Biologically inspired control of quadruped walking robot

In this paper, we present a control method for a quadruped walking robot inspired from the locomotion of quadrupeds. A simple and useful framework for controlling a quadruped walking robot is presented, which is obtained by observing the stimulus-reaction mechanism, the gravity load receptor and the manner of generating repetitive motions from quadrupeds. In addition, we propose a new rhythmic pattern generator that can relieve the large computational burden on solving the kinematics. The proposed method is tested via a dynamic simulation and validated by implementation in a quadruped walking robot, called AiDIN-I (Artificial Digitigrade for Natural Environment I). Recommended by Editorial Board member Sangdeok Park under the direction of Editor Jae-Bok Song. This work was supported by the Korea Research Foundation Grant funded by the Korean Government (MOEHRD) (KRF-2005-D00031). Ig Mo Koo received the B.S. degree in Mechanical Engineering from Myongji University, Yongin, Korea, in 2003, the M.S. degree in Mechanical Engineering from the Sungkyunkwan University, Suwon, Korea, in 2005, where he is currently working toward a Ph.D. degree in Mechanical Engineering from Sungkyunkwan University. His research interests include artificial muscle actuators, haptics, tactile display, biomimetics and quadruped walking robots systems. Tae Hun Kang received the B.S., M.S., and Ph.D. degrees in Mechanical Engineering from Sungkyunkwan University, Korea, in 2000, 2002, and 2006, respectively. His current research interests focus on biomimetics and quadruped walking robot. Gia Loc Vo received the B.S degree in Mechanical Engineering form Ha Noi University of Technology in Vietnam 2003, the M.S. degree Mechanical Engineering form Sungkyunkwan University, Suwon, Korea, in 2006, where he is currently working toward a Ph.D. degree in Mechanical Engineering from Sungkyunkwan University. His research interests include legged locomotion, walking and climbing robot. Tran Duc Trong received the B.S degree in Mechatronics from HoChiMinh City University of Technology in Vietnam in 2005, where he is currently working toward a M.S. degree in Mechanical Engineering from Sungkyunkwan University. His research interests include biological inspired control and adaptive control of quadruped walking robot. Young Kuk Song received the B.S. degree in Mechanical Engineering from Sungkyunkwan University, Suwon, Korea, in 2006, where he is currently working toward a M.S. degree in Mechanical Engineering from Sungkyunkwan University. His research interests include biomimetics, hydraulic robotics system and quadruped walking robot. Hyouk Ryeol Choi received the B.S. degree from Seoul National University, Seoul, Korea, in 1984, the M.S. degree from the Korea Advanced Technology of Science and Technology (KAIST), Daejeon, Korea, in 1986, and the Ph.D. degree from the Pohang University of Science and Technology (POSTECH), Pohang, Korea, in 1994. Since 1995, he has been with Sungkyunkwan University, Suwon, Korea, where he is currently a Professor in the School of Mechanical Engineering. He was an Associate Engineer with LG Electronics Central Research Laboratory, Seoul, Korea, from 1986 to 1989. From 1993 to 1995, he was with Kyoto University, Kyoto, Japan, as a grantee of scholarship funds from the Japanese Educational Administry. He visited the Advanced Institute of Industrial Science Technology (AIST), Tsukuba, Japan, as a JSPS Fellow from 1999 to 2000. He is now an Associate Editor in IEEE Transactions on Robotics, Journal of Intelligent Service Robotics, International Journal of Control, Automation and Systems (IJCAS). His interests includes dexterous mechanisms, field application of robots, and artificial muscle actua tors.     

Generation of bipedal walking through interactions among the robot dynamics,the oscillator dynamics,and the environment: Stability characteristics of a five-link planar biped robot

We previously developed a locomotion control system for a biped robot using nonlinear oscillators and verified the performance of this system in order to establish adaptive walking through the interactions among the robot dynamics, the oscillator dynamics, and the environment. In order to clarify these mechanisms, we investigate the stability characteristics of walking using a five-link planar biped robot with a torso and knee joints that has an internal oscillator with a stable limit cycle to generate the joint motions. Herein we conduct numerical simulations and a stability analysis, where we analytically obtain approximate periodic solutions and examine local stability using a Poincaré map. These analyses reveal (1) stability characteristics due to locomotion speed, torso, and knee motion, (2) stability improvement due to the modulation of oscillator states based on phase resetting using foot-contact information, and (3) the optimal parameter in the oscillator dynamics for adequately exploiting the interactions among the robot dynamics, the oscillator dynamics, and the environment in order to increase walking stability. The results of the present study demonstrate the advantage and usefulness of locomotion control using oscillators through mutual interactions.     

Central pattern generators based on Matsuoka oscillators for the locomotion of biped robots

Biologically inspired control approaches based on central pattern generators (CPGs) with neural oscillators have been drawing much attention for the purpose of generating rhythmic motion for biped robots with human-like locomotion. This article describes the design of a neural-oscillator-based gait-rhythm generator using a network of Matsuoka oscillators to generate a walking pattern for biped robots. This includes the proper consideration of the oscillator’s parameters, such as a time constant for the adaptation rate, coupling factors for mutual inhibitory connections, etc., to obtain a stable and desirable response from the network. The article examines the characteristics of a CPG network with six oscillators, and the effect of assigning symmetrical and asymmetrical coupling coefficients among oscillators within the network structure under different possible inhibitions and excitations. The kinematics and dynamics of a five-link biped robot have been modeled, and its joints are actuated through simulation by the torques output from the neural rhythm generator to generate the trajectories for hip, knee, and ankle joints. The parameters of the neural oscillators are tuned to achieve flexible trajectories. The CPG-based control strategy is implemented and tested through a simulation. This work was presented in part at the 12th International Symposium on Artificial Life and Robotics, Oita, Japan, January 25–27, 2007     

Information gathering and searching approaches on the Web

The information accessible through the Internet is increasing explosively as the Web is getting more and more widespread. In this situation, the Web is indispensable information resource for both of information gathering and information searching. Though traditional information retrieval techniques have been applied to information gathering and searching in the Web, they are insufficient for this new form of information source. Fortunately some Al techniques can be straightforwardly applicable to such tasks in the Web, and many researchers are trying this approach. In this paper, we attempt to describe the current state of information gathering and searching technologies in the Web, and the application of AI techniques in the fields. Then we point out limitations of these traditional and AI approaches and introduce two aapproaches: navigation planning and a Mondou search engine for overcoming them. The navigation planning system tries to collect systematic knowledge, rather than Web pages, which are only pieces of knowledge. The Mondou search engine copes with the problems of the query expansion/modification based on the techniques of text/web mining and information visualization. Seiji Yamada, Dr. Eng.: He received the B.S., M.S. and Ph.S. degrees in control engineering and artificial intelligence from Osaka University, Osaka, Japan, in 1984, 1986 and 1989, respectively. From 1989 to 1991, he served as a Research Associate in the Department of Control Engineering at Osaka University. From 1991 to 1996, he served as a Lecturer in the Institute of Scientific and Industrial Research at Osaka University. In 1996, he joined the Department of Computational Intelligence and Systems Science at Tokyo Institute of Technology, Yokohama, Japan, as an Associate Professor. His research interests include artificial intelligence, planning, machine learning for a robotics, intelligent information retrieval in the WWW, human computer interaction, He is a member of AAAI, IEEE, JSAI, RSJ and IEICE. Hiroyuki Kawano, Dr.Eng.: He is an Associate Professor at the Department of Systems Science, Graduate School of Informatics, Kyoto University, Japan. He obtained his B.Eng. and M.Eng. degrees in Applied Mathematics and Physics, and his Dr.Eng. degree in Applied Systems Science from Kyoto University. His research interests are in advanced database technologies, such as data mining, data warehousing, knowledge discovery and web search engine (Mondou). He has served on the program committees of several conferences in the areas of Data Base Systems, and technical committes of advanced information systems.     

Balance control of a biped robot using camera image of reference object

This paper presents a new balance control scheme for a biped robot. Instead of using dynamic sensors to measure the pose of a biped robot, this paper uses only the visual information of a specific reference object in the workspace. The zero moment point (ZMP) of the biped robot can be calculated from the robot’s pose, which is measured from the reference object image acquired by a CCD camera on the robot’s head. For balance control of the biped robot a servo controller uses an error between the reference ZMP and the current ZMP, estimated by Kalman filter. The efficiency of the proposed algorithm has been proven by the experiments performed on both flat and uneven floors with unknown thin obstacles. Recommended by Editorial Board member Dong Hwan Kim under the direction of Editor Jae-Bok Song. This work was supported by the Korea Research Foundation Grant funded by the Korean Government (MOEHRD). This research was supported by the MKE(The Ministry of Knowledge Economy), Korea, under the ITRC (Information Technology Research Center) support program supervised by the IITA(Institute for Information Technology Advancement) (IITA-2008-C1090-0803-0006). Sangbum Park received the B.S. and M.S. degrees from Electronic Engineering of Soongsil University, Seoul, Korea, in 2004 and 2006 respectively. He has been with School of Electronic Engineering, Soongsil University since 2006, where he is currently pursuing a Ph.D. His current research interests include biped walking robot, robotics vision. Youngjoon Han received the B.S., M.S. and Ph.D. degrees in Electronic Engineering from Soongsil University, Seoul, Korea, in 1996, 1998, and 2003, respectively. He is currently an Assistant Professor in the School of Electornic Engineering at Soongsil University. His research interests include robot vision system, and visual servo control. Hernsoo Hahn received the B.S. and M.S. degrees in Electronic Engineering at Soongsil University and Younsei University, Korea in 1982 and 1983 respectively. He received the Ph.D. degree in Computer Engineering from University of Southern California in 1991, and became an Assistant Professor at the School Electroncis Engneering in Soongsil University in 1992. Currently, he is a Professor. His research interests include application of vision sensors to mobile robots and measurement systems.     

正弦驱动与传感反馈结合的双足机器人仿生行走控制

提出了一种正弦驱动与传感反馈结合的双足机器人仿生行走控制方法．所有关节由正弦振荡器驱动, 较之相互耦合的神经元振荡器更加简单;控制参数具有明晰的物理意义,便于对运动模式进行调节．传感反馈表征 了机器人的运动状态,对于保证机器人的稳定行走起着至关重要的作用．将机器人碰地、碰膝等关键运动状态作为 相位反馈,对控制力矩进行相位重置,协调各关节动作,进而实现控制器、机器人、环境的耦合．同时,从节省能量 和仿生的角度,考虑了关节运动的被动特性,确定了各关节力矩的作用区间．仿真结果表明,该控制方法能实现机 器人稳定行走,并具有良好的能效性和自稳定性.     

Tools for constructing pseudo-3D space on the WWW using images

Recently, due to advancements in virtual reality and computer graphics technologies, a virtual space that looks as real as a real space has been constructed. Accordingly, there are many studies that employ virtual spaces to support human communication and remote working. Until now, the virtual space employed by these studies has been composed of geometric models. Since the real space is very large and there are a lot of objects in the real world, the cost of modeling the real space is very high. In our previous paper,¹⁰⁾ we proposed a method for building a virtual space using image data, named theimage based non-rendering (IBNR), in order to cut down the cost. In this paper, we explain the design and implementation of the tools which we implemented to construct virtual spaces based on IBNR. With these tools, it is easy to construct and renew a large-scaled virtual space based on the real space. Takefumi Ogawa: He received his B.E. and M.E. degrees in Information Systems Engineering from Osaka University, Osaka, Japan, in 1997 and 1999, respectively. Currently, he is a Research Associate of the Infomedia Education Division, Cybermedia Center, Osaka University. He is a member of IEEE, IEICE, IPSJ, and VRSJ. His research interests include virtual reality systems and augmented reality systems. Masahiko Tsukamoto, Ph.D.: He received his B.E., M.E., and Dr.E. degrees from Kyoto University, Kyoto, Japan, in 1987, 1989, and 1994, respectively. From 1989 to February 1995, he was a research engineer of Sharp Corporation. Since March 1995, he has been an Assistant Professor in the Department of Information Systems Engineering of Osaka University and since October 1996, he has been an Associate Professor at the same department. He is a member of seven learned societies, including ACM and IEEE. His current research interests include database systems, knowledge-base systems, and distributed computing systems.     

Central pattern generator parameter search for a biped walking robot using nonparametric estimation based Particle Swarm Optimization

A parameter search for a Central Pattern Generator (CPG) for biped walking is difficult because there is no methodology to set the parameters and the search space is broad. These characteristics of the parameter search result in numerous fitness evaluations. In this paper, nonparametric estimation based Particle Swarm Optimization (NEPSO) is suggested to effectively search the parameters of CPG. The NEPSO uses a concept experience repository to store a previous position and the fitness of particles in a PSO and estimated best position to accelerate a convergence speed. The proposed method is compared with PSO variants in numerical experiments and is tested in a three dimensional dynamic simulator for bipedal walking. The NEPSO effectively finds CPG parameters that produce a gait of a biped robot. Moreover, NEPSO has a fast convergence property which reduces the evaluation of fitness in a real environment. Recommended by Editorial Board member Euntai Kim under the direction of Editor Jae-Bok Song. Jeong-Jung Kim received the B.S. degree in Electronics and Information Engineering from Chonbuk National University in 2006 and the M.S. degree in Robotics from Korea Advanced Institute of Science and Technology in 2008. He is currently working toward a Ph.D. at the Korea Advanced Institute of Science and Technology. His research interests include biologically inspired robotics and machine learning. Jun-Woo Lee received the B.S. degree in Electronics, Electrical and Communication Engineering from Pusan National University in 2007. He is currently working toward an M.S. in the Korea Advanced Institute of Science and Technology. His research interests include swarm intelligence and machine learning. Ju-Jang Lee was born in Seoul, Korea, in 1948. He received the B.S. and M.S. degrees from Seoul National University, Seoul, Korea, in 1973 and 1977, respectively, and the Ph.D. degree in Electrical Engineering from the University of Wisconsin, in 1984. From 1977 to 1978, he was a Research Engineer at the Korean Electric Research and Testing Institute, Seoul. From 1978 to 1979, he was a Design and Processing Engineer at G. T. E. Automatic Electric Company, Waukesha, WI. For a brief period in 1983, he was the Project Engineer for the Research and Development Department of the Wisconsin Electric Power Company, Milwaukee. He joined the Department of Electrical Engineering, Korea Advanced Institute of Science and Technology, Daejeon, in 1984, where he is currently a Professor. In 1987, he was a Visiting Professor at the Robotics Laboratory of the Imperial College Science and Technology, London, U.K. From 1991 to 1992, he was a Visiting Scientist at the Robotics Department of Carnegie Mellon University, Pittsburgh, PA. His research interests are in the areas of intelligent control of mobile robots, service robotics for the disabled, space robotics, evolutionary computation, variable structure control, chaotic control systems, electronic control units for automobiles, and power system stabilizers. Dr. Lee is a member of the IEEE Robotics and Automation Society, the IEEE Evolutionary Computation Society, the IEEE Industrial Electronics Society, IEEK, KITE, and KISS. He is also a former President of ICROS in Korea and a Counselor of SICE in Japan. He is a Fellow of SICE and ICROS. He is an Associate Editor of IEEE Transactions on Industrial Electronics and IEEE Transactions on Industrial Informatics.     

Adaptive splitbelt treadmill walking of a biped robot using nonlinear oscillators with phase resetting

To investigate the adaptability of a biped robot controlled by nonlinear oscillators with phase resetting based on central pattern generators, we examined the walking behavior of a biped robot on a splitbelt treadmill that has two parallel belts controlled independently. In an experiment, we demonstrated the dynamic interactions among the robot mechanical system, the oscillator control system, and the environment. The robot produced stable walking on the splitbelt treadmill at various belt speeds without changing the control strategy and parameters, despite a large discrepancy between the belt speeds. This is due to modulation of the locomotor rhythm and its phase through the phase resetting mechanism, which induces the relative phase between leg movements to shift from antiphase, and causes the duty factors to be autonomously modulated depending on the speed discrepancy between the belts. Such shifts of the relative phase and modulations of the duty factors are observed during human splitbelt treadmill walking. Clarifying the mechanisms producing such adaptive splitbelt treadmill walking will lead to a better understanding of the phase resetting mechanism in the generation of adaptive locomotion in biological systems and consequently to a guiding principle for designing control systems for legged robots.     

A fish robot driven by piezoceramic actuators and a miniaturized power supply

In this paper, we have introduced a prototype of a fish robot driven by unimorph piezoceramic actuators. To improve the swimming performance of the fish robot in terms of tail-beat angle, swimming speed, and thrust force, we used four light-weight piezo-composite actuators (LIPCAs) instead of the two LIPCAs used in the previous model. We also developed a new actuation mechanism consisting of links and gears. Performance tests of the fish robot were conducted in water at various tail-beat frequencies to measure the tail-beat angle, swimming speed, and thrust force. The tail-beat angle was significantly better than that of the previous model. The best tail-beat frequency of the fish robot was 1.4 Hz and the maximum thrust force was 0.0048 N. A miniaturized power supply, which was developed to excite the LIPCAs, was installed inside the fish robot body for free swimming. The maximum free-swimming speed was 3.2 cm/s. Recommended by Editorial Board member Hyoukryeol Choi under the direction of Editor Jae-Bok Song. This work was supported by the Korea Research Foundation under grant KRF-2004-005-D00045. Quang Sang Nguyen received the BS (2001) and MS (2006) from Hochiminh City University of Technology, Vietnam. Formerly an assistant lecturer of Naval Architect and Marine Engineering, Hochiminh City University of Technology, Vietnam (2001-2006), he is currently a Ph.D. student at the Department of Advanced Technology Fusion, Konkuk University. His specialty is biomimetic system design and smart material application. Seok Heo received the B.S., M.S. and Ph.D. degrees in Mechanical Engineering from Dongguk University in 1998, 2000, and 2003, Respectively. Currently he is a Research Professor at the Artificial Muscle Researcch Center, Konkuk University, Seoul, Korea. His research interests include biomimetics, vibration analysis, system design and control, and smart materials and structures. Hoon Cheol Park received the B.S. (1985) and M.S. (1987) from Seoul National University in Seoul, Korea and Ph.D. (1994) from the University of Maryland at College Park, MD, USA. He joined the Department of Aerospace Engineering, Konkuk University in Seoul, Korea, in 1995, and he is currently a Professor in the Department of Advanced Technology Fusion. His professional experience includes Kia Motors (1986–1988) and Korea Aerospace Research Institute (1994–1995). His specialty is finite element analysis and his recent research has focused on biomimetics. Nam Seo Goo graduated with honors in 1990 from the Department of Aeronautics Engineering of Seoul National University, and he got a masters degree and Ph.D. from the Department of Aerospace Engineering at the same university in 1992 and 1996, respectively. His Ph.D. thesis was on the structural dynamics of aerospace systems. As soon as he obtained the Ph.D. he entered the Agency for Defense development as a senior researcher. In 2002, after four years of service, he joined the Department of Aerospace Engineering at Konkuk University, Seoul, Korea, where he is currently serving as an Associate Professor of the Department of Advanced Technology Fusion. His current research interests include structural dynamics of small systems, smart structures and materials, and MEMS applications. Taesam Kang is a Professor of the Department of Aerospace and Information System Engineering, Konkuk University. He received the B.S., M.S. and Ph.D. degrees from Seoul National University in 1986, 1988 and 1992, respectively. His current research areas are robust control theories and the application of those theories with regard to flight control, development of micro-aerial vehicles and fish robots. Kwang Joon Yoon was awarded the BS (1981) and M.S. (1983) in Aeronautics Engineering from Seoul National University and Ph.D. (1990) in Aeronautics and Astronautics Engineering from Purdue. Since 1991 he has been a Professor at Konkuk University in Korea, where he is currently a Professor of Aerospace Engineering, the Director of the National Research Laboratory for Active Structures and Materials, the Director of the Artificial Muscle Research Center, and the Director of the Smart Robot Center. His current research interests include smart structures and materials, micro-aerial vehicles, and insect-mimetic micro-robot systems. Seung Sik Lee received the B.S. (1996) and M.S. (1998) in Civil Engineering from Hongik University in Seoul, Korea and Ph.D. (2003) in Civil Engineering from Georgia Institute of Technology, GA, USA. Currently he is a Senior Researcher at Korea Institute of Marine Science & Technology Promotion.     

双足机器人动态步行实时步态生成

针对双足机器人动态步行生成关节运动轨迹复杂问题,提出了一种简单直观的实时步态生成方案。建立了平面五杆双足机器人动力学模型,通过模仿人类步行主要运动特征并根据双足机器人动态步行双腿姿态变化的要求,将动态步行复杂任务分解为顺序执行的四个过程,在关节空间相对坐标系下设计了躯干运动模式、摆动腿和支撑腿动作及步行速度调整模式,结合当前步行控制结果反馈实时产生稳定的关节运动轨迹。仿真实验验证了该方法的有效性,简单易实现。     

Multiagent learning towards RoboCup

This article describes the issues in multiagent learning towards RoboCup,^1≈3) especially for the real robot leagues. First, the review of the issue in the context of the related area is given, then related works from several viewpoints are reviewed. Next, our approach towards RoboCup Initiative is introduced and finally future issues are given. Minoru Asada, Ph.D.: He received B.E., M.Sc., and Ph.D., degrees in control engineering from Osaka University, in 1977, 1979, and 1982, respectively. From 1982 to 1988, he was a research associate of Control Engineering, Osaka University. In 1989, he became an associate professor of Mechanical Engineering for Computer-Controlled Machinery, Osaka University. In 1995 he became a professor of the department of Adaptive Machine Systems at the same university. From 1986 to 1987, he was a visiting researcher of Center for Automation Research, University of Maryland, College Park, MD. He received the 1992 best paper award of IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS92), and the 1996 best paper award of RSJ (Robotics Society of Japan). Also, his paper was one of the finalists of IEEE Robotics and Automation Society 1995 Best Conference Paper Award. He was a general chair of IEEE/RSJ 1996 International Conference on Intelligent Robots and Systems (IROS96). Since early 1990, he has been involved in RoboCup activities and his team was the first champion team with USC team in the middle size league of the first RoboCup held in conjunction with IJCAI-97, Nagoya, Japan. Eiji Uchibe, Ph.D.: He received a Ph.D. degree in mechanical engineering from Osaka University in 1999. He is currently a research associate of the Japan Society for the Promotion of Science, in Research for the Future Program titled Cooperative Distributed Vision for Dynamic Three Dimensional Scene Understanding. His research interests are in reinforcement learning, evolutionary computation, and their applications. He is a member of IEEE, AAAI, RSJ, and JSAI.     

An architecture for adaptive multimedia content delivery

In this paper, we propose an architecture for multimedia content delivery considering Quality of Service (QoS), based on both the policy-based network and the best-effort network. The architecture consists of four fundamental elements: multimedia content model, application level QoS policy, QoS adaptation mechanism, and delivery mechanism. Applications based on current architecture loses their meaning by drastically degrading quality when network congestion occurs. Despite of this all-or-nothing architecture, applications based on our adaptive architecture can reduce its quality and then negotiate with the network entity, keeping its quality measure as much as possible even when network congestion occurs. We may consider a quality measure for Web pages, total page transmission time, and transmission order of inline objects as a segregation. We then define a language to specify application level QoS policies for Web pages and implement a delivery mechanism and a QoS adaptation mechanism to fulfill these policies. Kaname Harumoto, Ph.D.: He received the M.E. and Ph.D. (Eng.) degrees from Osaka University, Osaka, Japan, in 1994 and 1998, respectively. From 1994 through 1999, he was with the Department of Information Systems Engineering, Grauuate School of Engineering, Osaka University. Since November 1999, he has been an Assistant Professor in Computation Center (currently, the name has changed to Cybermedia Center), Osaka University. His research interests include database systems, especially in advanced network environments. He is a member of IEEE. Tadashi Nakano: He received the B.E. degree from Osaka University in 1999. Currently, he is a Ph.D. candidate in Graduate School of Engineering, Osaka University. His current reeearch interests include multimedia content delivery architecture. Shinji SHIMOJO, Ph.D.: He received the M.E. and a Dr.E. degrees from Osaka University in 1983 and 1986, respectively. From 1986 through 1989, he was an Assistant Professor in the Department of Information and Computer Sciences, Faculty of Engineering Science, Osaka University. From 1989 through 1998, he was an Associate Professor and since 1998, he has been a Professor in Computation Center (currently, the name has changed to Cybermedia Center), Osaka University. He was engaged in the project of object-oriented multimedia presentation system called Harmony. His current interests cover wide diversity of multimedia applications such as News On Demand System, multimedia database and networked virtual reality. He is a member of ACM and IEEE.     

基于GCIPM行走的步行机器人路径规划

介绍了利用重力补偿倒立摆方式（GCIPM）提高步行机器人行走的稳定性。该方法与以往利用线性倒立摆方式（IPM）控制的机器人相似,但是考虑了期望轨迹上机器人的迈步腿力。当基于IPM的路径规划应用到实际的步行机器人上,依据ZMP控制理论从预固定点移动时,被忽略的迈步腿力的变化在实际中使稳定性得不到保证。由于GCIPM考虑了迈步腿力的影响,仿真表明,应用GCIPM的步行机器人,稳定性得到优化提高。     

An approach to analyzing biped locomotion dynamics and designing robot locomotion controls

An approach to analyzing biped locomotion problems is presented. This approach applies the principles of Lagrangian dynamics to derive the equations of motion of locomotion gaits, state-variable techniques to analyze locomotion dynamics, and multivariable feedback to design locomotion controls. A robot model which has no knee joints or feet and is constrained to motion in the sagittal plane is chosen as a sufficiently simple model of a biped to illustrate the approach. A goal of the analysis is the design of a locomotion control for the robot which produces a walking gait having a velocity and stride length similar to those of a human walking gait. The principle feature of the approach is a much deeper understanding of the dynamics of biped locomotion than previous approaches have provided.     

Efficient Non-Repudiation Multicast Source Authentication Schemes

In secure multicast communication,Packet source authentication is a bottleneck problem due to the dynamic property of the multicast group,unreliability of data transmission and the large number of data packets.This paper proposes a novel authentication scheme called B-MSAS(Balance Multicast Source Authentication Scheme)that can be used to solve this problem,in which a new message authentication technique is introduced.This scheme dramatically reduces the signature size overhead and raises the signature rate.It provides thenon-repudiation service,high loss resistance,and can easily be scaled up to potentially millions of receivers,and hence has a sweeping applicability,It should have applications to many practical problems.     

基于主—从控制的双足机器人动步态行走

本文给出一种基于主-从控制实现双足机器人动步态行走的控制方法.该方法计算量小,可以在线规划步态及实现双脚支撑期平滑的动态切换.仿真及实验结果验证了方法的有效性及可行性,实现了变步态动态行走.实验所采用的装置为 HLTR—13双足机器人.该机器人重65kg,高1.1m,具有12个自由度.实验结果表明,本文给出的方法能较好地实现变步态动态行走。从而使机器人具有较强的环境适应能力.