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Planning and Decision-Making for Autonomous Vehicles

Control, Robotics, and Autonomous Systems 1000年第1期1卷 187-210页

作者： Wilko Schwarting Javier Alonso-Mora Daniela Rus 1Computer Science and Artificial Intelligence Laboratory Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology Cambridge Massachusetts 02139 USA email: wilkos@csail.mit.edu rus@csail.mit.edu 2Department of Cognitive Robotics Delft University of Technology 2628 Delft The Netherlands email: j.alonsomora@tudelft.nl

In this review, we provide an overview of emerging trends and challenges in the field of intelligent and autonomous, or self-driving, vehicles. Recent advances in the field of perception, planning, and decision-making for autonomous vehicles have led to great improvements in functional capabilities, with several prototypes already driving on our roads and streets. Yet challenges remain regarding guaranteed performance and safety under all driving circumstances. For instance, planning methods that provide safe and system-compliant performance in complex, cluttered environments while modeling the uncertain interaction with other traffic participants are required. Furthermore, new paradigms, such as interactive planning and end-to-end learning, open up questions regarding safety and reliability that need to be addressed. In this survey, we emphasize recent approaches for integrated perception and planning and for behavior-aware planning, many of which rely on machine learning. This raises the question of verification and safety, which we also touch upon. Finally, we discuss the state of the art and remaining challenges for managing fleets of autonomous vehicles.

关键词： autonomous vehicles intelligent vehicles decision-making motion planning artificial intelligence verification fleet management

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High Velocity Particle Cloud Generation by Pulse Laser Ablation of Ground Glass Surface

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AIP Conference Proceedings 2006年第1期830卷 268-271页

作者： Kunihito Nagayama Yuriko Kotuska Motonao Nakahara Shiro Kubota 1Department of Aeronautics and Astronautics Faculty of Engineering Kyushu University Fukuoka 812‐8581 Japan 2Department of Computer and Communication Faculty of Engineering Fukuoka Institute of Technology Fukuoka 811‐0295 Japan 3Research Center for Explosion Safety National Institute of Advanced Industrial Science and Technology AIST Tsukuba 305‐8569 Japan

Enhancement of laser energy absorption has been demonstrated by pulse laser ablation of solid target whose surface was intentionally roughened. We have studied pulse laser ablation of roughened surface of ground glass surface by focusing a laser pulse through transparent plate from rear side. Ablation process has been observed by high speed framing camera. Burst of small fragments of glass has been observed in the present experiment. By using ns‐duration Nd:YAG laser of around 100 mJ per pulse, observed peak velocity of glass particle cloud ranges 0.5 km/s to 1.5 km/s. SEM observation of the ground glass surface revealed that virgin glass surface is covered with plenty of micro cracks, while cleavage surface structure has been evidenced in the damaged surface area.

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An Experimental Study of Effects of Overlaying Tissues on HIFU Lesion

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AIP Conference Proceedings 2007年第1期911卷 237-241页

作者： Tao Long Viren Amin Ronald Roberts R. B. Thompson Scott McClure Timothy Ryken 1Center for Nondestructive Evaluation Iowa State University Ames Iowa 2Department of Electrical and Computer Engineering Iowa State University Ames Iowa 3Department of Veterinary Clinical Sciences Iowa State University Ames Iowa 4Department of Neurosurgery and Radiation Oncology University of Iowa Iowa City Iowa

Understanding the effect of overlaying tissues on HIFU lesion is crucial for estimating HIFU dose distribution at a target tissue. We have run a series of experiments to systematically observe the effects of the overlaying tissues on the HIFU beam and ultimately the lesion created in the target tissue. First, we mapped out the HIFU transducer beam (in low power) under water without and with different overlaying tissue layers. Then, we performed a series of experiments in high power to create lesions in target tissues (e.g., liver) without and with overlaying tissues (e.g. muscle). The lesions are characterized by slicing the tissues and reconstructing the 3D lesion from calibrated pictures of the target tissue slices. The low power beam measurements show significant effects in terms of severe beam wave‐field amplitude distortion due to phase aberration introduced by velocity inhomogeneity in the overlaying tissues. These results compare well qualitatively with the computational models. The results from the high power HIFU lesions in a similar setup using various tissues, including liver and muscle, provide understanding of the significance of phase aberration in overlaying tissues and could prove useful towards high precision HIFU therapy.

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Johnson Noise Thermometry For Space Reactor Temperature Measurement

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AIP Conference Proceedings 2004年第1期699卷 567-573页

作者： David E. Holcomb Roger A. Kisner Michael J. Roberts 1aNuclear Science and Technology Division Oak Ridge National Laboratory Oak Ridge TN 37831 1bEngineering Science and Technology Division Oak Ridge National Laboratory Oak Ridge TN 37831 2Department of Electrical and Computer Engineering University of Tennessee Knoxville TN 37996

A primary difference between terrestrial and remotely located reactors is the ability to periodically recalibrate and replace the instrumentation. Because of this, space reactors place a premium on self‐calibrating, long‐term reliable instrumentation. The primary temperature measurements for the SP‐100 reactor were to be made using W/W‐Re thermocouples. However, the large gamma and neutron dose expected at the coolant outlet (>1 MGy γ; 3×1015 fast neutron fluence) combined with the high temperature (1375 K nominal; 1650 K maximum) meant that the thermocouples would drift significantly over the lifetime of the reactor. A combined Johnson noise resistance thermometer capable of performing under these extreme conditions was developed by ORNL (Carroll, 1994). Johnson noise is a fundamental representation of temperature—it is the vibration of the electronic field surrounding atoms as they thermally vibrate. Johnson noise, however, is fundamentally a small signal (∼4×10−7 Vrms for a 100 Ω resistor at 300 K, using a 100 kHz bandwidth) spread throughout the frequency spectrum. Creating the electronics and signal processing required to effectively measure and interpret the noise signal remains challenging. ORNL has recently developed closely related Johnson Noise Thermometry (JNT) electronics and signal processing capabilities under a DOE International Nuclear Energy Research Initiative Project with the Korean Atomic Energy Research Institute (U.S. DOE, 2002). An overview of the application of JNT to space nuclear power and the current status of the ORNL JNT capabilities is the subject of this paper.

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Quantitative thermal wave corrosion measurements on a DC-9 belly skin in the presence of irregular paint thickness variations

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AIP Conference Proceedings 2001年第1期557卷 483-486页

作者： Xiaoyan Han L. D. Favro Li Li Zhong Ouyang Gang Sun R. L. Thomas D. Michael Ashbaugh 1Department of Electrical and Computer Engineering Wayne State University Detroit Michigan 48202 2Department of Physics and Institute for Manufacturing Research Wayne State University Detroit Michigan 48202 3FAA NDI Validation Center (AANC) Sandia National Laboratories Albuquerque New Mexico 87106

We report the results of thermal wave measurements of corrosion thinning on painted metal aircraft belly skins. We have developed algorithms to compensate for irregular variations in paint thickness. These algorithms ...

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A Study of Effects of Tissue Inhomogeneity on HIFU Beam

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AIP Conference Proceedings 2006年第1期829卷 201-205页

作者： Viren Amin Ron Roberts Tao Long R. B. Thompson Timothy Ryken 1Center for Nondestructive Evaluation Iowa State University Ames Iowa 2Department of Electrical and Computer Engineering Iowa State University Ames Iowa 3Department of Neurosurgery University of Iowa Iowa City Iowa 3aDepartment of Radiation Oncology University of Iowa Iowa City Iowa

The potential of high‐intensity focused ultrasound (HIFU) will not be realized unless the effects of overlaying tissues are understood in such a way that allows for estimation of HIFU dose distribution at a target tissue. We employ computational models to examine the impact of phase aberration on tissue ablation. Thompson and Roberts have recently studied the effects of phase aberration on ultrasound focusing in aerospace engine materials such as titanium alloy, and have developed a computational model to examine these effects. The ultrasound beam observed after transmission through the fused quartz (homogeneous) and that observed after transmission through the titanium (inhomogeneous) demonstrate the severe beam wavefield amplitude distortion introduced by the velocity inhomogeneity‐induced phase aberration. We study applicability of this approach to model phase aberration in inhomogeneous tissues and its effect on HIFU dose distribution around the focus. It is hypothesized that the ill‐effects of phase aberration accumulate during propagation through intervening tissue in which field intensities are substantially lower than that in the focal zone, and it is therefore appropriate to use a linear acoustic model to describe the transport of energy from the transducer to the volume targeted for ablation. We present initial results of the simulation and experiments of beam measurements under water without and with different tissue layers.

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HIFU Therapy Planning Using Pre‐treatment Imaging and Simulation

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AIP Conference Proceedings 2006年第1期829卷 206-210页

作者： Viren Amin Liangshou Wu Ron Roberts R. B. Thompson Timothy Ryken 1Center for Nondestructive Evaluation Iowa State University Ames Iowa 2Department of Electrical and Computer Engineering Iowa State University Ames Iowa 3Department of Neurosurgery University of Iowa Iowa City Iowa 3aDepartment of Radiation Oncology University of Iowa Iowa City Iowa

Current HIFU challenges include amount of tissue that can be destroyed by a single exposure, the inability to treat through bone, difficulty in monitoring therapy in real‐time, and difficulty in planning the strategy before therapy. Technological advances such as multi‐transducer or array beam generator, instrumentation and image‐based guidance of HIFU treatment promise to overcome many of these problems. However, there is limited work toward HIFU dosimetry and therapy planning. We present a systematic approach for developing pre‐treatment planning and HIFU dose calculations for specific target location using simulations and imaging data. We also present initial techniques and tools towards HIFU treatment planning (targeted for open‐skull brain tumor therapy) using patient‐specific pre‐therapy imaging (e.g., CT or MRI) similar to dosimetry and planning for radiation therapy. This work has potential to aid development of optimized high‐precision HIFU dosimetry and patient‐specific planning strategies for complex and sensitive applications such as in brain tumor HIFU therapy. If successful, it potentially could reduce the guess work on dosage parameters and thereby reducing the overall treatment duration and reduced exposure to non‐target tissues.

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MEMS loop heat pipe based on coherent porous silicon technology

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AIP Conference Proceedings 2002年第1期608卷 220-232页

作者： Debra Cytrynowicz Mohammed Hamdan Praveen Medis Ahmed Shuja H. Thurman Henderson Frank M. Gerner Eric Golliher 1Center for Microelectronic Sensors and MEMS Department of Electrical Computer Engineering and Computer Science University of Cincinnati Post Office Box 210030 Cincinnati Ohio 45221-0030 2Department of Mechanical Industrial and Nuclear Engineering University of Cincinnati Post Office Box 210030 Cincinnati Ohio 45221-0030 3Spacecraft Thermal Systems NASA John H. Glenn Research Center at Lewis Field 21000 Brookpark Road Mail-Stop 301-2 Cleveland Ohio 44135-3191

This paper discusses the theory, modeling, design, fabrication and preliminary test results of the MEMS loop heat pipe being developed at the Center for Microelectronic Sensors and MEMS at the University of Cincinnati. The emphasis is placed upon the silicon micro wick and its production through a novel technique known as Coherent Porous Silicon (CPS) Technology.

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Design and Implementation of a QoL Improvement System for Visually Impaired Patients

Design and Implementation of a QoL Improvement System for Vi...

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International Conference on Advances in Computational Tools for engineering Applications, ACTEA

作者： Roy Abi Zeid Daou Jad Beaino Johnny Hawat Ramy Ibrahim Ali Hayek Josef Boercsoek Jose Javier Serrano Olmedo Mechatronics department Faculty of Engineering Université La Sagesse Beirut Lebanon MART Learning Education and Research Center Chananir Lebanon Department Lippstadt 2 Hardware Engineering University of Applied Science Hamm-Lippstadt Hamm Department of Computer Architecture and System Programming Faculty of Electrical Engineering/Computer Science University of Kassel Germany Lab of Bioinstrumentation and Nanomedicine Centro de Tecnología Biomédica Universidad Politécnica de Madrid Spain

Visually impaired people encounter several challenges in their mobility and navigation. Their daily activities are obstructed due to their inability to adapt or recognize accurately their surroundings, especially outside their house which they are more familiar with. Thus, it becomes the main reason of accidents, falling off, getting lost in unknown areas, etc. Furthermore, one of the sensory systems that helps the body to process data about the external environment is the visual system. Blind people also lose touch with the outside world, develops poor motor habits, which results in postural problems as a result. This project will assist visually impaired people in their daily life and simplify normal tasks through a system combining two previously designed projects, “Smart Shoes for Blind and Visually Impaired People”, and “Human posture monitoring device”. The multifunctional system is developed with the goal of securing safe movements for visually impaired people as well as maintaining a good back posture by detecting leaning postures (LP). The purpose of the smart shoe is to identify obstacles and protect the user from unintended accidents. A compatible Android application has been developed to alert the user when there is an obstruction or when he is walking on a wet surface. Voice alarms will be used to acoustically alert the user. If the user collapses, a message with their position will be sent right away to a relative. On the other hand, the smart vest will identify the position of the user's back and alert him to maintain a straight posture through the same application as well. As the system is dealing with human health, some safety measurements would be taken into consideration to implement a safe electrical system in order to reduce error and to increase accuracy.

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Control Across Scales by Positive and Negative Feedback

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Control, Robotics, and Autonomous Systems 1000年第1期2卷 89-113页

作者： R. Sepulchre G. Drion A. Franci 1Department of Engineering University of Cambridge Cambridge CB2 1PZ United Kingdom email: r.sepulchre@eng.cam.ac.uk 2Department of Electrical Engineering and Computer Science University of Liège 4000 Liège Belgium email: gdrion@uliege.be 3Department of Mathematics Faculty of Sciences National Autonomous University of Mexico Mexico City 04510 Mexico email: afranci@ciencias.unam.mx

Feedback is a key element of regulation, as it shapes the sensitivity of a process to its environment. Positive feedback upregulates, and negative feedback downregulates. Many regulatory processes involve a mixture of both, whether in nature or in engineering. This article revisits the mixed-feedback paradigm, with the aim of investigating control across scales. We propose that mixed feedback regulates excitability and that excitability plays a central role in multiscale neuronal signaling. We analyze this role in a multiscale network architecture inspired by neurophysiology. The nodal behavior defines a mesoscale that connects actuation at the microscale to regulation at the macroscale. We show that mixed-feedback nodal control provides regulatory principles at the network scale, with a nodal resolution. In this sense, the mixed-feedback paradigm is a control principle across scales.

关键词： feedback control excitability ultrasensitivity positive and negative feedback neuronal networks multiscale control

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