A test bench is designed to develop an inertial measurement unit. Micro electromechanical system (MEMS) type gyro and accelerometer sensors are placed on a rotating platform. Actual angular position is measured by an encoder. This paper presents design of various estimators to estimate the orientation of the test platform. Basically complementary and Kalman filter based estimators are designed and implemented on the test bench. Parameters of the estimators are optimized by using experimental data. Satisfactory results are achieved.