新型智能机器人触觉传感服装阵列标定的研究

为使智能机器人在汽车冲撞试验中获得准确的触觉信息,研发了一种基于导电橡胶压阻特性的新型触觉传感服装阵列.针对该传感阵列设计了静态标定试验装置,在常温下(25℃)研究了不同型号的导电橡胶( N05,N10,N15)的压阻行为特性,选出压敏性最佳的N10作为触觉传感服装的敏感元件;在此基础上提出了标定方案,标定结果表明:高...     

Force sensing for advanced robot control

Although several force sensing devices have been developed recently, industrial applications of these devices are rarely found. This is in severe contradiction to the growing success of vision systems. In many application domains however, tactile perception may be as important as vision. This paper discusses the design aspects of multi-degree of freedom force sensors. Some well-proven mechanical concepts developed at K.U. Leuven are presented. Further, the consequences of using force feedback upon the robot control structure will be discussed.     

Active sensing control improving SLAM accuracy for a vehicle robot

Artificial Life and Robotics - This study considers an autonomous mobile vehicle using SLAM technology in an unknown environment. The focused problem is the decrease of trajectory following...     

Force position control for a robot finger with a soft tip and kinematic uncertainties

We consider the problem of force and position regulation for a robot finger with a soft tip in contact with a surface with unknown geometrical characteristics. An adaptive controller is proposed, and the asymptotic convergence of the applied force error and the estimated position error of the tip to zero is shown for the spatial case. Simulation results demonstrate the controller performance.     

An active sensing strategy for contact location without tactile sensors using robot geometry and kinematics

In this study, we develop new techniques to sense contact locations and control robots in contact situations in order to enable articulated robotic systems to perform manipulations and grasping actions. Active sensing approaches are investigated by utilizing robot kinematics and geometry to improve upon existing sensing methods for contact. Compliant motion control is used so that a robot can actively search for and localize the desired contact location. Robot control in a contact situation is improved by the precise estimation of the contact location. From this viewpoint, we investigate a new control strategy to accommodate the proposed sensing techniques in contact situations. The proposed estimation algorithm and the control strategy both work complementarily. Then, we verify the proposed algorithm through experiments using 7-DOF hardware and a simulation environment. The two major contributions of the proposed active sensing strategy are the estimation algorithm for contact location without any tactile sensors, and the control strategy complementing the proposed estimation algorithm.     

Fuzzy sliding mode control of a finger of a humanoid robot hand

Abstract: The motion control problem for the finger of a humanoid robot hand is investigated. First, the index finger of the human hand is dynamically modelled as a kinematic chain of cylindrical links. During construction of the model, special attention is given to determining bone dimensions and masses that are similar to the real human hand. After the kinematic and dynamic analysis of the model, in order to ensure that the finger model tracks its desired trajectory during a closing motion, a fuzzy sliding mode controller is applied to the finger model. In this controller, a fuzzy logic algorithm is used in order to tune the control gain of the sliding mode controller; thus, an adaptive controller is obtained. Finally, numerical results, which include a performance comparison of the proposed fuzzy sliding mode controller and a conventional sliding mode controller, are presented. The results demonstrate that the proposed control method can be used to perform the desired motion task for humanoid robot hands efficiently.     

A position/force control for a robot finger with soft tip and uncertain kinematics

We consider the position and force regulation problem for a soft tip robot finger in contact with a rigid surface under kinematic and dynamic parametric uncertainties. The reproducing force is assumed to be related to the displacement through a nonlinear function whose characteristics are unknown, but both the actual displacement and force can be directly measured. Kinematic uncertainties concern the rigid surface orientation and the contact point location. Kinematic parameters involved in the contact point location concern the length from the last joint to the contact point and the rest of the link lengths in the general case. An adaptive controller with a composite update parameter law is proposed, and the asymptotic stability of the force and estimated position errors under dynamic and kinematic uncertainties is shown for the planar case. Simulation results for a three‐degrees‐of‐freedom planar robotic finger are presented. © 2002 Wiley Periodicals, Inc.     

一种触觉感知与脑启发的触觉传感系统

触觉智能感知是当前研究的热点问题之一.然而,大规模触觉数据集的缺乏限制了机器人触觉感知领域的发展,解决问题的关键在于构建覆盖手掌的高时空分辨率触觉压力传感器系统.对此,构建一种脑启发的触觉传感系统(BITSS),以高时空分辨率对触觉压力信息进行获取,并实现基于脉冲事件的触觉感知.受皮肤触觉感受器启发,BITSS使用神经形态模型对触感压力信号进行脉冲编码,实现两种触觉感受器神经元的模拟.实验结果表明,BITSS模拟的神经放电活动可以解码出抓握状态的低维空间.在10种日常物体的分类任务中,基于脉冲事件的分类器分类精度达到94%,具有较快的执行速度,并验证了BITSS对触感压力信号的时空编码能力.     

Development of a flexible three-axial tactile sensor array for a robotic finger

In this paper, we propose a flexible three-axial tactile sensor array for measuring both normal and shear loads. The sensor array has 16 tactile sensor units based on piezoresistive strain gauge. It is constructed on a Kapton polyimide film using advanced polymer micromachining technologies. Thin metal strain gauges are embedded in polyimide to measure normal and shear loads, which are tested by applying forces from 0 to 1?N. The developed sensor unit had a hysteresis error of about 9% and repeatability error of about 1.31%. The sensor showed a good resulting image when pressed by a circle-shaped object with 10?N loads. The proposed flexible three-axial tactile sensor array can be applied in a curved or compliant surface that requires slip detection and flexibility, such as a robotic finger.     

Hybrid sensing and encoding using pad phone for home robot control

Multimedia Tools and Applications - For the patients with limb disorder to control the home robot movement, the human intention sensing and encoding are the two important tasks. This paper focuses...     

Robust design and task-priority control for rescue robot HURCULES

This paper proposes a novel design strategy and task-priority-based control methodology for a robot to successfully complete a rescue operation in an extremely unstructured environment. The mechanical structure is designed to obtain both versatile manipulability and all-terrain mobility. The regularized hierarchical quadratic program is used for whole-body motion and force control. The optimization strategy is reasoning about regularization and thus it ensures convergence of the solution in the face of singularities while taking into account equality and inequality constraints. We demonstrate the effectiveness of the online optimization-based control algorithms through extensive real-world numerical and experimental results. Finally, we highlight that the rescue robot can successfully execute missions to extract a casualty and dispose of a dangerous object both indoor and outdoor environments.     

Development of a bioinspired MEMS based capacitive tactile sensor for a robotic finger

This paper presents the development of a MEMS based capacitive tactile sensor intended to be incorporated into a tactile array as the core element of a biomimetic fingerpad. The use of standard microfabrication technologies in realising the device allowed a cost efficient fabrication involving only a few process steps. A low noise readout electronics system was developed for measuring the sensor response. The performance of both bare and packaged sensors was evaluated by direct probing of individual capacitive sensor units and characterising their response to load–unload indentation cycles.     

A multi-purpose dynamic and tactile sensor for robot manipulators

In this article, a multi-purpose tactile/acceleration sensor system made of newly developed thick polymeric piezoelectric material and capable of sensing acceleration, contact force and pressure is developed and evaluated using analytical and experimental techniques, The sensor system is discretized and modeled by a single degree of freedom second order system from which equations of electromechanical dynamics are formulated to evaluate its performance. Analytical solutions are compared favorably with experimental results.     

胶囊机器人无线控制系统设计

介绍一种微型胶囊机器人的无线控制方法,首先分析了人体的生物电磁效应对无线传输的影响,根据其影响关系,选择无线射频芯片nRF905实现无线通信。上位机(PC机)和微控制器间通过USB口进行串行通信,再利用超低功耗微控制器MSP430f1232的SPI口与nRF905进行数据传输,最后在实验室的无线通信实验验证了这种方法的可行性。     

Stability analysis of a vision-based control design for an autonomous mobile robot

We propose a simple control design allowing a mobile robot equipped with a camera to track a line on the ground. The control algorithm, as well as the image-processing algorithm, are very simple. We discuss the existence and the practical stability of an equilibrium trajectory of the robot when tracking a circular reference line. We then give a complementary analysis for arbitrary reference lines with bounded curvature. Experimental results confirm the theoretical analysis.     

机器人控制软件的图形化编程系统设计

提出了一种基于图形化编程的机器人软件系统的总体结构设计,包括软件结构的总体设计思路,主要处理从流程图式的图形化结构到类C语言的转换,再将这种类C语言翻译转换为下位机所能识别的目标代码,经过串口通讯下载到下位机中,完成上位机和下位机的信息交互.提出的设计方法和思路已经过严格的测试和检测,实际应用表明,该系统具有较好的灵活性,稳定性和实用性.     

The development and control of a flexible-spine for a human-form robot

In this paper, the development of a robot which has a flexible spine is presented. By embedding a multi-d.o.f. soft structure into a robot body as a spine, the robot can increase its ability to absorb shock and to work in various environment such as narrow places. As a result of these abilities, the robot can expand its opportunity to work in the human environment. Moreover, its motion could be more natural. The developed full-body human-form robot has a five-jointed flexible spine. Each joint (vertebra) has 3 d.o.f. Between each vertebrae is a 'disk' made of silicone rubber. The spine is controlled by eight tendons, whose tensions can be controlled using tension sensors and locally distributed microcontrollers. This paper describes the development of the flexible spine and the control of the posture of the spine and body.     

Walking-support robot system for walking rehabilitation: design and control

An intelligent walking-assistance robot system has been developed to help the elderly or the disabled in rehabilitation programs. From the design viewpoint, several different mechanisms to satisfy the strict requirements for use in a rehabilitation program were considered and studied. A two-wheel mobile mechanism was developed to provide motions to follow the patient's walking trajectory, and also to make the patient follow a specified trajectory. Equations of motion were derived for the unloading control, and a force control algorithm was developed. For motion control of the mobile base, virtual trajectory planning by the B-spline method and PID control were used. Sensing the motion of the patient is performed by a linear potentiometer and a rotating encoder attached to the robot manipulator. The system was tested on patients in hospital and the experimental results are reported.     

Beat gesture recognition and finger motion control of a piano playing robot for affective interaction of the elderly

This paper introduces a piano playing robot in views of smart house and assistive robot technology to care the affective states of the elderly. We address the current issues in this research area and propose a piano playing robot as a solution. For affective interaction based on music, we first present a beat gesture recognition method to synchronize the tempo of a robot playing a piano with the desired tempo of the user. To estimate the period of an unstructured beat gesture expressed by any part of a body or an object, we apply an optical flow method, and use the trajectories of the center of gravity and normalized central moments of moving objects in images. In addition, we also apply a motion control method by which robotic fingers are trained to follow a set of trajectories. Since the ability to track the trajectories influences the sound a piano generates, we adopt an iterative learning control method to reduce the tracking error.