Haptic motion control for physical human support

Future robots and mechatronic systems will be required to physically support human activities. In order to reach the stage of real human-friendly physical support, they should acquire many functions such as the recognition of the real world based on complicated human actions, the transmission of the ambient information in harmony with human sensation, and so on. Since haptic sensation, as well as visual information and auditory sensation are so important for human activities, haptic motion control is one of the most important issues for the purpose. This paper now presents some haptic motion control techniques as the fundamental technology for the realization of future physical human support. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

A method for haptic motion abstraction and display based on action force directionality

Robots working in an unknown environment or a human environment have been investigated for years in the field of motion control. For the next‐generation robots, human and robot interaction technologies are needed. In particular, abstractions of human motion and motion display technologies are important. This paper proposes a method for haptic motion abstraction based on action force directionality. The action force is measured by using a master–slave robot hand system which is bilaterally controlled. Human motion is abstracted as action modes and action ratios, which are calculated from the action force directionality. Action modes express action force directionality, and action ratios express the amplitude of each action mode. Action modes are valid for motion preservation, identification of humans, and motion display systems. Thus, as one of the application of action modes, a method for motion display is also proposed. A motion display control system is designed based on action modes and action ratios. This control system presents the desired action force directionality as a velocity response depending on the human action force. The validity of the proposed method is shown by the experimental results. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 176(2): 62–70, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21126     

Recognizing the ID of modulated LED tube lights by using camera motion blur

In this paper, we present an image‐based ID recognition method for ID‐modulated light‐emitting diode (LED) tube lights by using the motion blur captured by a moving camera. This method is applied to a novel camera‐based indoor positioning system, which can provide exact location for mobile users. In this system, high‐intensity LED tubes are used concurrently as the illumination devices and optical markers. The flashing of each LED lamp is modulated, and the entire tube expresses an ID message, which can be captured by a normal camera installed in a mobile terminal. The flashing occurs at a high frequency and without degrading the illumination function. However, when the exposure time of the camera is longer than the flicker period of the LED lamps, it is difficult to capture the ID pattern. We propose a method that uses motion blur to overcome this limitation. During the period of exposure, if the user manually shakes the camera in the proper direction, a streaked pattern is developed on the captured image frame, which can be used for retrieving an ID number. Moreover, we can also obtain position estimation of the terminal from motion‐blurred images. Experimental results show that with careful operation it is feasible to recognize the ID of LED tubes successfully. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

低功耗便携式运动能耗检测系统的设计与研究

为促进人们加强锻炼,设计了一种低功耗便携式运动能耗检测系统.该系统通过分析加速度的周期性来估算步频,通过步频估算出运动路程以及利用VM3C方程预测人体运动消耗.同时,通过射频技术将运动信息传输到上位机并存储,由上位机来进行用户档案信息管理、计步、路程与运动能耗等分析等功能.该运动能耗检测系统使得能耗信息的采集和数据分析查询更加便捷.     

基于MEMS传感器的运动加速度提取技术研究

结合多种现有物体运动加速度测量方法的特点,提出了一种基于MEMS运动传感器低成本且便捷的运动加速度测量方法。该方法采用多传感器数据融合技术实时求解物体的运动姿态,进而从MEMS运动传感器的实测数据中提取物体运动加速度。通过搭建基于MEMS运动传感器的加速度测量系统对该方法的可行性进行试验验证,试验结果表明,在静止状态下该方法的加速度求解误差为0.03 m/s2,与MEMS加速度计采集精度基本一致,具有较高的求解精度;在自由落地运动时该方法的加速度求解误差为0.07 m/s2,虽然物体长时间剧烈运动时耦合运动加速度会降低求解精度,但在短时间运动时仍具有较高求解精度。     

Functionalization of tactile sensation for robot based on haptograph and model decomposition

In the real world, robots should be able to recognize the environment in order to be of help to humans. A video camera and a laser range finder are devices that can help robots recognize the environment. However, these devices cannot obtain tactile information from environments. Future human‐assisting robots should have the ability to recognize haptic signals, and a disturbance observer can possibly be used to provide the robot with this ability. In this study, a disturbance observer is employed in a mobile robot to functionalize the tactile sensation. This paper proposes a method that involves the use of the haptograph and modal decomposition for the haptic recognition of road environments. The haptograph presents a graphic view of the tactile information. It is possible to classify road conditions intuitively. The robot controller is designed by considering the decoupled modal coordinate system, which consists of translational and rotational modes. Modal decomposition is performed by using a quarry matrix. Once the robot is provided with the ability to recognize tactile sensations, its usefulness to humans will increase. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 177(2): 49–57, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21169     

Fatigue recognition using EMG signals and stochastic switched ARX model

The man–machine cooperative system is attracting great attention in many fields, such as industry, welfare, and so on. The assisting system must be designed so as to accommodate the operator's skill, which might be strongly affected by fatigue. This paper presents a new fatigue recognizer based on the electromyogram (EMG) signals and the stochastic switched ARX (SS‐ARX) model which is one of the extended models of the standard hidden Markov model (HMM). Since the SS‐ARX model can represent complex dynamic relationship which involves switching and stochastic variance, it is expected to show higher performance as a fatigue recognizer than when using simple statistical characteristics of the EMG signal and/or standard HMM. The usefulness of the proposed strategy is demonstrated by applying it to a peg‐in‐hole task. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Advanced motion control by multi‐sensor‐based disturbance observer

Motion control has been widely used in industry applications. One of the key technologies of motion control is a disturbance observer, which quarries a disturbance torque of a motion system and realizes a robust acceleration control. The disturbance observer can observe and suppress the disturbance torque within its bandwidth. Recent motion systems have begun to spread in society and are required to have the ability to make contact with the unknown environment. Such a haptic motion requires a much wider bandwidth. However, since the conventional disturbance observer attains the acceleration response by the second‐order derivative of position response, the bandwidth is limited because of the derivative noise. This paper proposes a novel structure of a disturbance observer. The proposed disturbance observer uses an acceleration sensor for enlargement of bandwidth. Generally, the bandwidth of an acceleration sensor is from 1 Hz to more than 1 kHz. To cover the DC range, the conventional position sensor‐based disturbance observer is integrated. Thus, the performance of the proposed multisensor based disturbance observer (MSDO) is superior to the conventional one. The MSDO is applied to position control (infinity stiffness) and force control (zero stiffness). The experimental results show the viability of the method proposed. © 2006 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Development of a whole‐body haptic sensor with multiple supporting points and its application to a manipulator

This paper proposes a whole‐body haptic sensing system that has multiple supporting points between the body frame and the end‐effector. The system consists of an end‐effector and multiple force sensors. Using this mechanism, the position of a contact force on the surface can be calculated without any sensor array. A haptic sensing system with a single supporting point structure has previously been developed by the present authors. However, the system has drawbacks such as low stiffness and low strength. Therefore, in this study, a mechanism with multiple supporting points was proposed and its performance was verified. In this paper, the basic concept of the mechanism is first introduced. Next, an evaluation of the proposed method, performed by conducting some experiments, is presented. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 182(1): 48‐56, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22310     

A study of centralized voltage profile control of distribution network considering dynamics of distributed generator

In a future distribution network, it will be difficult to maintain system voltage because a large number of distributed generators are introduced into the system. The authors have previously proposed a voltage profile control method using power factor control of distributed generators. When all information on the system is available, an ideal stationary solution of control orders to distributed generators is given by an optimization calculation. However, it is difficult to apply optimization control in real time because a long calculation time is required for the optimization. Therefore, it is possible that a voltage change may occur before the power factor control has finished. Thus, in this paper, we develop a new control method which can save the excessive voltage changes by taking into consideration the controlled response time of distributed generators. The proposed method was tested in a 24‐node distribution network model. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 179(1): 29–39, 2012; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21231     

一种高分辨率机载SAR实时运动补偿系统设计

SAR系统要实现连续地实时成像,必须具备1套稳定可靠的实时运动补偿系统。本文设计了1种基于GPS和惯性测量器件组成的SAR实时运动补偿系统,该系统能够稳定地实时地输出载体的运动信息,不受目标场景约束,并且运算量适中,适合在飞机载体有限的体积、功耗约束下实现高实时性的运动补偿系统。实际的SAR载机飞行试验证明本文设计的实时运动补偿系统能够支撑SAR系统完成长时间连续的实时成像。     

A new approach for motion capture using magnetic field : models,algorithms and first results

Indoor and outdoor applications such as sports and health monitoring as well as realistic 3D movie and game animations require ambulatory motion capture. Thus, creating a new low‐cost light‐weight wearable motion capture system that offers realistic motion estimates is of great interest. This paper presents a new approach for ambulatory human motion capture, featuring a body mounted magnetic field source and magnetic field sensors together with an estimation algorithm. A complete study of the model, the hardware, and the estimation algorithms is presented. Results obtained in the context of motion capture of human upper limbs illustrate the proposed approach.Copyright © 2014 John Wiley & Sons, Ltd.     

基于欧拉角的关节活动度测量系统

人体关节活动度的测量在司法鉴定、康复医学等领域有着重要的意义。设计并实现了一种基于欧拉角的关节活动度测量系统,系统利用光学定位设备获取标记点位置信息,通过旋转矩阵变换与欧拉角反解算法计算角度,实现了精确、实时的关节活动度测量。系统适用于人体颈部关节、腰部关节、肩关节、肘关节、腕关节、髋关节、膝关节以及踝关节的活动度测量。精度验证实验结果显示,系统的测量精度可达到0.3°。     

Restraint method of voltage total harmonic distortion in distribution network by power conditioner systems using measured data from IT switches

The amount of distributed generation (DG) such as photovoltaic systems and wind power generator systems installed in distribution systems has been increasing because of reduction of the effects on the environment. However, harmonic problems in the distribution system are a concern in the context of increased connection of DGs through inverters and the spread of power electronics equipment. This paper proposes a method for the restraint of voltage total harmonic distortion (THD) in a whole distribution network by active filter (AF) operation of multiple power conditioner systems (PCSs). It also proposes a method for determination of the optimal gain of AF operation so as to minimize the maximum value of voltage THD in the distribution network by real‐time feedback control with measured data from information technology (IT) switches. In order to verify the validity of the proposed method, numerical calculations are carried out using an analytical model of a distribution network of interconnected DGs with PCSs. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 182(3): 19–29, 2013; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22354     

Automatic driving system using identification of switched systems with unknown switch points

In this paper, we propose a modeling method for evaluating drivers' driving skill, with which automatic driving of a vehicle is realized. The method is to formulate the automatic driving system of a vehicle as a switched system with unknown switch points by using the hinging hyperplane auto regressive eXternal (HHARX) model, which can extract driving operation modes and their switch conditions simultaneously. To verify the effectiveness, we apply the proposed method to an automatic driving system of a small remote‐controlled vehicle, instead of a real vehicle. Simulation results illustrate that the obtained models can achieve functions such as start acceleration, normal traveling, stop deceleration and auto steering in the automatic driving system. © 2006 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Indoor navigation system using ID‐modulated LED tube lights

This paper presents the design, implementation, and evaluation of a novel camera‐based information transmission system for indoor positioning and navigation. This system, which avoids the use of any expensive equipment, is of particular benefit for infrastructure consumption and is completely portable using a handheld terminal. A high‐intensity light‐emitting diode (LED) tube, which is expected to be the main illumination source for the next generation due to its lower power cost and longer lifetime, is utilized as an optical beacon in the system. LED tubes are encoded to transmit ID information, which is received by a single normal camera. The handheld computing terminal, a mobile phone for example, can query a database after performing ID recognition and, finally, the position and orientation of the terminal can be obtained. Experimental results confirm the accuracy of the system in terms of both position and orientation, and it is suitable for many indoor navigation applications. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

基于GSM短消息的测试数据远程传输技术研究

远程数据采集系统广泛用于远程技术支援,但一些传统的远程数据采集系统具有一定的缺点和不足,如造价较高,维修不便。在数据量不是很大,实时性要求不是很高的场合,利用GSM短信进行设备测试数据的远程传输是一种较好的选择。设备测试数据的远程传输系统利用文本文件读取信息和测试数据,将信息和数据编码成数据包,并将串口通信技术、多线程技术应用于GSM短消息数据包的远程传输过程中,接收到信息之后进行数据包的解码和数据的分析。文中给出了利用Visual C＋＋6．0串口通信技术开发基于GSM短消息的设备测试数据远程传输系统的关键部分和软件开发流程图。目前该系统已成功应用于设备监测现场,取得了良好的效果。     

Hybrid system reduction method using a reduced system regulator

In order to analyze the transient stability of large‐scale power systems, it is advantageous to apply the system reduction method to external systems. The short‐circuit current method is a typical engineering reduction technique. However, the dominant eigenvalues are not necessarily conserved in the reduced system. Therefore, the hybrid reduction method, in which controller parameters are adjusted to conserve the dominant eigenvalues, was proposed. Automatic voltage regulators (AVR) and power system stabilizers (PSS) have been used for parameter adjustment so far. However, since there are many parameters in AVR and PSS, complicated procedures are required to adjust them. Therefore, in this paper, the reduced system regulator (RSR) is proposed for the hybrid system reduction method. The RSR has only two parameters for adjustment. It is easier to adjust the RSR than AVR/PSS. In addition, the initial gains of the RSR are set to zero so that the dynamic behavior of the system is not influenced before adjustment. The effect and accuracy of the hybrid system reduction method with RSR are examined using a typical longitudinal power system, the IEEJ WEST 10‐machine system model. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 179(4): 33–40, 2012; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21258     

Design of a haptic data visualization system for people with visual impairments.

Data visualization is a technique used to explore real or simulated data by representing it in a form more suitable for comprehension. This form is usually visual since vision provides a means to perceive large quantities of spatial information quickly. However, people who are blind or visually impaired must rely on other senses to accomplish this perception. Haptic interface technology makes digital information tangible, which can provide an additional medium for data exploration and analysis. Unfortunately, the amount of information that can be perceived through a haptic interface is considerably less than that which can be perceived through vision, so a haptic environment must be enhanced to aid the comprehension of the display. This enhancement includes speech output and the addition of object properties such as friction and texture. Textures are generated which can be modified according to a characteristic or property of the object to which it is applied. For example, textures can be used as an analog to color in graphical displays to highlight variations in data. Taking all of these factors into account, methods for representing various forms of data are presented here with the goal of providing a haptic visualization system without the need for a visual component. The data forms considered include one-, two-, and three-dimensional (1-D, 2-D, and 3-D) data which can be rendered using points, lines, surfaces, or vector fields similar to traditional graphical displays. The end result is a system for the haptic display of these common data sets which is accessible for people with visual impairments.     

An adaptive robust observer for velocity estimation in an electro‐hydraulic system

This paper proposes the design of an observer to estimate the velocity of an electro‐hydraulic system by using pressure measurements only. The difficulties involved in the design of an observer for such a system include the highly nonlinear system dynamics, severe parametric uncertainties such as large variation of inertial load and unmatched model uncertainties. In order to address these issues, a nonlinear model‐based adaptive robust observer is designed to estimate the velocity. The contributions of the proposed work is twofold. First, it introduces a novel coordinate transformation to reconstruct the velocity estimate. And second, from a structural viewpoint, the design has two important features: (i) an underlying robust filter structure, which can attenuate the effect of uncertain nonlinearities such as friction and disturbances on the velocity estimation, and (ii) an adaptation mechanism to reduce the extent of parametric uncertainties. Experimental results on the swing motion control of an electro‐hydraulic robot arm demonstrate the effectiveness of the proposed observer. Copyright © 2012 John Wiley & Sons, Ltd.