Search

Traditional teleoperation (leader/follower) systems primarily focus on one operator controlling one remote robot, but as robots become ubiquitous, there is an increasing need for multiple operators, including autonomous agents, to collaboratively control multiple robots. However, existing teleoperation frameworks do not inherently support the variety of possible collaborations, such as multiple operators, each with an input device (leader), controlling a robot and camera or different degrees of freedom of a single robot (follower). The same concept applies to teleoperating robots in a simulation environment through physical input devices. In this letter, we extend our novel simulation framework that is capable of incorporating multiple input devices asynchronously with a real-time dynamic simulation to incorporate a customizable shared control. For this purpose, we have identified and implemented a sufficient set of coordinate frames to encapsulate the pairing of multiple leaders, followers and cameras in a shared asynchronous manner with force feedback. We demonstrate the utility of this framework in accelerating user training, ease of learning, and enhanced task completion times through shared control by a supervisor.

The development of powered hand orthoses and exoskeletons for treatment of chronic motor deficits due to stroke, traumatic brain injury, and cerebral palsy has been widely explored by the robotics engineering community. The conditions arising from these disorders take several forms and clinical descriptions of the various deficits are at times difficult to interpret for those with limited interaction with patients. With devices commonly designed and evaluated on their ability to aid hand closure, well-known extension deficits that are present among these patients typically receive only secondary consideration by robotic approaches. Quantitative characterization of these extension deficits in a manner that is easily translated into engineering design criteria would greatly benefit device design and evaluation. Here, we measure the externally applied torques required to assist extension of the index finger and thumb of three patients with increased flexor tone in the hand. The average torque required to fully extend a subject's index finger MCP joint ranged from 0.22 - 0.75 N·m and the thumb's MCP from 0.29 - 1.35 N·m. The highest torques were recorded when subjects were asked to volitionally extend their fingers, causing an increase in flexor tone requiring more assistance to overcome than when they were relaxed.

Enabling individuals who are living with reduced mobility of the hand to utilize portable exoskeletons at home has the potential to deliver rehabilitation therapies with a greater intensity and relevance to activities of daily living. Various hand exoskeleton designs have been explored in the past, however, devices have remained nonportable and cumbersome for the intended users. Here we investigate a remote actuation system for wearable hand exoskeletons, which moves weight from the weakened limb to the shoulders, reducing the burden on the user and improving portability. A push-pull Bowden cable was used to transmit actuator forces from a backpack to the hand with strict attention paid to total system weight, size, and the needs of the target population. We present the design and integration of this system into a previously presented hand exoskeleton, as well as its characterization. Integration of remote actuation reduced the exoskeleton weight by 56% to 113g without adverse effects to functionality. Total actuation system weight was kept to 754g. The loss of positional accuracy inherent with Bowden cable transmissions was compensated for through closed loop positional control of the transmission output. The achieved weight reduction makes hand exoskeletons more suitable to the intended user, which will permit the study of their effectiveness in providing long duration, high intensity, and targeted rehabilitation as well as functional assistance.