Device to facilitate motion
MOVEMENT is vital to our body, just as food, water and oxygen. A lack of motion expedites the body’s degeneration (both nerve and muscle). However, there are diseases and injuries that have shown to inflict debilitating damage on the human body and significantly change and even limit the body’s ability to move.
“If you lose your ability to walk because of a stroke, surgery or an injury, you would need to undergo physiotherapy. During the initial stages of physiotherapy, the therapist’s main target is to guide your legs through the basic motions for walking. The more advanced forms of physiotherapy technology are generally more expensive,” says Dr Alpha Agape Gopalai, course coordinator (Mechatronics Engineering) at Monash University Malaysia’s School of Engineering.
Artificial stimulation of muscles is one such technique, where short current pulses are sent to a specific muscle group. During this therapy, the targeted muscle group contracts and relaxes according to the predetermined artificial stimulation pattern. However, one of the weaknesses of the artificial stimulation technique revolves around the muscle activation strategy. This is unlike the natural recruitment strategy, which only activates the necessary class of muscle fibres in relation to the perceived required force.
“If you look at the natural recruitment process, there is a gradient. For example, if you are picking up a tomato, you perceive how much force to exert so that you do not squash it, whereas, in the artificial recruitment process, you would lose your fine motor skills, and in this case, you might squash the tomato,” explains Dr Alpha.
It is with this in mind that Dr Alpha, with Saeed Pirbodaghi, PHD student at Monash University Malaysia, invented a device that would measure the force needed to deliver adequate stimulation for patients to move
Developed at Monash University Malaysia, Ambulate Me comes with sensors at its joints that, when combined with functional electrical stimulation (FES), delivers calculated stimulation signals to the muscles. This combination is what allows users to experience the load-bearing mechanism of their bodies, which goes a long way in their rehabilitation journey.
their limbs. The device is currently focused on the motions of the lower limb.
It is an exoskeleton that the group refers to as Ambulate Me which is meant to support the body by sending stimulation signals to the affected muscle group so the limbs can complete a particular motion. In the event where the recruitment only generates a weak contraction and is unable to complete the motion because of weakened muscles, the exoskeleton is meant to detect this and kick in to complete the intended movement.
Ambulate Me
Developed at Monash University Malaysia, Ambulate Me comes with sensors at its joints that, when combined with functional electrical stimulation (FES), delivers calculated stimulation signals to the muscles. This combination is what allows users to experience the load-bearing mechanism of their bodies, which goes a long way in their rehabilitation journey. Dr Alpha and Saeed describe Ambulate Me as a product that complements FES treatment.
“When we combine these two systems, we don’t need to activate the entire muscle. We send pulses with high enough intensity to get you moving again. When you move and exercise, your muscles are synthesising new proteins and myofibrils, which leads to the building of muscle mass. We provide an initial stimulation to initiate patient motion so that patients can feel what it is like to support and balance their bodies when they start walking,” says Saeed.
Ambulate Me gives an initial trigger for the limbs to move (as much as the current state of the muscle allows). The embedded sensors then measure how much force has been generated and calculates the remaining trajectory and torque required to complete the motion.