3D Printing and Maker Hardware Drive This Microfluidic Robotic Sleeve for Lymphedema Treatment
Costing far less than current solutions, this robotic sleeve is a great example of prototyping via COTS hardware and 3D printing.
Scientists at the University of Waterloo, in partnership with Myant Inc., have developed an inexpensive robotic sleeve designed to treat lymphedema through precisely-controlled compression via a microfluidic chip.
A common side-effect of breast cancer surgery, lymphedema causes fluid and proteins to build up in the tissues of the arm. Pneumatic or hydraulic compression sleeves are a common treatment, squeezing and releasing the arm to restore normal flow — but the devices are both expensive and cumbersome, leaving considerable room for improvement in the state-of-the-art.
"My definition of wearable is you can wear it and do whatever you want, and not be plugged into a wall," explains Carolyn Ren, co-author of the paper detailing a much lower-cost and more portable version of a robotic compression sleeve. "Bringing in the microfluidics field, we wanted to make the system battery-powered but without compromising the performance."
The microfluidic chip, built using a 3D-printed mold, has 16 individual channels, designed to offer varying resistance to create a timing delay as each chamber of the sleeve is inflated — inflating the ones lower down the arm first, in order to push fluid up and out of the arm. A traditional compression sleeve, the researchers claim, would require eight expensive valves to achieve the same — and cost thousands of dollars, where the team's prototype costs an order of magnitude less.
There are other advantages to the team's work beyond a dramatic reduction in cost, too. The sleeve is powered by a single 3.7V lithium-ion battery, making it portable, and its control system weighs less than an iPhone.
The team has proven the approach in concept using a 3D-printed forearm model and off-the-shelf hardware: 16 Adafruit pressure sensors connected to an Arduino Uno microcontroller, while the prototype control box uses an Adafruit air pump, SparkFun motor driver, two-way solenoid valves, and an Arduino Nano Every. Results proved promising, but human trials have not yet taken place.
The team's work has been published under open-access terms in the journal Biomicrofluidics, under open-access terms; patient recruitment is underway for human testing, with a view to patenting the technology and bringing it to market as a commercial product.