Because of the nonlinearity of the elastic sensitive element and the signal noise ratio,the precision of the traditional force sensor can hardly be higher than 0.02%.A force sensor with electromagnetic force balance lever structure was introduced.The sensor utilized a controllable electromagnet which can generate the controllable electromagnetic force to offset the load while the value of the load can be obtained by the coil voltage,which solved the problem of signal noise ratio.By analyzing the electromagnetic force curves under different temperature by the method of piecewise linearization，the electromagnetic force with high linearity was acquired,which solved the problem of nonlinearity.Test results indicated that the linearity of the sensor was 0.001%,and its precision was 0.003%.
