Classification of finger activation for use in a robotic prosthesis arm

Hand amputees would highly benefit from a robotic prosthesis, which would allow the movement of a number of fingers. In this paper we propose using the electromyographic signals recorded by two pairs of electrodes placed over the arm for operating such prosthesis. Multiple features from these signals are extracted whence the most relevant features are selected by a genetic algorithm as inputs for a simple classifier. This method results in a probability of error of less than 2%.     

A simulator for a bit-slice computer

A simulator has been written for a bit-slice system using 2900 series devices. The simulator is very helpful in the teaching of an advanced logic design course. The system was designed so that it could be expanded as the course progressed from a microprogrammed machine to a general-purpose computer, where the student can microprogram the instruction set. The result is that each student in a large class can have unlimited access to the bit-slice computer being discussed in class. A listing of a program and its execution is given as an example of a microcoded machine. For a general-purpose machine, one would need the microcode for the fetch and execution of the instructions stored in the RAM, the code for the program in the RAM, and the code for the MAP ROM     

School-based use of a robotic arm system by children with disabilities.

A robotic arm system was developed for use by children who had very severe motor disabilities and varying levels of cognitive and language skills. The children used the robot in a three-task sequence routine to dig objects from a tub of dry macaroni. The robotic system was used in the child's school for 12-15 sessions over a period of four weeks. Goal attainment scaling indicated improvement in all children in operational competence of the robot, and varying levels of gain in functional skill development with the robot and in carryover to the classroom from the robot experiments. Teacher interviews revealed gains in classroom participation, expressive language (vocalizations, symbolic communication), and a high degree of interest by the children in the robot tasks. The teachers also recommended that the robot should have more color, contrast and character, as well as generating sounds and/or music for student cues. They also felt that the robotic system accuracy should be increased so that teacher assistance is not necessary to complete the task.     

Stochastic estimation of arm mechanical impedance during robotic stroke rehabilitation.

This paper presents a stochastic method to estimate the multijoint mechanical impedance of the human arm suitable for use in a clinical setting, e.g., with persons with stroke undergoing robotic rehabilitation for a paralyzed arm. In this context, special circumstances such as hypertonicity and tissue atrophy due to disuse of the hemiplegic limb must be considered. A low-impedance robot was used to bring the upper limb of a stroke patient to a test location, generate force perturbations, and measure the resulting motion. Methods were developed to compensate for input signal coupling at low frequencies apparently due to human-machine interaction dynamics. Data was analyzed by spectral procedures that make no assumption about model structure. The method was validated by measuring simple mechanical hardware and results from a patient's hemiplegic arm are presented.     

A robotic vehicle for disabled children

One of the most frequent effects of physical disability is reduced or impaired mobility. There are a number of technical aids for all the cases of physical impairment but none of the systems described in the literature address the particular problems of children affected by neuromotor disorders accompanied by mental retardation. The following addresses the development of the PALMA [(plataforma de apoyo ludico a la movilidad alternative) (assistive platform for alternative mobility)] system as a tool to assist the mobility of children affected by cerebral palsy. PALMA is specifically adapted to a personalized and early cognitive development of children affected by severe neuromotor problems. The rehabilitation process based on PALMA has an impact on the interaction between children and environment, on their motor dexterity, and on decision-making ability.     

一种针对AutoCAD二维图形的数字水印算法

数字水印已经广泛应用于栅格图像,但是针对AutoCAD二维图形的数字水印方案却不多,本文提出了一种针对AutoCAD二维图形的数字水印算法,其思想是利用CAD图形的仿射不变性和最低有效位算法（Least Significant Bits,LSB）,将数字水印信息嵌入至线段的比值中。实验证明该算法对平移、旋转、缩放等攻击都能起到很好的抵抗,具有较高的安全性,是一种盲水印方案。     

A robot arm for a first course in control engineering

A small robot arm with nonlinear dynamics is an extremely useful laboratory experiment for illustrating to electrical engineering students the role that linear control theory plays in the design of electronics for industrial applications in control engineering. The robot arm is small and low power so it can be operated safely in manual mode to demonstrate clearly the complexity of its control problem. It is easy to model in its stable region of operation and elementary theory provides a model in the unstable region. Then a series of simple linear designs can be carried out to yield a linear compensator for the robot arm. This can be converted to a stabilizing electronic feedback controller that readily holds the robot arm in any position, much to the amazement of young students. In addition the experiment introduces the student to the importance of engineering procedures in dealing with difficult problems     

A biofidelic birthing simulator

The design, testing, and implementation of a novel birthing simulator (patent pending, 6 September 2005) developed specifically to research the delivery process and improve clinical training in uncommon but inevitable complicated human births is reported on. The simulator consists of a maternal model and an instrumented fetal model that are used in conjunction with an existing force-sensing system and a data-acquisition system. The maternal model includes a bony, rotatable pelvis, flexible legs, and an optional uterine expulsive system. The fetal model, which can be delivered repeatedly through the maternal model, is instrumented with potentiometers to measure neck extension, rotation, and flexion during delivery. Simulation of the brachial plexus within the model fetal neck allows measurement of stretch in those nerves at risk for injury during difficult deliveries. Elements mimic the range-of-motion properties of neonate. Two methods for measuring clinician-applied force during simulated deliveries provide trainees with the real-time assessment of their own traction force and allow researchers to correlate fetal neck motion and nerve stretch parameters with clinician-applied traction. Preliminary testing indicates the system is biofidelic for the final stages of the birthing process and can be used for training and research in obstetrics.     

A simulator for teaching MR image contrast behavior

A computer program to create magnetic resonance images simulating the main features of a magnetic resonance imaging (MR) machine was developed on a personal computer. The simulated MR images are calculated using the relevant equations describing a chosen pulse sequence on the basis of proton density,T ₁ andT ₂ images acquired from whole-body MR equipment. The imaging parameters (i.e., TR, TE, TI, etc.) are provided by the user. This program produces highly realistic simulated images and includes features such as choice of echo time, inversion time, repetition time and flip angle, as well as standard features of image display programs such as setting of window level/width, zooming and region of interest definition. A novel additional feature is the ability to define artificial pathologies in user-defined areas by specifying changes in the relaxation times and proton density. The simulator has been developed for teaching and training purposes. A prototype version has been used for teaching MRI with extremely positive reactions from students.     

A new public-domain simulator for power electronic circuits

A new public-domain simulator (SEQUEL) for power electronic circuits is described. The organization of the simulator is briefly discussed. The most important feature of the simulator is that the user can define new elements in a flexible manner. The differences between the new simulator and other simulators are enumerated. Some simulation examples are discussed to demonstrate the applications of the simulator. It is pointed out that the new simulator is particularly attractive for engineering institutes in developing countries where access to expensive commercial packages with similar capabilities may be difficult     

电子制动踏板感觉模拟器研究

分析了目前存在的几种踏板模拟器结构,基于实验得出踏板感觉模拟器特性数据,针对数据作了详细分析计算,将模拟器特性划分为明显的4个阶段.对踏板模拟器机构做了初步设计,在Pro/E中对踏板模拟器做三维建模,并基于虚拟环境对结构做仿真分析,最终根据4个不同阶段的仿真结果在MATLAB中得出该结构踏板模拟器特性,与初步设计作了对...     

A comprehensive VCSEL device simulator

This paper deals with the design and implementation of a self-consistent electrothermooptical device simulator for vertical-cavity surface-emitting lasers (VCSELs). The model is based on the photon rate equation approach. For the bulk electrothermal transport, a thermodynamic model is employed in a rotationally symmetric body. Heterojunctions are modeled using a thermionic emission model and quantum wells are treated as scattering centers for carriers. The optical field is expanded into modes that are eigensolutions of the vectorial electromagnetic wave equation with an arbitrary, complex dielectric function. The open nature of the VCSEL cavity is treated by employing perfectly matched layers. The optical gain and absorption model in the quantum-well active region is based on Fermi's Golden Rule. The subbands in the quantum well are determined by solving the stationary Schrodinger equation and using a parabolic band approximation for the electrons, light and heavy holes. The photon rate equation is fully integrated into the Newton-Raphson scheme used to solve the system of nonlinear device equations. An efficient numerical optical mode solver is used, that is based on a Jacobi-Davidson type iterative eigensolver. The latter combines a continuation scheme with preconditioner recycling. The practical relevance of the implementation is demonstrated with the simulation of a realistic etched-mesa VCSEL device.     

Dynamic modeling and adaptive robust boundary control of a flexible robotic arm with 2‐dimensional rigid body rotation

This paper investigates the control of a single‐link flexible robot manipulator with a tip payload appointed to rotate about 2 perpendicular axes in space. The control objective is to regulate the rigid body rotation of the manipulator with guaranteeing the stability of its vibration in the presence of exogenous disturbances. To achieve this, a Lyapunov‐based control design procedure is used and accomplished in some steps. First, the partial differential equation (PDE) dynamic model governing the rigid‐flexible hybrid motion of the arm is derived by applying Hamilton's principle. Next, based on the developed PDE model, an adaptive robust boundary control is established using the Lyapunov redesign approach. To this end, an adaptation mechanism is proposed so that the robust boundary control gains are dynamically updated online and there is no need for prior knowledge of disturbance upper bounds. The actuators and sensors are fully implemented at the arm boundary without using distributed actuators or sensors. Furthermore, in order to avoid control errors resulting from the spillover, control design is directly based on infinite‐dimensional PDE model without resorting to model truncation. Simulation results illustrate the efficacy of the considered method.     

Getting a handle on MATLAB graphics

Among engineers and scientists, MATLAB is one of the most popular computational packages. Part of MATLAB's popularity stems from its simple, yet sophisticated, graphics capabilities. While basic plots are relatively easy to obtain, specialized plots require a little more effort to produce. This article introduces MATLAB's Handle Graphics, which provides a mechanism to fully control and customize graphics objects in MATLAB. With a basic understanding of Handle Graphics, users can produce plots that meet the unique needs and quality standards commonly required by the profession, several examples are presented to illustrate the concepts.     

EPLOT: a machine-independent graphics system

EPLOT was designed as an inexpensive and interactive small graphics library to be run on workstations, stand-alone microcomputers and mainframes, or microcomputers used as graphics terminals. It started as a minor extension to the machine-independent UNIX PLOT library but now includes capabilities for menu and mouse operations, animation, and other functions required in student projects. EPLOT allows the easy development and transfer of interactive graphics programs between SUN, MSDOS, Amiga, ATARI, and Apple Macintosh systems. It has played an important role in the philosophy of the computer graphics course offered at the authors' institution. The scope of EPLOT is demonstrated through a series of projects and programs     

An intelligent tutoring system for a power plant simulator

In this paper, an intelligent tutoring system (ITS) is proposed for a power plant simulator. With a well designed ITS, the need for an instructor is minimized and the operator may readily and efficiently take, in real-time, the control of simulator with appropriate messages he(she) gets from the tutoring system. Using SIMULINK and based on object oriented programming (OOP) and C programming language, a fossil-fuelled power plant simulator with an ITS is proposed. Promising results are demonstrated for a typical power plant.     

500 kV变电站站用仿真机的开发与应用

介绍一种新型、投资少、见效快、应用面广、全CRT的500kV变电站站用仿真机的软、硬件构成及其功能。该仿真机运行稳定,仿真范围全面,各种动静态效果逼真,可以满足变电站日常教学、培训、反事故演习、事故预想、分析及处理训练的要求。     

Variable structure control for a two-link robot arm

In this paper, a variable structure control method for a two-link robot arm with/without look-up tables is proposed. The stability of the control system is proven. Robustness against parametric variation and external disturbance is achieved. Suitable controller gains are picked up from the angle-related tables to fulfill the control law. The proposed method retains the benefit of variable structure control and further curtails computation time. An additional advantage is that it is not necessary to measure or observe joint angular velocities.     

面向配电系统调度员培训仿真系统的设计

主要叙述面向配电系统的调度员培训仿真系统(DTS)的设计。指出了对配电系统DTS与输电系统DTS的不同要求，叙述了配电系统DTS的应用功能和实现这些功能所必须有的组成部分，并阐明了该系统的作用和特点，以及软件平台的设计和实现，最后介绍了实际应用测试的条件和情况。     

A versatile cluster-based real-time digital simulator for power engineering research

This paper presents the development of a unique parallel and distributed real-time digital simulator for power engineering research at the University of Alberta. The simulator is built entirely from commodity-off-the-shelf (COTS) hardware and software components, making it very flexible and scalable. In parallel multi-tasking operations, a combination of real-time Linux operating system and an ultra-fast network forms the backbone for the internal communication between the 16 powerful processors of the Xeon-Cluster. Field programmable gate array (FPGA)-based multi-channel digital and analog I/O ports are interfaced to communicate with the external hardware components. The model development software utilized for power applications is based on the highly customizable industry-standard MATLAB/SIMULINK environment. A detailed case study of the real-time simulation of a three-level 12-pulse vector-controlled ac drive is presented to illustrate the precision capabilities of the simulator. Multiple integration algorithms and multirate computation have been applied for the simulation of the system, with slow (machine) and fast (converter) dynamic components. Real-time simulation of the entire system has been achieved with a maximum computation time of 5.35 /spl mu/s on a step-size of 10 /spl mu/s for the first time. Results obtained from the real-time simulation have been validated with an offline simulation using PSCAD/EMTDC.