This paper studies the semantics of models for discrete physical phenomena such as rigid body collisions and switching in electronic circuits. The paper combines generalized functions (specifically the Dirac delta function), superdense time, modal models, and constructive semantics to get a rich, flexible, efficient, and rigorous approach to modeling such systems. It shows that many physical scenarios that have been problematic for modeling techniques manifest as nonconstructive models, and that constructive versions of some of the models properly reflect uncertainty in the behavior of the physical systems that plausibly arise from the principles of quantum mechanics. The paper argues that these modeling difficulties are not reasonably solved by more detailed continuous models of the underlying physical phenomena. Such more detailed models simply shift the uncertainty to other aspects of the model. Since such detailed models come with a high computational cost, there is little justification in using them unless the goal of modeling is specifically to understand these more detailed physical processes. All models in this paper are implemented in the Ptolemy II modeling and simulation environment and made available online.

关键词：物理现象；超密时间；广义函数；离散型；连续型

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This paper describes our experience in trying to transfer our re-vised software engineering curriculum from UC Berkeley to other universities. We were in the first wave of Massive Open Online Course (MOOCs), and this paper lists the lessons learned about educational technology transfer from developing MOOCs. To make it easier for instructors to use MOOC material, EdX offers Small Private Online Course (SPOCs), a term that we coined.

关键词：敏捷开发；云计算；教育；MOOCs；软件即服务

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This work presents a low-complexity modular sensor grid architecture to provide a smart skin to non-convex shapes, such as a robot body and legs. To configure a sensing skin shaped by arbitrary cuts and rapid changes in designs, we use a wavefront planning approach to generate a minimum-depth spanning tree of an arbitrary topology of contiguous, regularly arranged modular sensing units on a flexible substrate wired network. A Finite State Machine protocol for extracting this topology and sensor information is shown that is robust to destructive sensor loss, device failure, and transmission noise. The architecture is designed to require as little state complexity at each node as possible to minimize the area and cost of such a network implemented in printable semiconductor technology. Simulation data show recovery from network failures and extension of the architecture to larger networks with arbitrary geometry, and a sample synthesis of the verified architecture logic is shown to have a very low state and combinational logic complexity. A proof-of-concept implementation of the architecture using microcontrollers and optical proximity sensors on a flexible substrate show integration with a Scaled Composite Manufacturing process used for Biomimetic Millirobots.

关键词：传感皮肤；模块化；仿真机器人

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This research focuses on the design and implementation of robust and energy-efficient computation architectures by employing an asynchronous self-timed design methodology. A statistical framework is first presented to analyze the energy and delay of CMOS digital circuits considering a variety of timing methodologies. The proposed analysis framework combines variability and statistical performance models, which enables designers to efficiently evaluate circuit performance, and determine the optimal timing strategy, pipeline depth and supply voltage in the presence of variability.

关键词：异步电路；CMOS；节能计算

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The goal of this thesis is to address these two problems. First, a hybrid dynamical system representation is introduced that is shown to be capable of describing the discontinuities in dynamics that occur during locomotion. In particular, such a representation is constructible from observation given an unconstrained Lagrangian which is intrinsic to the biped after the identification of the sequence of contact points that are enforced during the observed motion. Second, a specific hybrid dynamical system representation is shown to be constructible from observed data by optimally switching between the set of vector fields corresponding to all possible combinations of contact point enforcements. At this point an algorithm for the computation of an optimal control of constrained nonlinear switched dynamical systems is devised. The control parameter for such systems include a continuous-valued input and discrete-valued input, where the latter corresponds to the mode of the switched system that is active at a particular instance in time.

关键词：切换系统；最优控制；混合动力；人体运动

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This thesis explores the design of systems that can climb vertical surfaces with non-negligible dynamics in the sagittal plane. The development of a low-dimensional model addresses a lack of understanding of sagittal-plane dynamics during climbing in the space of reduced-order dynamic models of legged systems. Using a construction derived from the well-known and well-studied Spring-Loaded Inverted Pendulum (SLIP), we propose a two-legged system with both torsional and linear compliance driven by a position-controlled rotational actuator. Two simple foot models are considered to explore their effect on the dynamics and stability of the system. Results of the model indicate the existence of passively stable gaits during climbing as well as during inverted running and also suggest mechanical tuning parameters for physical climbing systems. A robotic platform capable of producing dynamic climbing behaviors is introduced. A reduced profile, sprawled posture, and improved internal mechanics allow the CLASH platform to be adapted to different climbing substrates. A passive claw engagement mechanism is proposed and tested with simulated steps to verify the design.

关键词：矢状面；最小驱动；爬壁机器人

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In this paper, we introduce an innovative software approach for building energy efficiency analysis. It takes real-time data from meters and sensors in the building, analyzes energy usage, and helps building managers to save energy.

关键词：能量效率；实时数据；建模

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This dissertation investigates the challenges of designing efficient mm-wave transmitters for both long range and short range applications,and proposes concepts and techniques that can potentially break the barriers imposed by the low cost digital CMOS process. The scope of investigation and proposal extends from the architecture level down to the transistor level. Specifically, on-chip and spatial power combining techniques are analyzed and implemented to achieve larger transmitter Equivalent Isotropically Radiated Power (EIRP). To enhance the average efficiency for modulated signals with high Peak-to-Average-Power-Ratio (PAPR), a direct digital-to-RF conversion architecture is proposed and implemented, enabling dynamic DC power scaling. Finally, a Quadrature Spatial Combining concept is introduced to eliminate the tradeoff between low insertion loss and high isolation present in a traditional Cartesian architecture with on-chip signal combiners. Prototype chips are fabricated and tested in 65nm CMOS technology to verify the proposed architectures and techniques.

关键词：无线发射器；毫米波CMOS；峰值平均功率比(PAPR)

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Two novel, low-cost tactile sensors were designed for use in palm-size (approx. 10 cm in length, under 50 g in mass) crawling robots. The first is a binary, hair-based sensor array, which uses bio-inspired polymer hairs to detect both normal and shear contact forces. The hair sensors have an average normal sensitivity under 1 gram-force (1 gf approx. 10 mN), making them adequately sensitive for use in small, lightweight robots. Furthermore, the hair sensor array has a unique laminar design that allows it to be rapidly-manufactured using a layered roll-to-roll process. In a sample application, it was shown that the binary hair sensor array can be used to estimate average ground speed and to detect high-centering when running over simple obstacles by tracking the propagation of contact along the base of a crawling robot. The second sensor discussed in this work is an analog tactile bumper array that provides robots with the ability to measure contact forces when bumping into obstacles. The sensor consists of an array of laser-cut foam structures that were mechanically designed to exhibit two force sensitivity ranges. The tactile bumper is also cheap and easy to fabricate, using an array of laser-cut foam structures with analog photointerrupters to measure force.

关键词：爬行机器人；触觉；触觉传感器

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Distracted driving is still a major concern on roadways today. According to the US Department of Transportation, in 2011, 387,000 people were injured in crashes involving a distracted driver. While there has been tremendous work in vehicular safety systems, as the velocity of the vehicle increases, threat assessment becomes more difficult to predict. In this regime, understanding how the driver behaves is critical in determining the safety of the vehicle. This work presents a framework for incorporating human driver modeling with a controller to provide a semi-autonomous system for vehicle safety. We describe how the system is built, present metrics to evaluate its utility and conduct real-time experiments with a safety controller to verify the utility of incorporating the driver’s behavior while designing a semi-autonomous system.

关键词：驾驶员；建模；分心驾驶；半自主

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