After experiencing some issues with another project it was necessary to design and manufacture a simple, adjustable exhaust muffler. The project was design and CAM’ed in Fusion 360 and machined on my custom Warco CNC mill. This muffler was required to slow the rate of the exhaust on a soft robot project. The graph below shows the issue which I was experiencing during another project.
The “blue” line represents the position of the end-effector of the robotic arm. As the arm reaches the set point represented in “red” the control system (P controller) switches the solenoids and dumps the air from the soft module. But as you can see from the graph the rate at which the module is inflated does not match the rate at which it dumps the air, resulting in an unstable system. However, with this addition to the output of the dump solenoids, it was possible to push the system into stability.