Abstract:As an important functional material, magnetic fluid has been widely used in the sensor field. An innovative magnetic fluid micropressure difference sensor is designed based on Hall elements in this study. Magnetic fluid is absorbed at the end of the cylindrical permanent magnet placedin the middle of transparentglass tube. In thisway, circular rings are formed,whichcanbeused to lubricate, sealandmake thefrictionhappenbetweensolidandliquid.Theringpermanentmagnet fixed onthe bottomofthe transparentglasstube isutilized to provide restoring force. When the permanent moves in the tube, the magnetic field of the Hall elements that acts as a transformation component will change with the displacements. Then, the voltage signals of the system are output. Finally, the optimized sensor has a diameter of 10 mm and a length of 80 mm. When it is combined with a 3 mm magnetic ring and a 50 mm permanent magnet, the measurement accuracy is 1 Pa within the measurement range of 0~1 000 Pa. The linearity error is 58%, the hysteresis error is 53%, and the repeatability error is 29%. The sensor is small in size and low in cost, which shows a strong practical value.