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A novel wheelchair called PURE ( Personalized Unique Rolling Experience) that uses hands hands-free (HF) torso leanlean-to -steer control has been developed for manual wheelchair users (mWCUs). PURE addresses limitations of current wheelchairs, such as the in ability to use both hands for life experiences instead of propulsion. PURE uses a ball ball-based robot drivetrain to offer a compactcompact, selfself- balancing , omnidirectional mobile device. A custom sensor system convertconverts rider torso motions into direction and speed commands to control PURE, which is especially useful if a rider has minimal torso range of motion. We explored whether PURE’s HF control performed as well as a traditional joystick (JS) human human- robot interface and mWCUsmWCUs, performed as well as able able-bodied users (ABUs). 10 mWCUs and 10 ABUs were trained and tested to drive PURE through courses replicating indoor settingssettings. Each participant adjusted ride sensitivity settings for both HF and JS control . Repeated Repeated-measures MANOVA tests suggested that the number of collisions collisions, completion time time, NASA TLX scores except physical demand , and index of performance performances were similar for HF and JS control and between mWCUs and ABUs for all sections. Th is suggestsuggests that PURE is effective for controlling this new omnidirectional wheelchair by only using torso motion thus leaving both hands to be used for other tasks during propulsion propulsion.
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Hands-Free Physical Human-Robot Interaction and Testing for Navigating a Virtual Ballbot
A hands-free (HF) lean-to-steer control concept that uses torso motions is demonstrated by navigating a virtual robotic mobility device based on a ball-based robotic (ballbot) wheelchair. A custom sensor system (i.e., Torso-dynamics Estimation System (TES)) was utilized to measure and convert the dynamics of the rider’s torso motions into commands to provide HF control of the robot. A simulation study was conducted to explore the efficacy of the HF controller compared to a traditional joystick (JS) controller, and whether there were differences in performance by manual wheelchair users (mWCUs), who may have reduced torso function, compared to able-bodied users (ABUs). Twenty test subjects (10 mWCUs + 10 ABUs) used the subject-specific adjusted TES while wearing a virtual reality headset and were asked to navigate a virtual human rider on the ballbot through obstacle courses replicating seven indoor environment zones. Repeated measures MANOVA tests assessed performance metrics representing efficiency (i.e., number of collisions), effectiveness (i.e., completion time), comfort (i.e., NASA TLX scores), and robustness (i.e., index of performance). As expected, more challenging zones took longer to complete and resulted in more collisions. An interaction effect was observed such that ABUs had significantly more collisions using JS vs. HF control, while mWCUs had little difference with either interface. All subjects reported greater physical demand was needed for HF control than JS control; although, no users visibly showed or expressed fatigue or exhaustion when using HF control. In general, HF control performed as well as JS control, and mWCUs performed similarly to ABUs.
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- Award ID(s):
- 2024905
- PAR ID:
- 10548504
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 979-8-3503-3670-2
- Page Range / eLocation ID:
- 556 to 563
- Format(s):
- Medium: X
- Location:
- Busan, Korea, Republic of
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/RO-MAN57019.2023.10309327
