Rebuilding the "Plastic Dog"

The problem

The “plastic dog” was a system of steppers, tubes, reservoirs, and sensors that simulated a cardiovascular system, pumping water to model blood flow. A renowned biomedical institute used it for training and education, but its hardware dated to the late 1960s and it ran on an old C program.

What we built

We replaced the hardware with modern components, including stepper motors and controllers, custom signal conditioning for medical-grade pressure transducers, and a low-cost National Instruments data acquisition card.

The new LabVIEW application has calibration, real-time simulation, and troubleshooting interfaces. It calibrates itself at startup, and in simulation mode students watch venous and arterial pressures respond as conditions change.