Piezo-resistive force sensor with bumps on membrane structure

A braking system coupled to at least one wheel of a vehicle to control the braking force on the wheel, the braking system comprising:

• a pedal to apply initial braking pressure to the wheel;
• a braking device coupled to the wheel and configured to apply the initial braking pressure on the wheel;
• and
• a sensor to measure the braking pressure applied to the wheel, the sensor comprising:
• a plunger configured to receive the applied braking force, and having a ring-shaped first groove on a lower surface of the plunger;
• a disc-shaped membrane having an upper surface and lower surface, wherein the membrane is flexible according to the applied braking force received by the plunger, wherein an upper surface of the membrane has a ring-shaped first bump configured to complementarily fit the first groove, and wherein the lower surface of the membrane has a ring-shaped second bump;
• a sensing circuit centrally disposed on the membrane, wherein the sensing circuit measures the applied braking force when being bent or compressed caused by the membrane;
• a support plate having a ring-shaped second groove configured to complementarily fit the second bump, whereby the applied braking force received by the plunger is transmitted to the membrane, causing the membrane to flex, which in turn causes the bending or compressing of the sensing circuit, resulting in the measurement of the applied braking force;
• and
• a control unit electrically coupled to the braking device to control the braking pressure on the wheel, wherein the control unit is configured to receive the measurement of the applied braking force from the braking device, and to process the measurement of the applied braking force to control the braking pressure on the wheel.