A torsion based shear mode energy harvester is used to power a wireless sensor module consisting of a microcontroller, a temperature sensor, an accelerometer and a wireless transmitter. A 10 cm3energy harvester was used and was found to produce nearly 450 μW of maximum power through an optimal load resistance under 0.5 gpkacceleration excitation at its resonant frequency. This harvester was then tested using a standard diode bridge rectifier which was assessed for its suitability in powering the wireless sensor module.

Experimental results of micromirrors sealed in vacuum and non-vacuum environments are presented. The micromirror is 1.0 mm in diameter and is supported by four electrostatic repulsive actuators. The micromirror exhibits linear out-of-plane motion and rotational motion in two axes. The measured data shows that translational motion is 71 μm and 76 μm at 200 V for vacuumed and non-vacuumed micromirrors, respectively. The maximum optical rotational displacements for the vacuum and non-vacuum packaged micromirrors are 1.0° and 1.1°, respectively at 160 V. Packaging the micromirror in a vacuum decreases the squeeze film damping in the system. The settling time for the vacuum packaged micromirrors is 75 ms with an average overshoot of 116%. The settling times for the non-vacuumed micromirror are 2.75 ms with 5% overshoot for downward motion and 3.32 ms with 48% overshoot for upward motion. The estimated resonant frequency of the vacuum packaged micromirror is 2900 Hz, whereas the resonant frequency for the non-vacuumed micromirror is 1400 Hz. The static and dynamic results for the micromirror in reduced pressures determined that effects approaching the breakdown voltage become evident, resulting in lower displacements, and squeeze film damping effects are mitigated, leading to more consistent performance characteristics such as settling time and percent overshoot.

This paper presents a novel method for the time-optimal interception of moving objects in the presence of obstacles. The proposed method not only provides time-optimal positional interception, but, also simultaneously matches the velocity at which the object is moving in a dynamic environment with static and/or moving obstacles: A rendezvous-guidance technique is utilized in conjunction with a modified cell-decomposition method. Simulation and experimental results clearly demonstrate the efficiency of the proposed interception method.

This paper presents a novel method for the time-optimal rendezvous of an autonomous vehicle with moving targets in the presence of dynamic obstacles. This interception problem is addressed by utilizing the velocity obstacle approach of Fiorni and Shiller augmented with a rendezvous-guidance algorithm. However, the velocity obstacle approach had to be modified to ensure that the real-time planned path deviates minimally from the one generated by the rendezvous-guidance algorithm. Simulation and experimental results, some of which are presented in this paper, clearly demonstrate the efficiency of the proposed interception method.