Use of MEMS Inertial Sensors for Performance Improvement of Low-cost Motion Control Systems

The performance of a motion control system depends on hardware capabilities, such as sensor resolution and actuator technology. For a certain plant, an amelioration in performance can often be achieved by using better sensors. This however may require a redesign of the system, as the new sensor may not fit into the existing plant. As for the actuators, many motion control systems using stepper motors exist; these stepper motors known for their high torque ripple and limited dynamic performance, especially in the presence of mechanical resonances of the driven load. A possible solution is to replace the actuator with a better one; however, this again may require a costly redesign of the plant. To improve the performance of existing plants with minimal invasive modifications, our group has developed a set of solutions, based on the use of low-cost MEMS inertial sensors, which can be easily placed on the system to be controlled. We will show the manner in which we used such sensors to develop new control strategies, to enhance the performance of existing sensors and actuators, without major modifications to the plant. This will be demonstrated through some examples taken from both laboratory and industrial applications.