This Small Business Innovation Research (SBIR) Phase I project, Robot-Assisted Patient Transfer and Rehabilitation Device, is to develop a device that provides institutional and home patients of limited mobility with a means to accomplish several important tasks for daily living. Several promising concepts that exploit robotics technology have been identified that may prove more effective than currently available transfer devices for both patients and caregivers. The proposers will conduct clinician-guided research & development activities to evaluate and further develop these robotic approaches to the bed transfer problem and arrive at a medically sound, operationally robust and cost-effective concept for incorporation into a multi-functional mobility device for institutional or home settings. The device concept(s) emerging from the effort will be evaluated by nursing professionals to determine the most useful and feasible combination of functions in a single apparatus.
The broader impact/commercial potential of this project will benefit civilian and military healthcare systems. In the civilian sector as well as the military, the aging of the baby-boom generation and the rising body mass of the average patient is contributing to increased demand for the proposed device. Furthermore, existing patient transfer methods result in more than 200,000 nurse and caregiver injuries costing approximately $1 billion per year in the US. The influx of injured veterans returning from the Middle East is a clear impetus to the development and introduction of new patient handling devices, as many of these veterans will be in need of mobility and/or nursing assistance for years to come. The proposed robot-assisted patient transfer and rehabilitation device can be used in hospitals, rehabilitation centers, physical therapy, nursing homes, and private home care. The device will significantly improve the patient quality of life while reducing nurse and caregiver injuries.
The primary objective of this Phase I project was to design and evaluate a concept for a device that would provide caregivers of patients with limited mobility an effective means of performing several common patient transfer maneuvers. In particular, the device would provide nurses and other caregivers with a single device that can perform both lifting and transporting the patient. The lifting functions would include lifting patients in and out of bed and on and off the toilet. A secondary objective was to design the device such that the patient alone can control the device to perform these functions. It will give disabled, infirm, and elderly patients who cannot manage the transition from bed to a chair a far greater degree of mobility and vertical lift capability than has been previously attainable. An experimental prototype of such a multi-functional device has been developed in the laboratory of the National Institute of Standards and Technology (NIST). This device is known as the Home Lift, Position, and Rehabilitation (HLPR) chair and has been designed to have many of the attributes that we have sought for this project. That device, however, presumes a degree of patient control and therefore does not satisfy our primary objective as a facilitator for caregivers. Another limitation is that the patient must possess considerable upper body strength in order to perform unassisted lifts. This limitation excludes a large class of patients that would otherwise be able to utilize some or all functions of the device. In addition to further evaluating the HLPR chair, we investigated existing solutions for patient transfer including overhead lifts, slings, and transformable gurneys in order to better understand issues and problems that existing commercially-available patient lift equipment does not address. We then conducted clinician-guided investigations to evaluate several robotic approaches to the bed transfer problem. The device concepts emerging from this effort were evaluated by nursing professionals at the University of Maryland School of Nursing (UMSON) to determine the most useful and feasible combination of functions in a single apparatus. We learned that an important function that would greatly aid many patient transfer device designs is the ability to insert a lifting surface under a patient on the bed without moving the patient. Currently the patient is "log-rolled" onto a transfer sheet or sling. A log-roll means the patient is rolled onto their side and a sling is placed on the bed where the patient’s back was prior to the roll. The patient is then rolled onto their other side and the sling is adjusted such that it will be flat and in the correct position when the patient returns to lying on their back. The lifting device concepts given in our proposal to NSF did not consider the log-roll problem. Once we learned that this is an important issue in patient transfer, significant effort was directed towards finding a feasible solution to this problem. We formulated a conceptual design of a robotic transfer device that inserts a lifting surface under a patient without need of the log-roll. We then assessed the device's feasibility, built a prototype, and evaluated the effectiveness of the prototype. In support of ATR’s effort, UMSON performed expert evaluation of the final robotic patient transfer design, and it was concluded that the device could help reduce the number of caregivers required for patient transfer and reduce injuries to both caregivers and patients. The robotic transfer device developed under this contract provides a promising solution that could improve the acceptance of patient transfer devices among caregivers.
