Neosim, a company based in the Swiss city of Chur, is highly knowledgeable in the lung physiology of intensive care patients. Used in the teaching and training of medical professionals, especially respiratory therapists and intensive care physicians, Neosim lung simulators allow realistic resuscitation practice on dummies. By contrast with lung simulators already available, the ones supplied by Neosim operate completely autonomously. They provide support for a wide variety of respiratory treatment techniques and automatically display results in real time.
The client
Neosim, a company based in the Swiss city of Chur, is highly knowledgeable in the lung physiology of intensive care patients. Used in the teaching and training of medical professionals, especially respiratory therapists and intensive care physicians, Neosim lung simulators allow realistic resuscitation practice on dummies. By contrast with lung simulators already available, the ones supplied by Neosim operate completely autonomously. They provide support for a wide variety of respiratory treatment techniques and automatically display results in real time.
The task
Risk-free training for emergencies
The 2,500 gram LuSi training dummy was developed by Neosim in collaboration with Solve especially for the purpose of training doctors in the assessment of lung function and the risk-free application of respiratory therapy for babies. One of the main advantages of this new development is the fact that LuSi can be used regardless of location.
The solution
Real-life mapping of lung function.
The challenge for the Solve project team consisted of developing the electronics, including their software, for a baby lung simulator. The brief was to mechatronically replicate the lung function and communicate the acquired data wirelessly in real time. The lung simulator also needs to be able to be used independently of location, which is why it also has to be possible to power the dummy with rechargeable batteries. In addition to developing the electronics, the task was to provide the customer with a firmware framework that allowed him/her to monitor and/or control the sensors and actuators using simple interfaces and to transmit data via Bluetooth. With the help of the framework, the customer was able to implement the application firmware (lung physiology) him/herself.
Wide-ranging knowledge is called for
The high functional diversity of the electronics to be developed required expertise in various technologies. This included, for example, the microcontroller programming of systems operating in real time and linking to the computer via a Bluetooth interface, as well as the implementation of an MP3 codec and a file system that will allow the playback of sounds in the future. A low-power circuit ensures reliable supply by means of a rechargeable battery.
The compact all-rounder
All functions required for lung simulation and communication with the PC are integrated on the electronic board that was newly developed for LuSi. A Cortex M4 microcontroller is responsible for control and communication. On this, the real-time operating system has been programmed. A bellows-like device is responsible for the chest movement and simulation of the lung function. This is operated by a DC servo motor. The power electronics for controlling and setting the speed of the motor are included on the electronics board. The valves for the air supply are also controlled by the software. A Bluetooth module for communication with the PC is also installed on the PCB, as well as a charging circuit and monitoring for the NiMH batteries. In addition, the connected sensors record measured values such as pressure, air supply, CO2 production and volume. The microcontroller communicates with the higher-level PC via Bluetooth. The data communication transmits the measured values as well as the parameter settings, such as lung mechanics, breathing control and some special effects. This communication was realised by using SPP (Serial Port Profile). The development of the drivers and frameworks required at the computer end were also part of the specification for the job.
The order included the design of the schematic, the layout and the EMC-compliant design. Finally, the system was rigorously tested and subjected to extensive trials.
Scoring high marks for expert knowledge
As a typical ambitious start-up, Neosim possessed a minimal budget and limited experience in both low-level development (RTOS, framework and drivers) and firmware development. In working with Solve, Neosim found the ideal combination of both disciplines. Solve already had the requisite expertise in electromechanical lung simulators and therefore could consult the customer on possible cost-saving potentials. This resulted in a technically perfect and cost-optimised solution for LuSi.
"The competences of Solve and Neosim were perfectly combined by Solve project manager Fabian Schnellmann, resulting in maximum benefit for Neosim. The result was excellent; cost and time budget were met.
Thanks for being such great people to work with!
Josef X. Brunner, CEO neosim
