A fully-open

Supply-chain resilient

pressure-control ventilator

for the people

The global COVID-19 pandemic has highlighted the need for a low-cost, rapidly-deployable ventilator, for the current as well as future respiratory virus outbreaks. While safe and robust ventilation technology exists in the commercial sector, the small number of capable suppliers cannot meet the severe demands for ventilators during a pandemic.

<Statement of cost> Moreover, the specialized and proprietary equipment developed by medical device manufacturers is expensive and inaccessible in low-resource areas. Compounding the issue during an emergency, manufacturing time…

The People’s Ventilator Project (PVP) is an open-source, low-cost pressure-control ventilator designed with minimal reliance on specialized medical parts to better adapt to supply chain shortages. The PVP largely follows established design conventions, most importantly active and computer-controlled inhalation, together with passive exhalation. It supports pressure-controlled ventilation, combined with standard-features like autonomous breath detection, and the suite of FDA required alarms.

<Statement of purpose>

Hardware

PVP is a pressure-controlled ventilator that uses a minimal set of inexpensive, off-the-self hardware components. An inexpensive proportional valve controls inspiratory flow, and a relay valve controls expiratory flow. A gauge pressure sensor monitors airway pressure, and an inexpensive D-lite spirometer used in conjunction with a differential pressure sensor monitors expiratory flow.

PVP’s components are coordinated by a Raspberry Pi 4 board, which runs the graphical user interface, administers the alarm system, monitors sensor values, and sends actuation commands to the valves. The core electrical system consists of two modular board ‘hats’, a sensor board and an actuator board, that stack onto the Raspberry Pi via 40-pin stackable headers. The modularity of this system enables individual boards to be revised or modified to substitute components in the case of part scarcity.

Links to system: … Mechanical overview … Electronics overview

Software

PVP’s software was developed to bring the philosophy of free and open-source software to medical devices. PVP is not only open from top to bottom, but we have developed it as a framework for an adaptable, general-purpose, communally-developed ventilator.

PVP’s ventilation control system is fast, robust, and written entirely in high-level Python (3.7) – without the development and inspection bottlenecks of split computer/microprocessor systems that require users to read and write low-level hardware firmware.

All of PVP’s components are modularly designed, allowing them to be reconfigured and expanded for new ventilation modes and hardware configurations.

We provide complete API-level documentation and an automated testing suite to give everyone the freedom to inspect, understand, and expand PVP’s software framework.

PVP Modules

GUI

A modular GUI with intuitive controls and a clear alarm system that can be configured to control any parameter or display values from any sensor.

Controller

... Manuel write this

IO

A hardware abstraction layer powered by pigpio that can read/write at [x Hz]

Alarm

Define complex and responsive alarm triggering criteria with human-readable Alarm Rules

Common

Modules that provide the API between the GUI and controller, user preferences, and other utilities