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

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.

Mechanics Model-Based Motion Design for a Piggyback Nursing-Care Robot

To conduct a comfortable lift for the care-receiver, it takes a lot of time and operations to design the motion trajectory for each care-receiver before transfer tasks. To solve this problem, this paper proposed a method to design a lift trajectory for a piggyback transfer robot. The robot, which can lift and move a person from a wheelchair to a bed or a pedestal pan, has been developed. The trajectory obtained by this method could make the robot conduct a comfort lift for the care-receiver, according to the weight and height of the care-receiver. A human-robot mechanics model and the relationship between the comfortable lift trajectory and the care-receiver’s weight and height were also contributed. According to the test results of 20 subjects, the force parameters used for trajectory design were determined, and the trajectory design method was optimized. The results of three subjects demonstrated that this method could conveniently and quickly provide a robot lift trajectory based on the subject’s weight and height, and this trajectory also achieved a similar lift as the trajectory designed by relying on the opinion of the subject. This method can be used for the design of the reference trajectory in the compliant control of the piggyback robot, which realizes the comfortable lifting of the care-receiver.

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.

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.

Motion Analysis and Tactile-Based Impedance Control of the Chest Holder of a Piggyback Patient Transfer Robot

Patient transfer, such as carrying a bedridden patient from a bed to a pedestal pan or a wheelchair and back, is one of the most physically challenging tasks in nursing care facilities. To reduce the intensity of physical labor on nurses or caregivers, a piggyback transfer robot has been developed by imitating the motion when a person holds another person on his/her back. As the chest holder supports most of the weight of the care-receiver during transfer, a human-robot dynamic model was built to analyze the influences of the motion of the chest holder on comfort. Simulations and experiments were conducted, and the results demonstrated that the rotational motion of the chest holder is the key factor affecting comfort. A tactile-based impedance control law was developed to adjust the rotational motion. Subjective evaluations of ten healthy subjects showed that adjusting the rotational motion of the chest holder is a useful way to achieve a comfortable transfer.

TECHNOLOGY TRANSFER ASSISTANCE PROJECT BRINGS VA HEALTH CARE IDEAS TO LIFE

Clinicians and staff of the Department of Veterans Affairs Health Care System (VA), who provide services to veterans, have invented many devices and methods for improving veterans' lives. However, translating those inventions to the market has been a challenge due to limited collaboration between the clinical inventors and the scientists, researchers, and engineers who can produce the prototypes necessary for licensing the technology. The VA Technology Transfer Program office and the Human Engineering Research Laboratories, a research laboratory with experience with developing prototypes and licensing technology, jointly developed a program called the Technology Transfer Assistance Project (TTAP) to bridge the gap between clinical inventors and prototypes ready for licensing. This paper describes TTAP and provides examples of the first inventions that were developed or enhanced through TTAP.

A consumer assessment of women who use wheelchairs

LAY SUMMARY

Female Veterans and female athletes with disabilities express concerns with mobility devices that are male-centric and do not address their unique needs. It is important that the needs of women are given the same attention as those of men. The following study asked groups of women who use wheelchairs or scooters, including Veterans and athletes, about their experiences. Twenty-four women, recruited from two sporting events for Veterans with disabilities, were asked to fill out a survey and participate in a focus group where they would discuss their views on mobility aids and related services. There were four major themes women often mentioned when they talked about using their mobility aids: usability (how they like using it), service delivery (how they get help with it), well-being (how they feel), and design (how it looks and works). Participants were concerned about the ability to adjust their device to their needs, how people obtained a device, and how they felt about using the device. Female wheelchair and scooter users recommended several changes to mobility aids that would improve the devices and improve the lives of women who use them.

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.