Further Development of a Robotic-Assisted Transfer Device

Comparison of trunk mechanics and spatiotemporal outcomes in caregivers using a robotic assisted transfer device and a mobile floor lift

OBJECTIVE

The purpose of this study was to compare trunk mechanics, distance covered, and average instantaneous velocity and acceleration recorded with caregivers performing transfer tasks using a research mannequin with both a prototype robotic assisted transfer device (RATD) and a mobile floor lift.

DESIGN

Cross-Sectional.

SETTING

Biomechanics Lab and Human Engineering Research Laboratories.

PARTICIPANTS

Caregivers (N = 21).

INTERVENTION

Robotic Assisted Transfer Device.

OUTCOME MEASURES

Range of flexion-extension, lateral bend, and axial rotation; distance covered; average instantaneous velocity and acceleration.

RESULTS

Caregivers performing transfers using the RATD as compared to when using the moble floor lift reported significantly smaller range of trunk flexion-extension, lateral bending, and axial rotation, and reported lower pelvic based distance covered and slower average instantaneous velocity and acceleration (P < 0.001).

CONCLUSION

The design and usability of a RATD indicates design driven mobility advantages over clinical standard mobile floor lifts due to its ability to expand the workspace while further reducing risk factors for low back pain. While the concept is promising, further testing is required to address limitations and confirm the concept for clinical applications.

Lauren M, Cooper R, Bendixen R, Koontz AM, Cooper RA. Clinical and Ergonomic Comparison Between a Robotic Assisted Transfer Device and a Mobile Floor Lift During Caregiver-Assisted Wheelchair Transfers

BACKGROUND

The robotic assisted transfer device was developed as an updated lift technology to reduce adjustments in posture while increasing capabilities offered by transfer devices. The purpose of this study was to compare the trunk biomechanics of a robotic assisted transfer device and a mechanical floor lift in the transfer of a care recipient by a caregiver during essential transfer tasks.

METHODS

Investigators enrolled 28 caregiver/care recipient dyads to complete 36 transferring tasks. Surface electromyography for the back muscles and motion data for trunk range of motion were collected for selected surfaces, phase, and direction tasks using a robotic assisted transfer device and a mechanical floor lift.

RESULTS

Robotic assisted transfer device transfers required significantly smaller range of trunk flexion (P < 0.001), lateral bend (P < 0.001), and axial rotation (P = 0.01), in addition to smaller distance covered (P < 0.001), average instantaneous velocity (P = 0.01), and acceleration (P < 0.001) compared with a mobile floor lift. The robotic assisted transfer device transfers required significantly smaller peak erector spinae (left: P = 0.001; right: P < 0.001) and latissimus dorsi (right: P < 0.001) and integrated erector spinae left (P = 0.001) and latissimus dorsi right (P = 0.01) electromyography signals compared with the floor lift.

CONCLUSIONS

The robotic assisted transfer device provides additional benefits to mobile floor lifts which, coupled with statistically lower flexion, extension, and rotation, may make them an appealing alternative intervention.

Assessment of Muscle Activation of Caregivers Performing Dependent Transfers With a Novel Robotic-Assisted Transfer Device Compared With the Hoyer Advance

OBJECTIVE

The purpose of this study was to compare muscle activity in caregivers while using a novel robotic-assisted transfer device (Strong Arm) to a clinical standard of care (Hoyer Advance).

DESIGN

A quasi-experimental design was used in which 20 caregivers (33 ± 15 yrs old) performed transfers with three surfaces (toilet, bench, and shower chair) with the Strong Arm and Hoyer Advance. Transfer completion time (seconds), peak percentage surface electromyography (EMG), and integrated EMG of the bilateral erector spinae, latissimus dorsi, pectoralis major and anterior deltoid were measured.

RESULTS

Caregivers required less transfer time when transferring from wheelchair to surface using the Hoyer Advance (P = 0.011, f = 0.39). For the lower back, significantly lower peak percentage EMGs were found using Strong Arm in 50% and for the integrated EMG in 25% of the cases, with the remaining cases showing no significant differences. For the shoulder, significantly lower peak percentage EMG values were found using Strong Arm in 19% of transfers and lower integrated EMG was found in 25% of transfers when using the Hoyer Advance, with the remaining cases showing no significant differences.

CONCLUSION

Although back muscle activation during Strong Arm transfers is statistically, but not clinically, lower, additional features that couple with significantly lower muscle activation make it an alternative to the clinical standard for further research and possible clinical applicability.

Development of Transfer-Assisting Robot System Using Posture-Supporting Wear and Support Robot

When assisting a care receiver to transfer from one plane to another, a caregiver needs to hold up and move him/her. As a caregiver has to support the weight of one person, transfer assistance imposes a heavy physical burden on the caregiver. Particularly, in Japan, with an increasing elderly population and a decreasing young population, there are a few caregivers to assist numerous care receivers to transfer. In this scenario, it is an extremely vital issue to develop methods to reduce the burden of the caregivers when assisting care receivers to transfer. In this study, by focusing on the clothes that care receivers wear, we developed a transfer-assisting robot system by combining a dedicated posture-supporting wear and a mobile robot based on a lift mechanism.

Usability and task load comparison between a robotic assisted transfer device and a mechanical floor lift during caregiver assisted transfers on a care recipient

INTRODUCTION

The RATD represents a novel methodology to reduce strain, manoeuvring, and cognitive load a caregiver experiences when conducting transfers on a mannequin. However, caregivers who used this new technology report suggested adjustments regarding the robot's human machine interface and shape as to improve transfer efficiency and comfort for care recipients. The purpose of this study was to test a redesigned RATD and compare its ergonomics during a transfer to those of a mechanical floor lift.

METHODS

This was cross sectional protocol. As opposed to prior research which used a mannequin, caregivers in this study (N = 28) partnered with, and transferred, a mobility device user (N = 28) at three unique surfaces. Information about task demand and usability was collected from surveys after use of each device at each surface.

RESULTS

Results indicated reduced physical demand (p = .004) and discomfort frequency (p = .01) in caregivers conducting the transfers with the RATD compared to the mechanical floor lift. Care recipients reported no significant differences between both transfer devices. Critiques with the interface, the harness and sling, and the robot's rigidity indicated more work is needed before introducing this technology to a larger market. Conclusions: The RATD represents a promising new intervention for transferring and handling care recipients who use wheelchairs. However, while caregivers report reduced physical demand and discomfort, more work is required to advance the ease of the human machine interface, the amount of space allowed for the robot to operate, and the ability of the care recipient to operate the technology independently.IMPLICATIONS FOR REHABILITATIONCaregivers report significant physical and mental stress while transferring clients in and out of a wheelchair.Clinical standard transfer equipment is limited in the space which it can be used.Robots, particularly those portable and powered, have the ability to not only make the transfer experience safer, but also expand the applications this equipment can provide.

Person transfer assist systems: a literature review

OBJECTIVE

Novel developments in the robotics field have produced systems that can support person wheelchair transfers, maximize safety and reduce caregiver burden. The purpose of this study was to identify and describe these systems, their usability (or satisfaction), the context for which they have been or can be used and how they have been evaluated to determine evidence for their effectiveness.

METHOD

Available research on Person Transfer Assist Systems (PTAS) was systematically gathered using similar standards to the PRISMA guidelines. The search terms were derived from common terms and via exploring similar review articles. Initial search terms displayed 1330 articles and by using the inclusion/exclusion criteria 96 articles were selected for abstract review. After full- text reviewing 48 articles were included.

RESULTS

29 articles concerned research in robotic transfer systems, 10 articles used both ceiling and floor-mounted lifts and 9 articles used only floor-mounted lifts as an intervention/control group. The results of this analysis identified a few usability evaluations for robotic transfer prototypes, especially ones comparing prototypes to existing marketed devices.

CONCLUSION

Robotic device research is a recent development within assistive technology. Whilst usability evaluations provided evidence that a robotic device will provide better service to the user, the sample number of subjects used are minimal in comparison to any of the intervention/control group articles. Experimental studies between PTASs are required to support technological advancements. Caregiver injury risk has been the focus for most of the comparison articles; however, few articles focus on the implications to the person.IMPLICATIONS FOR REHABILITATIONCeiling mounted lifts are preferred over floor-based lifts due to lower injury rates.Many robotic transfer systems have been developed; however, there is a paucity of quantitative and qualitative studies.Based on the results of this review, rehabilitation settings are recommended to use ceiling over floor assist systems, and it is recommended to provide training on using devices to assist with patient transfers to lower the risk of injuries.

Lateral Transfer Assist Robot (LTAR): Development of a proof-of-concept prototype

BACKGROUND

Falls during transfer to and from a wheelchair are associated with numerous problems. Factors responsible for difficulty in transferring include horizontal/vertical gaps between surfaces; obstacles, such as armrests; and complicated brake/footrests configurations before transferring. Moreover, controlling a wheelchair sufficiently close to the transfer surface within the confined home space is difficult.

OBJECTIVE

We described the design of the novel Lateral Transfer Assist Robot (LTAR) for solving problems during transfer. Furthermore, the effectiveness and usability of the robot were preliminary examined in healthy adults.

METHOD

The transfer problems and basic designs were organized. The effectiveness of the prototype was measured by three-dimensional motion analysis and questionnaire.

RESULTS

The prototype LTAR was developed. With just a push on a button, the footplate lowers to the floor and the seat and armrest lowers to the height of the seating surface to fill the gap between the surfaces. Using these features, users can transfer by simply shifting their buttocks sideways. Additionally, LTAR has omnidirectional wheels that help move it within a narrow space. The LTAR was confirmed to reduce the physical and subjective burden, except for maneuverability.

CONCLUSION

The LTAR was found to be effective for home use and reducing burden of transfer.

Assessment of Usability and Task Load Demand Using a Robot-Assisted Transfer Device Compared With a Hoyer Advance for Dependent Wheelchair Transfers

OBJECTIVE

Manual lifting can be burdensome for people who care for power wheelchair users. Although technologies used for dependent transfers are helpful, they have shortcomings of their own. This study compares the usability and task load demand of a novel robot-assisted transfer device to a clinical standard when performing dependent transfers.

DESIGN

A cross-sectional study was conducted to assess caregivers (N = 21) transferring a 56-kg mannequin with the Strong Arm and Hoyer Advance at three transfer locations. Feedback was gathered through qualitative surveys.

RESULTS

Usability was significant in multiple areas important for transfers. Caregiver fatigue and discomfort intensity were reduced, and the Strong Arm was preferred at the three transfer locations. Device ease and efficiency favored Strong Arm at two stations as was discomfort frequency. In addition, physical demand, frustration, and effort were significantly lower using Strong Arm compared with the Hoyer Advance.

CONCLUSIONS

Compared with the Hoyer, participants favored Strong Arm for transfer usability and task load demand. However, further Strong Arm developments are needed.