TY - JOUR T1 - Design of a haptic arm exoskeleton for training and rehabilitation JF - IEEE/ASME Transactions on Mechatronics Y1 - 2006 A1 - Abhishek Gupta A1 - O'Malley, M.K. KW - Damping KW - Degrees of freedom (mechanics) KW - Joints (anatomy) KW - Patient rehabilitation KW - Robot applications KW - Sensory perception KW - Stiffness AB -

A high-quality haptic interface is typically characterized by low apparent inertia and damping, high structural stiffness, minimal backlash, and absence of mechanical singularities in the workspace. In addition to these specifications, exoskeleton haptic interface design involves consideration of space and weight limitations, workspace requirements, and the kinematic constraints placed on the device by the human arm. These constraints impose conflicting design requirements on the engineer attempting to design an arm exoskeleton. In this paper, the authors present a detailed review of the requirements and constraints that are involved in the design of a high-quality haptic arm exoskeleton. In this context, the design of a five-degree-of-freedom haptic arm exoskeleton for training and rehabilitation in virtual environments is presented. The device is capable of providing kinesthetic feedback to the joints of the lower arm and wrist of the operator, and will be used in future work for robot-assisted rehabilitation and training. Motivation for such applications is based on findings that show robot-assisted physical therapy aids in the rehabilitation process following neurological injuries. As a training tool, the device provides a means to implement flexible, repeatable, and safe training methodologies. © 2006 IEEE.

VL - 11 UR - http://dx.doi.org/10.1109/TMECH.2006.875558 N1 -

Arm exoskeletons;Apparent inertia;Design methodology;

ER - TY - JOUR T1 - The effect of virtual surface stiffness on the haptic perception of detail JF - IEEE/ASME Transactions on Mechatronics Y1 - 2004 A1 - O'Malley, M.K. A1 - Michael Goldfarb KW - Computer aided design KW - Computer hardware KW - Computer simulation KW - Degrees of freedom (mechanics) KW - Manipulators KW - Object recognition KW - Sensory perception KW - Specifications KW - Stiffness KW - Surface properties KW - Virtual reality AB -

This brief presents a quantitative study of the effects of virtual surface stiffness in a simulated haptic environment on the haptic perception of detail. Specifically, the haptic perception of detail is characterized by identification, detection, and discrimination of round and square cross section ridges. Test results indicate that performance, measured as a percent correct score in the perception experiments, improves in a nonlinear fashion as the maximum level of virtual surface stiffness in the simulation increases. Further, test subjects appeared to reach a limit in their perception capabilities at maximum stiffness levels of 300 to 400 N/m, while the hardware was capable of 1000 N/m of maximum virtual surface stiffness. These results indicate that haptic interface hardware may be able to convey sufficient perceptual information to the user with relatively low levels of virtual surface stiffness. © 2004 IEEE.

VL - 9 UR - http://dx.doi.org/10.1109/TMECH.2004.828625 N1 -

Virtual surface stiffness;Haptic perception;Design specifications;Haptic interface hardware;

ER -