In this STAR interview, we speak to Rai MacLean of the Faculty of Engineering Technology (ET). STAR is an acronym for (S)ituation, (T)asks, (A)ctions, (R)esults. We also have many “star” colleagues at UT with an interesting story to tell. Rai MacLean works on biomechanical engineering and develops interface robotic technologies with the neuromuscular system, ultimately for enhancing human movement. 
Situation
What is/was the situation (S) of your research/initiative?
The English proverb 'you never know what you’ve got till it’s gone', or 'je waardeert niet wat je hebt totdat je het verliest' in Dutch, is very often true when it comes to walking ability. Most of us don’t notice how ingrained walking is in society until we experience walking difficulties in ourselves or our loved ones. Walking ability is strongly linked to independence and quality of life. Injury, musculoskeletal/neurological disorders like Parkinson’s disease, and ageing are all factors that negatively affect a person's ability to walk without aid. Common walking aids like canes and walkers (looprekken in Dutch) help with mobility, but these solutions are not ideal. Interaction with the environment is challenging when your hand(s) are busy using the walking aid. Furthermore, many people are resistant to using a walking aid because they are concerned a walking aid will define them as “disabled” or “old” to both themselves and others. We need solutions to improve walking ability that people are amenable to and don’t restrict engagement.
Although humans have walked on two legs for as long as we have existed, we still do not entirely understand all the intricacies of how we walk. Walking is an incredibly complex task requiring the coordination of a multitude of muscles and the integration of external information. The mechanism or method by which we control our walking is the topic of many debates. It is a lot easier to improve or augment something when you understand how it works. It is therefore important that we continue to strive to improve our understanding of walking.
Tasks
What tasks (T) were or are you currently working on?
The goal of our team is to address walking difficulties through assistive and rehabilitative technologies. Our research centres around wearable robots, otherwise known as exoskeletons or exosuits. We use exoskeletons to further our understanding of healthy and impaired human motor control to gait and balance. Our team also investigates and develops exoskeleton technology to assist and/or rehabilitate gait for clinical populations.
Actions
What actions (A) are you working on and who are involved?
We are investigating 'gait entrainment' towards improving mobility in people with Parkinson’s disease. Gait entrainment is a technology that subtly encourages stride (or step) frequency to converge to a specific target frequency. In our research, an exoskeleton provides small entrainment stimuli to the ankle joint at the target frequency. We investigate how gait changes when it is entrained, and the underlying motor-control mechanisms that drive gait entrainment. To build foundational gait entrainment knowledge, we record experimental data in a gait analysis lab with able-bodied adults and older adults. We use 3D motion capture, ground contact force, and muscle activity measurements. Our findings on healthy human motor control and entrainment act as the springboard to dive into investigating motor control and entrainment in people with Parkinson’s disease. We also investigate the potential and efficacy of gait entrainment as an assistive walking aid and rehabilitation therapy for people with Parkinson’s disease. Neurologists, clinicians, and people with Parkinson’s disease are all involved in our research and development.
Results
What results (R) do you hope to achieve and how will society (or UT organization) perceive them?
For society, we hope to develop a technology that will improve walking ability, and thereby quality of life, for people with Parkinson’s disease. If successful, gait entrainment as an assistive or rehabilitative technology will prolong independence and community engagement.
For science, our results will contribute to an improved understanding of healthy and pathological motor control, providing direction for future therapies and technologies.
