Actuator Arrays

  • A to-scale CAD model of single crystal silicon micro actuators. The actuators are shown in yellow, the aluminum electrodes are white. If we apply an AC voltage between the silicon subtrate and the electrodes, we generate electrostatic forces that induce oscillation. The actuators are asymmetric: there are tips on just one side of the suspended actuator grid. One die contains more than 100 actuators. Dies can be "tiled" together to continuously fill the wafer with thousands of actuators. MPG movie, 1.9MB.
  • A computer animation followed by an SEM video of the actuators activated by an AC signal (note the negative charge in the SEM appearing as bright surfaces). MPG movie, 1.9 MB.
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Sensoress Manipulation with Programmable Force Fields

  • One-step alignment strategy: The object is moving in the force field until it reaches a stable equilibrium position. We can predict this position from the force field and the object geometry, and we can show that for any given polygonal part, there is only a small finite number of such positions. The force field can be generated for example by an array of micro actuators, or by a vibrating plate. MPG movie, 44kB
  • Two-step alignment strategy: With two sensorless alignment steps the object can be oriented uniquely (up to symmetry). A geometric analysis of the object shows that it has two stable equilibrium positions. From this analysis we can generate the appropriate two-step alignment strategy. MPG movie, 176kB.
  • Two-step alignment strategy: The object reaches unique orientation from 4 arbitrary initial positions after two sensorless alignment steps. MPG movie, 2MB.
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© Karl F. Böhringer, Department of Electrical Engineering, Box 352500, Seattle, WA 98195-2500, USA