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Electrical control of the interfacial tension between a liquid and solid ("e1ectrowetting") has been studied as a means of actuation in the microdomain (characteristic dimensions 1 fim-l mm). Electrowetting provides a means of direct fluid pumping with no moving mechanical parts, which may prove useful in a number of application areas, most notably the liquid cooling of high-density microelectronic devices. A detailed model of a test device for the study of e1ectrowetting is presented. The model describes liquid flow in a small channel, as governed as the Navier-Stokes equations, Young's equation, and Lippmann's equation (for the effect of an applied potential on interfacial tension). Simulation results are presented. Preliminary results indicate that electrowetting is a viable approach to microactuation: in a 10 fim radius channel, it may be used to generate pressures on the order of 0.01 MPa, comparable to pressures generated by existing micropump designs, which are orders of magnitude larger in size.

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Evidence suggests that transformational innovation occurs at the intersection of multiple disciplines rather than isolated within them. Design—being both pervasive and inherently interdisciplinary—has the power to transcend many disciplines and help break down the departmental “silos” that hinder such collaborative efforts. Many universities are now struggling to embrace the curricular innovations that are necessary to achieve and sustain interdisciplinary education. Given the already packed undergraduate engineering curricula, several universities have started to offer new design programs that span several disciplines at the masters and doctoral levels. In this paper, we examine the five interdisciplinary graduate design programs offered by three different universities—University of Michigan, Northwestern University, and Stanford University—that hosted the NSF Design Workshop Series in 2008–2009. Collectively, these programs represent “solutions” that span a variety of graduate degree offerings that are available and provide examples of ways to successfully navigate the barriers and hurdles to interdisciplinary design education. A recap of the NSF Design Workshop Series is also provided along with recommendations from the workshops to foster discussion and provide directions for future work.

This paper develops a technique for the design of haptic systems that guarantees the absence of oscillations. Valid components of the haptic system are general devices, virtual couplings and virtual environments, linear or nonlinear, however the current work focuses on linear components. Once developed, the method will be applied to a haptic system to investigate stability conditions for passive environments versus those for non-passive environments. Examples of computational delay and free mode environment design will be developed as meaningful design problems that fall into the category of non-passive environments.

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We present a game benchmark for testing humanswarm control algorithms and interfaces in a real-time, highcadence scenario. Our benchmark consists of a swarm vs. swarm game in a virtual ROS environment in which the goal of the game is to "capture" all agents from the opposing swarm; the game's high-cadence is a result of the capture rules, which cause agent team sizes to fluctuate rapidly. These rules require players to consider both the number of agents currently at their disposal and the behavior of their opponent's swarm when they plan actions. We demonstrate our game benchmark with a default human-swarm control system that enables a player to interact with their swarm through a high-level touchscreen interface. The touchscreen interface transforms player gestures into swarm control commands via a low-level decentralized ergodic control framework. We compare our default humanswarm control system to a flocking-based control system, and discuss traits that are crucial for swarm control algorithms and interfaces operating in real-time, high-cadence scenarios like our game benchmark. Our game benchmark code is available on Github; more information can be found at https: //sites.google.com/view/swarm-game-benchmark.