Measurement
A dedicated mainboard PCB has been meticulously designed to encompass all the essential components necessary for load cell and pressure sensor measurements. Additionally, it facilitates precise control over the flow rate of the peristaltic pump and seamless data transmission to the UI software. By incorporating these vital functionalities into a single, intelligently designed mainboard PCB, the system achieves optimal efficiency and integration, ensuring accurate measurements and smooth communication between different components.
Design
The current iteration of the urodynamics system relies on the utilization of an Arduino Nano as the primary microcontroller. To cater to the specific power requirements of individual components, a series of buck converters are employed to convert the incoming AC electricity into various DC voltages. For precise measurements, a multiplexer is utilized to gather data from the bladder and abdominal pressure sensors. Load cell amplifiers and ADCs play a crucial role in acquiring accurate readings from the load cells. Additionally, a pulse width modulation circuit is implemented to effectively control the peristaltic pump’s speed. To ensure a streamlined and robust setup, all of these components are carefully soldered onto a main board and enclosed within a waterproof container. Furthermore, DIN connectors are employed to enable seamless input/output communication with the external subsystems.
Manufacturing
- Order a main board PCB from a discount PCB manufacturer (or print in-house)
- Solder all components to the PCB
- Connect each output to a female DIN connector
- Fit the main board within the waterproof container
- Fix the female DIN connectors to the outside of the water proof casing
Signal Processing
The microcontroller efficiently collects measurements from each load cell and pressure sensor in a sequential manner. These measurements are then transmitted to the UI software, enabling real-time monitoring and analysis. If the pump’s flow rate deviates from the desired range, the microcontroller promptly adjusts the pump’s speed to maintain optimal flow conditions. This proactive control mechanism ensures precise and consistent fluid flow during fluid infusion.
Component selection and manufacturing tips
- Solder the larger components first
- Create a connection between the the wire to the female DIN and the PCB. This allows the main board to be removed without having to sever the connection to the DIN
Urodynamics Without Borders 