Approximately 15.000.000 strokes occur worldwide each year. Roughly half of the patients suffer from Hemiplegia, a condition that inhibits you from using one side of your body due to damages in the brain.
Typically, one of the first things patients want to relearn is walking to regain mobility. In order to create new connections in the brain and hence relearn movements, the correct movement has to be performed repeatedly over a long period of time. Unfortunately, intensive rehab often stops too early which leads to long-term compensation strategies instead of proper recovery.
Nova, your new set of home therapy smart pants, allows you to efficiently continue your rehabilitation at home.
Integrated sensors at the bottom of the pants legs measure your movements. They can track how you move your legs in order to observe which movement you intend to do. Next, the PCB's algorithms will calculate how the movement needs be tweaked in order to perform it correctly. Contracting cables at the inside of your joints will then give you a hint on how to walk by slightly pulling your leg into the right direction. Anyhow, the cables do not move your leg all the way up – since it is a brain injury, we need to train the brain to do the movement. Therefore, it is only supposed to guide the user to perform the right movement by giving a hint at how to do it correctly.
Moreover, the sensors can measure your weight distribution. They will vibrate once you put your body weight on your strong side for too long to remind you of using your weak side more often.
Our integrated battery and efficient motor will get you through the whole day. You can simply charge the components overnight and plug them into a clean set of nova pants in the morning. The pants itself are washable and can be worn underneath normal pants.
Therapists recommend two minutes of exercises every hour to allow the brain to recover effectively. Exercising every hour can easily be forgotten. Hence, our additional app sends you reminders and guides you through small two-minute sessions. It tracks your movements and visualizes how it needs to be tweaked if necessary.
The app also provides you information about correctly performed steps and informs you about your latest accomplishments.
Based on the collected information, your therapists can adjust the exercises and give feedback on your rehabilitation from a distance at any time.
Through the combination of the guidance from the pants, the detailed feedback and reminders of the app and professional analysis and therapy adjustment of experts, Nova provides your brain enough stimulation for a successful recovery.
Nova is the result of a ten-week project at the Umeå Institute of Design, focusing on collaborative robotics. In a team of two, we explored the future of collaborative robotics in the rehabilitation area and ended up focusing on stroke recovery.
In order to get in-depth information about strokes, the secondary disease Hemiplegia, the patient's needs and biggest struggles as well as current rehabilitation therapies and products, we visited the Stroke rehab center at the Umeå hospital (Sweden), the neuro-rehabilitation center in Sävar (Sweden) and talked to a therapist from the "Dr. Becker Neurozentrum Niedersachsen" (Germany). Last-named is a clinic using the latest robots to enhance the effectiveness of current rehabilitation.
We found out that approximately half of the patients struggle from Hemiplegia. Hemiplegia creates a state similar to paralysis, but usually with a change of healing. Due to damages in the brain, patients can no longer control half of their body, even though the muscles are still intact. Which side is affected depends on where the stroke occurred in the brain.
The brain can often rewire itself after damages by creating new connections in healthy parts of the brain, an ability called Neuroplasticity. This way, movements can often be relearned. To activate Neuroplasticity, motions have to be performed repeatedly using the affected body parts.
There are robots on the marked that allow the patients to e.g. walk in a device that moves your legs manually. The therapists from the Umeå hospital criticized these a lot because hemiplegia was not a muscle injury, but a damage in the brain, so the most important part of the therapy was that the patient actively performs the movement in order to stimulate the brain. They described the current products as "big and bulky machines, focused on moving muscles instead of fixing the brain" and did not see value in them.
Talking to a therapist from "Dr. Becker Neurozentrum Niedersachsen" we found out complex, big robots often leave a scary impression on patients. Some would completely refuse to use them. In contrast to the therapists from the Umeå hospital, she valued these devices due to the amount of correctly performed repetitions that the patient can accomplish in a short amount of time.
All therapists we talked to agreed that nowadays, rehabilitation at home is much less efficient than in a rehabilitation center due to a lack of therapy access and being distracted by everyday life. Because of a lack of feedback at home, motivation easily decreases, and exercise sessions are often ignored.
Moreover, patients often do not feel in control of their rehabilitation. Treatments should be flexible and quickly adjust to their needs and capabilities. On the other hand, the therapists do not have any numbers or statistics to base their decisions upon but use what they see during the treatment as a foundation for decisions. Considering that therapists hardly see their patients during home-therapy, it is hard for them to tweak the treatment according to the patient's needs.
All therapists mentioned that even though it is important to train all body parts, learning to walk feels most important to most patients. Walking allows the patients to be more mobile and an independent part of today's society.
As a conclusion of our research, we focused on the question: "How might we enable stroke patients to regain a healthy gait through personalized treatment after being discharged from the hospital?" We decided to have a look at small-scale robotic components and focused on guidance and enabling repetition instead of moving muscles.
EXPLORATION & PROTOTYPING INTERACTIONS
We tested and explored lots of different sensors to measure movements and positions, such as DIY textile pressure sensors and triangulation systems. Eventually, we got directed to a sensor-combination used by professional runners to precisely measure their technique (and hence the foots position) through complex mathematical algorithms. If the position of a foot can be determined so precisely, it should not be any problem to measure if a leg is lifted correctly either. Using these sensors, we found a solution for the measuring, but not yet for the feedback.
We prototyped how people react to vibration on their legs and found out that everyone tried to move away from the vibration. Hence, we decided to use vibration to indicate weight shifting – if you need to put less pressure on one leg, the sensor unit vibrates, and people automatically shift their weight to the other side.
According to the therapists, the most important movement that needs to be trained is lifting the leg high enough. Patients tend to keep it in a stretched position and move it to the front in a circular movement on the side instead of lifting it up. Accordingly, indicating the "lifting" and how high to lift the leg was the most important way to guide a person. To create a precise indication of what to do, we integrated cables into the pants that contract at the inside of the two most important joints, the knee and the hip. Through a slight contraction, the patient gets the information to lift the leg. The pulling stops once the leg is lifted high enough. Due to gravity, we did not need an indication to move the leg down.
THE PRODUCT COMPONENTS
Nova consists of a pair of pants with integrated cables, two sensor units at the pants legs (one on each side) and a battery- and motor unit at the top back of the pants. Both the sensors and the battery- and motor unit can be removed in order to recharge them over night and to wash the pants.
The electronic components can be plugged into every Nova-pants, which means that you could have e.g. three pairs of pants but only one set of electronic components in order to have a clean pair of pants available at any time.
Since the pants itself are very thin (comparable with tight sport pants), they can be worn underneath normal trousers.
In order to guarantee that the cables are in the right position, the pants need to sit tight. Getting into tight pants can be a struggle for the patients, since one of their arms is usually also affected by hemiplegia. As a result, we integrated zippers that allow you to open them up whilst getting dressed. Due to the fabric in the back, the can not open up so much that you loose control. As a consequence, it is possible to close them with one hand only. Additional straps guarantee that they will not slide down.
The pants are supposed to be a device that patients use when they get discharged from the hospital and need further rehabilitation at home. A fully rehabilitation can take month or years – usually it isimpossible to complete the treatment in a clinic. Anyhow, we would like to introduce the product while the patient is still in the hospital to get him/her used to the product before he/she must deal with it alone.
THE NOVA APP
As an addition to our Nova Pants, the Nova App provides statistics, sends reminders, acknowledges the patient's accomplishments and guides him through his daily set of exercises.
There are two versions of the app: One for the patient and one for the therapist. The therapist can set up which and how many exercises the patient should do every day. They can simply choose those from an integrated pool of exercises. The patients will get reminders throughout the day to perform their exercises. The Nova App always suggests a task from the exercises chosen by the therapist that would fit best into the situation. If the patient has been sitting for multiple hours, a task where standing or a stretching movement is involved might be a better choice than an exercise where you are sitting down. The app also makes sure that you perform a variety of exercises to challenge you. During the exercise, the patient will get verbal guidance by the app ("Move your leg higher up!", "Well done, keep that posture!") and can visually see their movements vs. the intended movements.
Moreover, the patient's app counts your steps and shows you statistics about your daily activity if desired. The therapists can also see statistics about the patient's activity in their app. Furthermore, they can see which exercises have been done and when they were performed. According to the therapist from the Umeå hospital, this is very valuable information for them to know how the patients perform at home and consequently adjust the treatment.
The app also allows the involved parties to easily communicate and hence acts as a bridge between patients and health experts without requiring much time or high expenses.