Real-time Sensorless Estimation of Position and Force for Solenoid Actuators

Abstract

In various fields, small actuation systems are required to aid human activities in a narrow space and to realize fine motions. Although some miniature actuators have been developed, the size of the sensors attached to them prevents the miniaturization of the systems. In this paper, a sensorless actuation system with a compact solenoid actuator is proposed. An input signal including the AC and DC components is used. The inductance and position are estimated from the AC component. The DC component is applied in order to drive the solenoid actuator. Simulations and experiments concerning frequency characteristics and simultaneous estimation are conducted to verify the validity of the proposal. From the results of the frequency characteristics, the position and force estimation are accurately achieved up to 10 Hz frequency. As a result of the simultaneous estimation, the position and force are simultaneously estimated in real time. This proposal is useful, because a small solenoid actuation system whose position and force are simultaneously estimated in real time without the need for any position and force sensors is realized.

Electromagnetic Linear Actuator providing High Force Density per Unit Area without Position Sensor as a Tactile Cell

“…where f denote the frequency (5) . Thus, if voltage and current amplitude of the actuator V amp and I amp can be masesured, the mover position can be estimated.…”

“…These are mainly concerning one-dimensional tactile actuation. Recently, device oriented researches for transmission of two-dimensional tactile sensation have been also conducted in various fields (5)- (11) . For transmission of tactile sensation, it is necessary to simultaneously transmit position and force information (1) .…”

“…The speed and volume of information in this field is low. Another application is concerning a two-dimensional tactile display, which needs fast and accurate control of the position and force (5) (6) (14) . Hereafter, this paper focuses on the actuator aiming at realization of a two-dimensional tactile display.…”

“…2 Actuator surface area (mm 2 ) responce speed input conditions in Fig. 2 Solenoid (5) 150.0 fast 0.1 A Piezo (7) 21. 3 very fast 150 V SMA film (8) 10.5 slow 0.6 A Pneumatic (9) 569.3 slow 100 kPa Magnetic micro (10) 4.0 fast 0.8 A Electromagnetic (11) 16.0 fast 0.2 A Fig.…”

Position and Torque Sensorless Motion Transmission Using Voltage Compensation

“…In addition to estimating position, sensorless estimation of force is also required for motion transmission. Although Nagai et al achieved simultaneous estimation of position and force using solenoid actuators (11) , it has not developed for general actuators such as DC motors. This paper shows position and force sensorless method for motion transmission using DC motors.…”