Research Projects

The primary goal of this research effort is to improve the effectiveness of skill transfer, rehabilitation, and collaboration via haptic devices. To do so, we will formulate requirements for shared control between humans and robots in haptic systems designed for training, rehabilitation, and collaboration. Experimental test-beds comprised of one and two commercial haptic devices with force sensing capabilities is employed throughout the project. We plan to study two shared control system architectures for skill transfer. In the first, the human acts as the novice or patient, and the robot serves as the expert. Control schemes for the expert system (the haptic device) will be designed and analyzed theoretically and experimentally. The second phase of the research effort will explore human-robot-human interfaces.

Our goals in this research project are to determine the significance of performance of inanimate tasks as a marker for robotic proficiency and assess the utility of inanimate task training on robotic skill performance.  We aim to establish standardized tasks for training, define accurate metrics for performance, and assess motor skill acquisition in virtual and real environments.

Robot-assisted surgery offers distinct advantages and is rapidly being applied to a diverse range of surgical procedures.  However, teleoperation inherently decouples the surgeon from the patient.  While robotic-assistance permits a more natural, intuitive interface in comparison to standard laparoscopy, there is still a significant learning curve in mastering the technique.  In addition, the advantages of the robotic system are further limited by the lack of tactile and kinesthetic information transmitted to the surgeon.  Given this lack of sensory feedback, more emphasis is placed on interpreting visual cues and understanding robotic movement during performance.

Virtual fixtures, shared controllers and other haptic guidance schemes have been supplement with virtual motor tasks in order to improve performance and skill retention and to reduce training duration and user workload. In an error-reducing shared controller implemented in our lab, the performance of a manual task was influenced by participants’ ability to identify and then excite a virtual two-mass system at the natural frequency of the system. In a series of experiments, we explore if parameters of the dynamic system influence human perception as well as increase the rate of task performance.

Vibrating muscle tendons at a range of frequencies is known to produce movement illusions in human subjects. Although there are examples in the literature on the use of vibrators to transmit simple cues such as direction information, movement illusions due to vibration have not been utilized as a method of providing illusory kinesthetic feedback. One possible main application is artificial proprioception for prosthetic devices.

Although it is relatively easy to induce the illusion, it is difficult to generate controlled sensations due to the inconsistency and instability of the illusion, differences observed among subjects, muscle configuration, and load conditions, among other reasons.