Trellis is the product I made with my 2.009 group in the fall of 2015. Product Engineering Processes, a.k.a. 2.009, is MIT’s famed product development course in which students devise and build a product that addresses a real-life problem or need. We built Trellis, an actuated I.V. pole designed to help patients who need intravenous medication. The self-actuated pole follows the patient so that he or she doesn’t have to push it. This intense project took our group of 22 students four months to produce an alpha prototype. Watch the recorded product launch to see our presentation of Trellis (starting around 54 min in) in Kresge theater.
I worked on creating the patient-following software and also on some of the mechanical design. In order for the pole to detect the patient, we created a tether that clips to the patient’s clothing. We thought this would be the least intrusive way since the patient already needs to be connected to the pole through the I.V. line. The tether stretch and angle are detected by potentiometers to measure the distance and angle of the patient. Trellis attempts to follow the patient’s trajectory while maintaining a constant distance. We wanted Trellis to be smart when following the patient, so instead of always driving towards the patient (this would cause it to crash into wall corners) we programmed it to remember the patient trajectory and only turn where the patient turned. My biggest contributions were: 1) designing the mechanical device that incorporated the tether and potentiometers to sense the patient location, and 2) programming the patient-following behavior in ROS.
The tether is attached on the pole’s end to a string potentiometer to measure distance, and it goes through a regular potentiometer, inside the tether device (below), to measure angle. This design of tether allows for measuring about 220˚. I designed the tether device to be 3D printed.
Some of the earlier versions of Trellis that I worked on that lead to the final one:
Swivel: Designed for easiness to walk and steer and for the ability to stack multiple devices.
This next version of Trellis was intended to be easily maneuvered single-handed and also to have a small base. The small base would be achieved by storing most of the liquid at the bottom and having a non-intrusive pump refilling a small IV bag at the top for the medication to be delivered by gravity.
Amado Antonini 