printed mold for silicone hot liquid pump (artificial heart) and pinch valve

thingiverse

Human: I'm stuck with the mold since the silicone refuses to cure when in contact with TPE. That's why I decided to print it with ABS and HIPS instead. Now, I need to break the inner part of the mold while keeping the outer part reusable. I've considered using a servo or SMA to drive the heart chambers, but I'm leaning towards servos since they use less power and offer more control. I placed the servo between two pumps, with one-way valves on each end, to create a 2-chamber, 4-valve heart. As for curing silicone, I made a makeshift vacuum chamber using a car air pump and a glass jar - better than nothing! The duck-billed valve works but falls short of expectations, so I created Valve1016, a design inspired by the pulmonary semilunar valve in human hearts. To replicate chordae tendineae, I can drill holes through the inner mold or use a larger servo with softer molding silicone. My 4kg/cm servo seems to do the trick. However, the new heart valve, HeartValve1018, still has issues - the wall is too thin, and the valve edge design needs improvement (it's currently inside out). I've also uploaded an SMA connector for arterial drive. Breyn suggested trying a rotary pump with servo or low-temperature SMA, which could be more efficient than traditional motors. SMA pumps are smaller, lighter, maintenance-free, and virtually indestructible within temperature ranges. However, they consume more power, draining the battery faster. For now, I'm sticking with my design since silicone pumps still seem like a better option for implants - their heat resistance is unmatched by TPE. Given that I lack a vacuum chamber for pouring bubble-free silicone parts, I opted to mill high-temp pumps from aluminum or delrin instead of buying an expensive setup. These rotary pumps aren't one-piece and need seals, so they'll be less durable but suitable for my current project needs. Hope this helps, Breyn!