The purpose of this study is to improve the control performance of radial piston type and vane type pneumatic motors and to investigate whether they can be used in a high-accuracy control system. In this paper, we consider the stabilizing and swinging up control system of a double-inverted pendulum as a high-accuracy control system. Firstly, some basic characteristics of the pneumatic drive, consisting of a pneumatic motor and a control valve, were investigated. Secondly, digital controllers for stabilizing and swinging up were designed taking into consideration the time lag of the pneumatic driving part. As a result, these controllers could stabilize a double-inverted pendulum and could swing up and stabilize a single-inverted pendulum well, with both types of pneumatic motor.
Summary form only given as follows. This paper presents how the control performance of the feature-based visual servo system is improved by utilizing redundant features. Effectiveness of the redundant features is evaluated by the smallest singular value of the image Jacobian which is closely related to the accuracy in the world coordinate system. An LQ control scheme is used to resolve the controllability problem. Usefulness of the redundant features is verified by the real time experiments on a PUMA 560 manipulator.
This study has developed a power assist wear for knee joint. To construct a light weight and soft power assist device, a pneumatic rubber artificial muscle is used as an actuator. This paper shows the structure and operation of the device. Some experimental results illustrate the availability of the developed power assist wear.
In this paper, the authors aim at developing a wearable power assist wear for lower limb The system requires compact size and lightweight to achieve a practical application, therefore we discuss its effective structure using biarticular muscle. At first, two model of targeting at support device for human lower limb is described, followed by showing each alignment of rubber artificial muscles. Next, construction force generated by rubber artificial muscles to achieve static balance is calculated. At the end, Experiment apparatus is designed from calculation and experimental results is showed.
As for a wearable device, it is required that it is small, is light, and be flexible from the viewpoint of the human fnendliness. The pneumatic rubber artificial muscle is useiiil as Ihe actuator that satisfied these demands. In this study, the power assist wears driven wWi a thin seat nibber artificial muscle are newly developed to attempt the making to cc^ripad, and the assist of elbow, wrist and forearm.
To apply a pneumatic actuator more effectively in various automation systems, a pneumatic servo technology should be developed. Recently, from such a viewpoint, the effects of some advanced control strategies as an optimal control or an adaptive control have been confirmed. However, they seem to need some time until put into practical use because of their relatively complicated control algorithms. From the practical application of view, it should be as simple as possible.In this paper, we take notice of the simplicity of a posicast control and propose an advanced posicast control scheme with learning funcion to execute the self tuning. First, we describe the typical features of proposed control scheme. Next, we apply it to the positioning and force control of a pneumatic servo system comprising a pneumatic cylinder and electro-pneumatic proportional control valves. The following is experimentally confirmed.1) The addition of learning function to the original posicast control scheme allows a finite time settling step response even in a certain degree of high order system such as a pneumatic system. Moreover, it is considered to allow the system to adapt to the change in system parameters, the control input saturation and so on.2) The proposed control scheme can attain the higer speed and more accurate positioning and force control compared with an usual PI control scheme, so it is well available to a pneumatic servo control.Generally, a posicast control may be effective for a low damping system such as a pneumatic servo, because it basically utilizes a oscillation property of the controlled system.
To apply a pneumatic robot to not only conventional simple tasks but also more rigorous ones, a servo type control is required. Since it has some high nonlinear properties, some type of adaptive control strategy should be adopted to improve its conrol performance. In this kind of robot, the simplicity of control algorism is also important.In this study, an adaptive variable structure control scheme is developed on the basis of the well-known variable structure system theory. This control scheme confines a phase-plane trajectory on the switching line momentarily rotated adaptively to the phase-state of controlled system. It can suppress the chattering often encountered in the usual sliding mode control with a fixed switching line, to achieve a smooth response. Further, it can automatically generate the specified phase-plane trajectory heading toward the desired position asymptotically.As a result of the application to the PTP type position control of an articulated pneumatic robot, the expected control performance can be well attained. Some advantages of this control method are the simplicity of a control algorism and the flexibility in the decision of control parameter values. Its availability may be verified.
