Project Inspiration is an initiative of TU Delft to donate ventilators to lower-income countries. The ventilator is designed such that countries can decide themselves whether to order or to (partially) replicate the machine. Their goal is to help countries with their shortage of breathing equipment and to provide basic healthcare worldwide.
Gerwin Smit is an Assistant Professor at Delft University of Technology and a specialist in limb prostheses and medical aids. He initiated Project Inspiration with colleagues and also students to address the expected shortage of ventilators as the crisis unfolded. The pandemic situation meant a number of extra challenges for these medical engineers. For example, a shortage of supplies caused by the shutdown of the Chinese supply chain. Besides that, medical devices are subjected to a battery of tests before they can be placed on the market. It goes without saying that this takes time, and in this situation time was of the essence. Gerwin couldn’t help asking himself how they could make many mechanical ventilators, certified and proven to operate safely, in a very short amount of time?
He asked the museum authorities if he could borrow the ventilator, and whether he could take it apart…
He figured that the concept should be based on an existing device. Additionally, the concept should contain simple parts that would be easy and quick to manufacture. Gerwin looked at the history of respiratory devices and found the East Radcliffe Ventilator, a model commonly used in Europe from the ‘60s to the ‘80s. The National Museum of Boerhaave in Leiden in the Netherlands is a museum with a large collection of medical devices. They had one of example this specific model.
To analyse this machine, the project group needed to take a close look at it. Gerwin made a bold decision and called the museum. He asked the museum if he could borrow the machine, and importantly, whether he could take it apart. At first, this bold question surprised the museum. Usually the staff wear white gloves to even touch the machines. After some deliberation the museum agreed, because of the unusual circumstances and the noble cause. Gerwin and his colleagues collected and carefully transported the ventilator to their workplace, where they dismantled it over a weekend. They analysed the concept and the basic principles and came up with the first prototype just one week later.
The original machine contained a Parvalux motor, with a bicycle hub and bicycle gear for speed control. The company has over 70 years’ experience in designing and manufacturing fractional horsepower geared motor solutions. The team reached out to Lee Weston from Parvalux to help with selecting the right motor, and Parvalux responded by swiftly sending some samples. The team chose the Parvalux PM11-S motor, a permanent magnet brushed DC motor. It is spring-loaded for quiet operation and has a high starting torque of up to three times full load. It features an adjustable brush rocker for excellent commutation and maximum brush life. This is rather important, considering people’s lives will depend on it.
Prime Minister of the Netherlands Mark Rutte visits Project Inspiration and views the ventilators.
The initial idea was to create a mechanical analog machine, except the motor which was to be the only electrical part. An analog pressure gauge and a spirometer measured pressure and tidal volume. Since the original model the team concluded it would be a good idea to add a warning if the values were off. They therefore sought advice on the electronics to use from Interay Solutions b.v.
For their final prototype they chose electronic speed control from maxon. They chose ESCON 50/5, a small-sized, powerful 4-quadrant PWM servo controller because this provided fully stepless speed for their ventilator.
After finishing the final prototype, they needed help to scale up production. They therefore got in touch with their partner company Apparatenfabriek ARA b.v. The sister company to Interay Solutions b.v., ARA produces mechatronic systems for original equipment manufacturers in Aalten in the Netherlands. They were enthusiastic about producing the device themselves and offered their support. Public and private funding enabled the project to proceed.
Sharing their knowledge to help save peoples’ lives
Since then, Project Inspiration’s first ventilators have been donated and delivered to Guatemala, Panama, and Tanzania. The whole device is modular, and each country can decide whether they want to order ventilators or produce the device themselves. To share their gained knowledge with the world, all of Project Inspiration’s blueprints are available open source on their website. The devices were built locally in Guatemala and only the alarm and monitoring system were provided from the Netherlands. This included he Parvalux motor and maxon controller. With proof that the concept works, Guatemala is planning on making up to 300 ventilators thanks to Project Inspiration.
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