EMBRACE
Independent Study under Dr. Mark Yim & Professor Nick McGill 02 2019 - 05 2019
Overview
The melancholy feeling of long distance separation limiting real-time interaction has attempted to be resolved via virtual belonging digitally. Inspired by the Beatles’ hit song I Want to Hold Your Hand, Embrace seeks to physically unify individuals who are not coexisting in the same space. An inflatable ellipse applies pressure on the palm and back of hand to simulate holding someone’s hand. Beyond the emotional aspect, Embrace attempts to relieve stress in a similar manner. Although monitoring user’s stress levels while wearing Embrace was not in the scope of this project, I do hope to continue refining the wearable to achieve a low-profile stress-reducing IoT product.
final design
Given that this was an engineering project, I focused mainly on the physical design of the wearable to achieve specific metrics as well as integrated with electronics.
Metrics -
pressure applied on hand (refined empirically) - 30mmHg = 0.58psi
Total area of pressure contact ~ 2in^2
Time to inflate to 0.58psi (refined empirically) = 6.2 seconds
Static Analysis & ergonomic study
electronics
The 12V micro pump is powered by a simple circuit featuring a DRV8833 motor driver, and logic controlled via Particle Argon to connect to the internet over WiFi. A locker switch allows for easy power on/off controls and is powered by a 3.7V, 1000mAh liPo. I initially prototyped the functionality of the pump and wearable by connecting the driver directly to the rails.
code
A added feature of Embrace is its ability to be connected to other’s lives. A text message from a loved one triggers the actuation of the pump, inflating Embrace to simulate that person holding your hand. This feature was prototyped and is still currently being refined to accept online functions.
Final Prototype
I modeled the final form in rhinoceros to be printed in TPE-like resin. The balloon was threaded through with music wire and secured with super glue.
process
I first began by gauging the range of pressures appropriate to most closely mimic the pressure of a human hand using a bike pump and later with a blood pressure cuff. After conducting several user tests, the ideal pressure was found to be ~ 0.58psi
I mocked up physical prototypes first with the idea of applying pressure to the entire hand. Using a latex glove, I needed a stiff material to prevent the glove from inflating away from the hand. MDF was the original solution, but the final prototype was made with a semi-flexible 3D printed SLA resin, and a latex balloon as the inflatable material for its elastic and airtight properties.
Take a look at my many iterations below, made of everything from compression gloves, to Ziploc bags, to balloons and pvc tubes.
