The control of exploratory and manipulative procedures in teleoperation and virtual environments requires the availability of adequate advanced interfaces capable not only of recording the movements of the human hands and arms, but also of replicating sensations of contact and collisions. In this paper the problem of replicating external forces acting against the remote/virtual arm is addressed. The design of an arm exoskeleton system developed in the authors’ laboratory is presented. The exoskeletonconsists of a 7 DOF actuated and sensorized mechanical structure wrapping up completely the human arm and directly supported by the shoulders and the trunk of the human operator. Emphasis is given to the implemented control procedures and to the description of the transputer-based control architecture.

(далее…)

Категория: Научные статьи | Нет комментариев »

An exoskeleton system is being developed to aid in the mobilization of walking-impaired patients. New approaches to personal robotic assists have solved many classic problems with weight, power, endurance, and cost. A versatile platform of development allows for many variations and applications including mobility assist for the paralyzed, amputee, and spastic patient (MAPAS). A variety of strap on supports and braces are used, depending on the magnitude of the forces required. The MAPAS system utilizes compressed gas to power the main force producing elements, or muscles. Pneumatic muscles are used to provide controllable joint torque with moderate levels of pressure. These muscles are mounted to the brace, providing pull-only torque to joints. The MAPAS control system features interpreted joint mapping. The function of each leg joint is primarily directed through the output of a finger joint sensor. A six to eight sensor hand goniometer provides the system with user input. Higher control features actuated by on-board intelligent devices enable finger joint inputs to be enhanced providing balance, gait anticipation, fault-recovery, and spasm signature compensation. Ambient pressure levels of on-board reservoirs can be changed to suit changing environments ranging from heavily loaded amputee walking up stairs to the slight correction of a mild spasm. The entire system is portable with on-board batteries, compressed air reservoirs, intelligent algorithms, and goniometric sensors.

(далее…)

Категория: Научные статьи | Нет комментариев »

The development of haptic systems for VR and telepresence has been identified as a key feature in the progression from observation of the environment to interaction. Arm masters and exoskeletons have formed an important user interface for the provision of such facilities, with these devices requiring a subtle combination of complex mechanical, electrical and kinematic structures with user requirements of low mass, portability, comfort, flexibility and safety. The actuation system is often identified as a focus of this design blending process. This work considers the design, construction and testing of a light weight comfortable high power 7 degree of freedom force feedback exoskeleton. This is achieved through the use, modeling and control of pneumatic muscle actuators (pMA) that provide lightweight, low cost, flexible, portable, comfortable and inherently safe input/feedback/control operation. Models of operation in a virtual environment are developed and demonstrated, with experimental results to illustrate the effectiveness of the device in replicating contact forces and creating a sensation of virtual presence.

(далее…)

Категория: Научные статьи | Нет комментариев »

In this paper, a novel material handling system is presented. An overview of the hardware is provided, and issues related to control of the arms are discussed. It is believed that when it is completed, use of this material handling system will help reduce or eliminate workplace back injuries due to repetitive lifting.

(далее…)

Категория: Научные статьи | Нет комментариев »

The design of a bilateral (force-reflecting) exoskeleton with kinesthetic feedback is discussed. The design process was hindered by a lack of fundamental biodynamic data, which had to be synthesized from other studies. Areas of human performance research are identified to verify the biodynamic assumptions made during this project. Areas of manipulation research, using a kinematically redundant slave robot, are described to quantify the expected improvements in telemanipulation resulting from the kinesthetic feedback provided by this exoskeleton.

(далее…)

Категория: Научные статьи | Нет комментариев »