Circuit Board for Bare-Bones Ventilator Moves Toward Production with Radio Amateurs’ Help

Radio amateurs continue to play key roles in developing the electronic control system for an open-source/architecture, modular, low-cost human patient ventilator. The device itself was designed by researcher Sem Lampotang and his team at University of Florida Health — the school’s academic health center — using such commonly available components as PVC pipe and lawn-sprinkler valves. The idea is to create a bare-bones ventilator that could serve in the event of a ventilator shortage.

“The way I looked at it is, if you’re going to run out of ventilators, then we’re not even trying to reproduce the sophisticated ventilators out there,” Lampotang said. “If we run out, you have to decide who gets one and who doesn’t. How do you decide that? The power of our approach is that every well-intentioned volunteer who has access to Home Depot, Ace, Lowe’s, or their equivalent worldwide can build one.”

His team is working on adding safety features to meet regulatory guidelines, then they will run engineering tests to determine safety, accuracy, and endurance of the machine, which can be built for as little as $125 to $250.

Dr. Gordon Gibby, KX4Z — a retired associate professor of anesthesiology at the University of Florida and an electrical engineer — is among those involved in the project, developing control-system prototypes. He reports that a trial printed circuit board is being created, populated, and tested prior to large-scale fabrication. “This should lead to a documented open-source design that can be replicated or improved upon by any interested manufacturer,” Gibby said, noting that the board could be built anywhere in the world, based on the Arduino Nano microcontroller.

“A huge amount of work has gone on in the design of the circuit boards,” Gibby told ARRL. “We have at least two, maybe three designs, ready for fabrication.” Current design specifications and a video of prototypes have been posted online. The Arduino-based control software will set the respiratory rate and other key parameters in treating critically ill coronavirus victims. Other radio amateurs involved in the control system aspect of the project include Jack Purdum, W8TEE, and uBITX transceiver maker Ashhar Farhan, VU2ESE.

Using a Groups.io forum, up to 140 volunteers have been studying or working to push the project to completion. Software is being created by multiple volunteers, with amateur radio operators involved in that phase as well.

The ventilator’s valves will precisely time the flow of compressed oxygen into a patient with lungs weakened by viral pneumonia in order to extend life and allow time for the body to clear the infection.

Among the project’s assumptions: The Food and Drug Administration will waive clearance for the bare-bones design, if a massive shortage develops; traditional medical components and supplies used in ventilators will be in short supply, and transportation will be impaired or disrupted

Source:ARRL