| abstract |
A pressure controller for a fluidic bladder has in sequence a pump, a first fluid line, a supply pressure sensor, a second fluid line, a bladder having an inlet coupled to the second fluid line, a bladder outlet coupled to a third fluid line of substantially equal length to the second fluid line, a return pressure sensor, and a fourth fluid line coupled to the return pressure sensor and returning fluid from the pump to the reservoir. A pressure estimate is formed by establishing the second fluid line length and inner diameter as the same as the third fluid line length and inner diameter, and forming the pressure estimate by averaging the supply pressure and return pressure. The pressure controller receives a setpoint pressure as a command and data over a wireless channel, and computes a head pressure offset by turning the pump off and measuring the supply and return pressures. |