Evaluation by Expert Dancers of a Robot That Performs Partnered Stepping via Haptic Interaction

PLOS ONE, Dec 2019

Our long-term goal is to enable a robot to engage in partner dance for use in rehabilitation therapy, assessment, diagnosis, and scientific investigations of two-person whole-body motor coordination. Partner dance has been shown to improve balance and gait in people with Parkinson's disease and in older adults, which motivates our work. During partner dance, dance couples rely heavily on haptic interaction to convey motor intent such as speed and direction. In this paper, we investigate the potential for a wheeled mobile robot with a human-like upper-body to perform partnered stepping with people based on the forces applied to its end effectors. Blindfolded expert dancers (N=10) performed a forward/backward walking step to a recorded drum beat while holding the robot's end effectors. We varied the admittance gain of the robot's mobile base controller and the stiffness of the robot's arms. The robot followed the participants with low lag (M=224, SD=194 ms) across all trials. High admittance gain and high arm stiffness conditions resulted in significantly improved performance with respect to subjective and objective measures. Biomechanical measures such as the human hand to human sternum distance, center-of-mass of leader to center-of-mass of follower (CoM-CoM) distance, and interaction forces correlated with the expert dancers' subjective ratings of their interactions with the robot, which were internally consistent (Cronbach's α=0.92). In response to a final questionnaire, 1/10 expert dancers strongly agreed, 5/10 agreed, and 1/10 disagreed with the statement "The robot was a good follower." 2/10 strongly agreed, 3/10 agreed, and 2/10 disagreed with the statement "The robot was fun to dance with." The remaining participants were neutral with respect to these two questions.

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Evaluation by Expert Dancers of a Robot That Performs Partnered Stepping via Haptic Interaction

May Evaluation by Expert Dancers of a Robot That Performs Partnered Stepping via Haptic Interaction Tiffany L. Chen 0 1 Tapomayukh Bhattacharjee 0 1 J. Lucas McKay 0 1 Jacquelyn E. Borinski 0 1 Madeleine E. Hackney 0 1 Lena H. Ting 0 1 Charles C. Kemp 0 1 0 1 Department of Biomedical Engineering, Georgia Institute of Technology , Atlanta, GA , USA , 2 Department of Biomedical Engineering, Emory University School of Medicine , Atlanta, GA , USA , 3 Department of Medicine, Emory University School of Medicine , Atlanta, GA , USA , 4 Department of Medicine, Atlanta VA Geriatric Research Education and Clinical Center , Atlanta, GA , USA 1 Academic Editor: Catalin Buiu, Politehnica University of Bucharest , ROMANIA Our long-term goal is to enable a robot to engage in partner dance for use in rehabilitation therapy, assessment, diagnosis, and scientific investigations of two-person whole-body motor coordination. Partner dance has been shown to improve balance and gait in people with Parkinson's disease and in older adults, which motivates our work. During partner dance, dance couples rely heavily on haptic interaction to convey motor intent such as speed and direction. In this paper, we investigate the potential for a wheeled mobile robot with a human-like upper-body to perform partnered stepping with people based on the forces applied to its end effectors. Blindfolded expert dancers (N=10) performed a forward/ backward walking step to a recorded drum beat while holding the robot's end effectors. We varied the admittance gain of the robot's mobile base controller and the stiffness of the robot's arms. The robot followed the participants with low lag (M=224, SD=194 ms) across all trials. High admittance gain and high arm stiffness conditions resulted in significantly improved performance with respect to subjective and objective measures. Biomechanical measures such as the human hand to human sternum distance, center-of-mass of leader to center-of-mass of follower (CoM-CoM) distance, and interaction forces correlated with the expert dancers' subjective ratings of their interactions with the robot, which were internally consistent (Cronbach's =0.92). In response to a final questionnaire, 1/10 expert dancers strongly agreed, 5/10 agreed, and 1/10 disagreed with the statement "The robot was a good follower." 2/10 strongly agreed, 3/10 agreed, and 2/10 disagreed with the statement "The robot was fun to dance with." The remaining participants were neutral with respect to these two questions. - Funding: Funding was provided by the NSF Graduate Research Fellowship Program (GRFP), and National Science Foundation EFRI-M3C: Partnered Rehabilitative Movement: Cooperative Human-Robot Interactions for Motor Assistance, Learning, and Communication Award #: 1137229, MH LT CK (http://www.nsf.gov/awardsearch/showAward? AWD_ID=1137229&HistoricalAwards = false). The funders had no role in study design, data collection Competing Interests: The authors have declared that no competing interests exist. Partner dance is an effective rehabilitation intervention that relies heavily on haptic interaction between individuals. By haptic interaction, we mean any interaction through the sense of touch. Partner dance has been shown to improve balance, gait, functional mobility, and functional autonomy in people with Parkinsons disease (PD) [13]. Participants undergoing partner dance therapy expressed enjoyment, satisfaction, improved well-being, and interest in continuing the therapy [2]. In partner dance, such as waltz, foxtrot, and tango, partners communicate haptically through constant physical contact in order to generate coordinated, whole-body motion. This contact is made via a configuration of their hands and arms called their frame. Effective communication is crucial to the interaction since partner dance is often improvised without a set sequence of steps [4], and evidence suggests that haptic information can be sufficient to perform partner dance with complicated movements [5, 6]. As such, partner dance may serve as a useful paradigm for scientific inquiry into physical human-human interaction [7]. Robots may be able to play beneficial roles in partner dance therapy, such as serving as dance partners, performing assessments of participants, and acting as scientific instruments with which to conduct research. Robots for upper and lower extremity rehabilitation have successfully performed comparable roles, from helping people recover function [810] to performing diagnostic assessments [11]. In this paper, we investigate the potential for a mobile manipulator with a wheeled base and compliant arms to perform a simple dance with a person. Specifically, in our study, the robot serves as the follower and the human as the leader in a partnered step during which the human walks backwards and forwards to a recorded drum beat while holding the robots end effectors. The robot, Cody, is a general purpose robot that was not specifically des (...truncated)


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Tiffany L. Chen, Tapomayukh Bhattacharjee, J. Lucas McKay, Jacquelyn E. Borinski, Madeleine E. Hackney, Lena H. Ting, Charles C. Kemp. Evaluation by Expert Dancers of a Robot That Performs Partnered Stepping via Haptic Interaction, PLOS ONE, 2015, Volume 10, Issue 5, DOI: 10.1371/journal.pone.0125179