Auxobrace - proof of concept model and working prototype
Design process summary of Auxobrace
Design process summary of Auxobrace
Experts evaluation at NUH and user testing on patients that have been discharged.
Internal structure of Auxobrace, consisting of 3D printed auxetic structures and a bending actuator
Visualisation of compression and actuation of Auxobrace on the body based on volume of air evacuated
Proof of concept activation device - mock up, only for working prototype.
What it does
Current braces do not provide adequate forces needed for stability and can be uncomfortable for patients to wear. By utilising vacuum mechanisms, Auxobrace creates bending and shrinkage forces that produce the ideal pressure and comfort on the human body.
Open heart surgery has played a significant role in my life. I underwent the procedure in 1999 at birth, had another in 2021, and anticipate needing one more in the future. While recovering from my most recent surgery, I endured a challenging and painful period of approximately 3 to 4 months due to the slow fusion of the sternum bone. Simple movements and activities required assistance from caregivers, and the available solutions proved ineffective. This experience sparked my motivation as a designer to reimagine sternal and cardiac rehabilitation, aiming to benefit and provide relief to a larger population.
How it works
Auxobrace is a vest-like device designed for patients after being discharged from the hospital. It incorporates a mini vacuum pump to remove air from its internal structure, resulting in targeted pressure and force around the chest. The internal structure comprises of mini cubes with precise gaps between them that close as air is evacuated, causing the fabric to shrink and contract uniformly. The sternum support section features a finger joint-like design that bends inward when air is removed, providing optimal inward support and stability to the sternum bone, ensuring it will not move or slide during any activity. Two front touch buttons allow patients to control the vacuum and release functions depending on how much pressure is needed for a variety of activities.
Auxobrace was created by working closely with domain experts from the National University Hospital (NUH) from day 1. Building off from my own experience and the input they provided on proper sternal rehabilitation led me to do rapid prototyping on dynamic casts. The initial concept derived from the conventional vacuum-packed rice in supermarkets which inspired me to translate that idea and apply it on the human body. Having the ability to become soft or rigid on demand was the definition of a dynamic cast. Similar to those rice packets, I substituted it with polystyrene beads as they were lightweight. By placing the beads in an airtight bladder made from TPU fabric, I was able to achieve a rigid form when a vacuum is applied. Many prototypes were made, worn and tested by the domain experts and myself, but there was still a lack in control of where the pressure points are targeting. Looking into the control of soft robotics was the breakthrough, as it opened up new ways targeted pressure could be applied and controlled on the body. Each new iteration was brought back to the hospital for the Doctors, Nurses and Physiotherapist to try on for qualitative evaluation. I then did my own testing with force resistive sensors to ensure safety before letting recovered patients try it on.
How it is different
Conventional sternal braces are very bulky and cumbersome. The elastic materials used are also very restrictive, which makes the user feel a constant pressure around their chest. This constant contact with the body gives rise to 2 issues, one being that this constant light pressure does not promote proper breathing patterns in the long run, and the other being that in hot weather, patients would tend to sweat with the device worn. Sweat near such big and fresh wounds increases the risk of infection, which could be more harmful than the surgery itself. In the current braces, the application method is also executed by using the patient's own brute strength which some elderly might find challenging. Auxobrace solves these problems by remaining sleek due to the nature of its internal built, drapes over the body without the need for elastic materials to hug the torso, and uses the passive vacuum pump for a 'force' to be applied just with a push of a button.
As of today, Auxobrace has received a Patent under the Registry of Patents, Singapore (serial number : 10202301484P) (4D Printing With Metamaterial – TPU Auxetic Structures + Bending Actuators In Vacuum). With the support from NUS and NUH, further developments are currently ongoing, such as optimising the efficiency of the internal structures, material choices, component layout, and overall usability. More works are also in the rough stages of development with the technology developed. Things such as various forms of compressive brace for different rehabilitation needs to the range of fashion accessories will be explored in the future.
NUS-JTC Medal and Prize (Design) - Best design project addressing the theme of innovation in the design of industrial facilities and infrastructure