Modeling and control of surface acoustic wave motors

This thesis introduces Rayleigh waves and describes the generation of Rayleigh waves. Furthermore, the principle of operation of a SAW motor is analyzed. The analysis is based on a contact model, which describes the behavior between slider and stator. Due to the contact model, the microscopic and the macroscopic behavior can be studied simul- taneously. This model explains typical SAW motor features and determines the influence of parameters. The influence of the model parameters on the SAW motor behavior is studied in order to find the requirements for an optimal contact between slider and sta- tor. The models are validated. To control the SAW motor a linear time invariant system model of the SAW motor is derived and the disturbance sources of the SAW motor are determined and discussed. For closed-loop control, it is useful to eliminate the exist- ing varying dead-band between input and slider velocity. To this end, different actuation methods are investigated. Furthermore, controllers are designed, implemented and tested. Finally, the motor design is studied to obtain an indication for the applied materials, the geometry, the construction, the actuation and the practical limitations. Moreover, a design trajectory, to find initial design parameters, is proposed

Parameter Variation of a Surface Acoustic Wave Motor

This paper investigates the influence of parameter variation on the behavior of a Surface Acoustic Wave (SAW) motor. To this end, a model of the motor is used to vary the parameters independently. This model indicates that an increase of the friction coefficient, the Young modulus and the radius of the spheres at the bottom of the slider gives a raise in both the velocity and traction force

Data analysis and modelling

This deliverable on data analysis provides guidance and general principles for: - pre-testing to check the usability of the system and the feasibility of the evaluation process, - controlling the consistency of the chain and the precision with different sampling schemes, - modelling the impact for each indicators and for an integrated evaluation including a systemic and multidisciplinary interpretation of the effects, - integrating and controlling the quality of space-time data from various sources (numerical, video, questionnaires), - selecting the appropriate statistical techniques for data processing, PI estimation and hypothesis testing in accordance to the list of indicators and experimental design, - scaling up from experimental data and identified models to population and network level. Experimentalists stress the role and importance of a preliminary field test in FOT. Three main objectives have been defined to make a preliminary diagnosis of usability of the systems and to check the relevance and feasibility of the evaluation process. These preliminary tests are very important for the practical deployment of the FOT as well as for the overall scientific evaluation process