What it does
Assistive device for upright locomotion and sit-to-stand transfer
No matter how much technology advances or how much telecommunication becomes integrated in our lives, still going out for a breath of fresh air is very important for our social wellbeing. “QOLO” is designed to provide such experiences for people deprived of them due to unfortunate incidents. Stand up from a chair, moving to another place, and then sit down again. Cooking in kitchen, or looking for a book in library. All are simple behaviors, but not possible for some people with disabilities. To retrieve one’s natural behavior as one used to do before getting lower limb disability, QOLO is designed to be there for assistance, and to make things possible again. We enjoy going out to see something nice, or eating delicious food on equal height with friends or family. QOLO helps people tied to a wheel chair elevate to the height or their mates again, to make something that used to be natural, natural again. I have always been fascinated by the concept of personal mobility, but rather than making something that healthy people can use I noticed that there are many people who cannot stand up and walk upright in the first place, so I decided to make a vehicle that assists standing up and upright locomotion for those who were deprived from this basic physical freedom due to unfortunate accidents.
How it works
This vehicle is designed to restore three of daily locomotion functions for persons with disability in lower limbs. The functions are stand up form a chair, locomotion with upright posture, and then sitting down on a chair. For this reason, the vehicle comprises two mechanisms, an assistive mechanism for sit-to-stand and stand-to-sit transfer, and a system for upright locomotion. Electric motors are heavy and expensive if the postural transition is to be assisted electrically. Furthermore, a user misses a chance to use own residual motor function if it is fully assisted. Therefore, we turned our attention to utilizing the upper body weight, since center of mass is lifted in an upright posture. Thanks to the upper body weight, center of the gravity is shifted when one bends forward or backward. Then we can control the transfer motion using this shift, and a user can control the transfer from sit to stand – and vice versa - by their upper body posture. With such a design based on human factors, the system does not require electric power for posture transfer, and the mechanism is constructed completely by passive mechanical parts. For control of upright locomotion, we also looked at upper body motion, which tends to lean towards the movement direction. In the design of the vehicle, we apply this concept into the locomotion control system as well, so the user can move forward simply by tilting their upper body forward, and turn any direction just by twisting the upper body towards that direction.
The design and development of QOLO went through several stages of conceptualizing, extensive design and review cycles, realization and testing. To conceptualize QOLO we have made many sketches of candidate structures and mechanisms for stand-up and upright locomotion support. Assist of stand-up function was particularly difficult to fix because we wanted to utilize the user’s residual motor function. Therefore, we decided to structure a passive mechanism, which assists a user’s motion and educes the residual functions at a same time. At this stage, we also ruled out all the design concepts that could have been obtrusive to the user’s upper limbs motion, to reach an unobtrusive design that does not hinder or obtrude the arms motion. Which came across in the inward design of the posture transfer mechanism that lays between the legs rather than on the sides. Such a vehicle is quite expensive and time costly to prototype. Therefore, we used a 3D CAD system and numerical calculations extensively to improve the structure and mechanical characteristics of the design. In fact, we spend more than three months designing, reviewing and modifying Qolo on the computer. To manufacture QOLO, we asked a metal-processing company to machine the parts in high precision. Then we assembled the vehicle with great care to mechanical rigidity and safety. Fabrication of the electric control circuit was also done in parallel with the mechanical fabrication. We designed control algorithms for the vehicle after all hardware was ready to move. After QOLO was ready, we tested the function and performance extensively with healthy people and a person with spinal cord injury who became a very valuable adviser for the project in a short time. We used advanced Motion Capture and Electromyography systems to test and evaluate the sit-to-stand motion, stand-to-sit motion and upright locomotion function. From those experiments we were able who confirm that sit-to-stand and stand-to-sit transfer in addition to upright locomotion were all functional and practical using the vehicle. We also received a lot of valuable feedback on the design and function of QOLO. Now, we are hard at work in designing the next generation of QOLO. We are paying great deal of attention to aspects of ergonomics and human factors. In the design of next generation, having in mind all the feedback and comments of people who tested the vehicle. We will not only seek mechanical improvements, but also look deeply into the exterior that ensures comfort and safety while using the vehicle.
How it is different
No entry into other competition.