Haptic feedback for interactive AR/VR systems: comparing single- vs. dual-muscle EMS for weight perception

Virtual Reality, vol. 29

Abstract

Abstract While electrical muscle stimulation (EMS) shows promise for augmenting weight perception in interactive systems, a clear understanding of how different stimulation strategies affect both the intensity and realism of perceived weight is lacking, particularly concerning the synergistic activation of multiple muscles. This study uniquely addresses this gap by systematically investigating the effects of single-muscle (triceps brachii) versus dual-muscle (triceps brachii and extensor carpi ulnaris) EMS on subjective weight perception. Seventy-five participants (58 male, 17 female, average age 24.9 ± 3.4 years) underwent a three-part within-subject experiment, including calibration of motor and pain thresholds, comparing perceived weights under these two EMS conditions while holding a 2 kg object, direct comparison with a 3 kg physical weight, and exposure to randomized EMS amplitudes. Our key finding and primary contribution is the quantitative demonstration that dual-muscle EMS, incorporating the forearm’s extensor carpi ulnaris, not only elicits a significantly greater increase in perceived weight compared to single-muscle triceps stimulation but also, crucially, enhances the perceived realism of the sensation. This distinction provides important evidence for the benefits of multi-muscle stimulation strategies in creating convincing haptic experiences. These results offer significant implications for designing more effective EMS-based feedback in virtual/augmented reality, rehabilitation, teleoperation and prosthetics, where realistic weight perception is paramount.

Authors 5

1. Apostolos Vrontos corresponding Aachen Institute of Industrial Engineering and Ergonomics

   RWTH Aachen University

   Affiliation as printed

   Institute of Industrial Engineering and Ergonomics, RWTH Aachen University, 52062, Aachen, Germany

2. Reza Zolnouri Aachen Institute of Industrial Engineering and Ergonomics

   RWTH Aachen University

   Affiliation as printed

   Institute of Industrial Engineering and Ergonomics, RWTH Aachen University, 52062, Aachen, Germany

3. Alexander Mertens Aachen Institute of Industrial Engineering and Ergonomics

   RWTH Aachen University

   Affiliation as printed

   Institute of Industrial Engineering and Ergonomics, RWTH Aachen University, 52062, Aachen, Germany

4. Verena Nitsch Aachen Institute of Industrial Engineering and Ergonomics

   RWTH Aachen University

   Affiliation as printed

   Institute of Industrial Engineering and Ergonomics, RWTH Aachen University, 52062, Aachen, Germany

5. Christopher Brandl Aachen Institute of Industrial Engineering and Ergonomics

   Fraunhofer Institute for Communication, Information Processing and Ergonomics · RWTH Aachen University

   Affiliation as printed

   Fraunhofer Institute for Communication, Information, Processing and Ergonomics FKIE, 52074, Aachen, Germany

   Institute of Industrial Engineering and Ergonomics, RWTH Aachen University, 52062, Aachen, Germany