After a much longer time than we have ever planned on June 2, we have finally published the full documentation of the Ventilaid device. All documentation, including electronic and mechanical elements and, above all, software, will be made available under an Open Source license on our account on the GitLab portal. We are therefore happy to announce the completion of this stage in Ventilaid’s development.
Because everyone has had to wait so long, especially you, as our supporters, deserve a few words of explanation. Unfortunately, research and development works are hard to assume strict deadlines.
Status and development of work on Ventilaid Mk3 open source device
At the end of spring 2020, we had an early BiPAP device prototype, which successfully passed all simulated use tests we were able to carry out (including tests on an artificial lung simulating, among others, ARDS). The design at that time was difficult to assemble. Individual copies of it differed in parameters depending on who was making the parts. The disclosure of such documentation posed a significant risk that the work done by other authors would be wasted. Originally, it seemed very close to enter into cooperation with companies experienced in the mass production of electromechanical devices, with them the prototype would be transformed into a design that can be implemented into production. As this perspective has still not materialized, we have focused our efforts on project preparation with a view to ‘production implementation’ by DIY enthusiasts and researchers.
Rather than precisely specifying size tolerances and seal types, we focused on creating a design that is immune to manufacturing errors and substituting similar components as available. The device produced in this way, for obvious reasons, cannot be legally certified. For example, each time a BLDC motor is replaced with a functionally identical motor, but with a slightly different shape, the model of the casing of the centrifugal blower must be modified accordingly, and the entire certification process must be repeated.
The resulting design is very easy to assemble compared to the June 2020 version, and moreover, many elements can be made using more than one technology. In addition, the modular design and preparation of part models allow for easy modifications for research purposes. Among the versions available in the repository, you can find, for example, experiments on the bladed diffuser and confusor, and the shape of the collector is described parametrically in a spreadsheet. The projection also includes an extensive set of vibration isolators, which allows to reduce the impact of any imperfections in the performance of the centrifugal blower rotor. Additionally, depending on the area of interest of the researcher duplicating our project, it is possible to run a diverse set of measurements, and therefore also control algorithms. The simplest system, with pressure measurement at the patient’s mouth and measurement of the turbine rotational speed. It is a minimal set that allows comfortable breathing in BiPAP mode at low pressures (up to about 12 cm). The system can be expanded to a total of 6 pressure and flow measurements. Among the models available in the repository, there are parts for measuring pressure and velocity at the inlet and outlet of the device, and on the possible oxygen line. A module for active regulation of oxygen flow is also under preparation. Over the past year, the stability of electronics has also been significantly improved. Thanks to the use of an extensive filtration system and motor voltage regulation, it was possible to expand the choice of power supplies for the device. By separating the motor control module into a separate two-layer board from the four-layer motherboard, it was possible to facilitate adaptation to the availability of integrated circuits. It should be emphasized that the current world situation has significantly disrupted the supply system, so such flexibility seems to be a necessity.
Plans for the future – research, education, new solutions
Although the device already fulfilled its basic functions a year ago, and today it is also very easy to produce at home, its significant development is still possible. Last year’s efforts focused primarily on the hardware layer. There is still a lot of room in the software for experiments on other control systems, on the expansion of the alarm system and on a cheaper user interface. Devices designed for research purposes, such as a proprietary artificial lung, are also waiting to be completed in publishing form. They can be used to verify other respiratory therapy solutions, which seems important in the light of press reports about the emergence of respirators that do not meet the declared parameters.
We have also started preparations for the publication of the developed solutions in the peer-reviewed scientific press. In addition, as far as possible, we want to create a set of educational materials on the details of the VentilAid project, aimed at broadening the group of people capable of solving similar technical problems on their own. This may prove particularly important if the ongoing disturbance in the supply chain of electronic components deepens.
Currently, we do not have the means to implement our own production of a certified device, therefore, we invite institutions interested in adapting the project to their production capabilities and certifying it in local conditions to contact us. We will inform you about all the progress, as before, by e-mail and through our social media channels.
Ventilaid’s assumptions have not changed, although circumstances are different.
We will continue to build open source solutions, which we hope will be useful not only in the context of the COVID-19 pandemic, but also in other emergencies.
Thank you once again for your help, trust, but also patience, because we are aware that we put her to a great test. Now, being able to calmly focus on matters not related to formalities and construction, we will make up for all the shortcomings that have arisen in connection with the project last year.
