Dave Walsha, sales manager at precision drive system supplier EMS, looks at how micromotors are advancing rehabilitation equipment.
According to the World Health Organisation (WHO), over two billion people are living with a health condition that benefits from rehabilitation. Innovations in rehabilitation engineering are giving patients with once debilitating health conditions independence and higher quality of life.
The process can include helping patients find ways to improve how they move around, such as through physiotherapy, altering their environment and supporting them with mobility aids.
Mobility aids such as wheelchairs, lifts and prosthetics provide patients with support and assistance that allows them to perform activities they would otherwise be unable to. For instance, a stair lift can enable a patient with arthritis to ascend and descend stairs, thus allowing them to live in a house with multiple floors.
To attain the force needed to physically support a patient, many mobility aids are driven by powerful, high precision micromotors, with powered prosthetics and exoskeletons at the forefront of rehabilitation engineering.
Precision prosthetics
The earliest practical prosthesis discovered is a wooden toe from Egypt, which is around 3,000 years old. Prosthetics have come a long way since then, now being made from advanced materials, such as carbon fibre, and some even being robotic. Thanks to advances in engineering, over 45,000 people in England are benefiting from lower limb prosthetics alone.
Prosthetics need several qualities to perform as closely as possible to natural limbs. If the prosthetic is robotic, it must be lightweight to reduce strain for the user and to provide greater comfort for the wearing body part.
It’s important that the powering motors are small to avoid making the prosthetic bulky, allowing it to perform agile movements and look closer to the typical human form. It also helps the prosthetic limb fit into smaller spaces, such as when reaching for an item in a full kitchen cupboard.
The motorised prosthetic must perform with precision and variable functionality. For example, the same limb must be able to forcefully pull open a door or hold an egg securely without cracking it. The motors must be highly accurate to ensure the prosthetic executes its actions correctly, such as pressing a lift button on target. It’s also important that the powering motors are quiet, so the prosthetic remains relatively inconspicuous, and the user isn’t constantly disturbed by unnecessary noise.
Exceptional exoskeletons
However, motorised wearable devices are not just for those who require a prosthetic limb. For patients who have lost mobility due to a spinal cord injury, rehabilitation exoskeletons can be a revolutionary part of their recovery process.
While wheelchairs provide patients with increased mobility, independence, and quality of life, they do have some drawbacks. For instance, patients who spend long periods in a wheelchair in the same position can develop other health conditions, such as osteoarthritis and pressure ulcers.
Because of these issues, physiotherapy is required to keep the body moving, but typically relies on the support of multiple healthcare professionals, crutches, and a treadmill, and is a difficult process for all involved. Rehabilitation exoskeletons offer an alternative to get the patient moving, and offer greater independence, mobility and quality of life benefits than using a wheelchair alone.
Many exoskeletons can be fitted and operated entirely by the patient. The patient’s body is strapped into the exoskeleton, which has a series of sensors and motors to coordinate movement, with a powering battery pack worn on the patient’s back. Some models also require the use of crutches, whereas others do not.
The motors are a crucial element of a rehabilitation exoskeleton, being responsible for driving the patient’s movements and supporting their gait. The motor systems must be precise to replicate human movement and offer the optimal amount of torque and motion control.
Fine speed control is vital in exoskeleton systems to ensure the user can perform a variety of movements, from walking at pace to carefully navigating a steep incline. Being able to work under load is also important for tasks such as descending a staircase or sitting down.
Advanced engineering
Design engineers must select high performance, reliable motors that meet the demands of rehabilitation equipment. EMS is the sole UK supplier of FAULHABER motors, which are all made in a precision manufacturing process. The FAULHABER BXT series, used for rehabilitation equipment, has a flat construction which helps keep prosthetics and exoskeletons streamlined in design.
Rehabilitation is a demanding process but offers significant benefits to the patient. Motorised devices, such as prosthetics and exoskeletons, are transforming patients’ lives by helping them regain mobility and independence beyond traditional rehabilitation methods.
