- 公益社団法人 計測自動制御学会
- 計測自動制御学会論文集 (ISSN:04534654)
- vol.50, no.7, pp.543-552, 2014 (Released:2014-08-02)
Our research group has worked on an ultrasound-based noncontact tactile display. It utilizes a nonlinear effect of ultrasound to produce a force in midair. It is known that an object in the ultrasound field suffers a force (acoustic radiation pressure) in the direction of the ultrasound propagation. The position of the force is controlled three-dimensionally based on the phased array focusing technique: A focal point of ultrasound is generated by setting the phases of hundreds of ultrasound transducers adequately. After the presentations and the demonstrations of this tactile display, it gradually came out that some researchers working on research fields other than tactile display liked to use this device for their own issues. But the previous prototype device had a bulky body and complicated wires, and so it took time and labor to carry, setup, and install it. These drawbacks limited the situations in which it could be used and prevented us from giving it a try to use it in other application areas. In order to break through this difficulty, we newly developed a compact device which generates a noncontact force up to 16mN. It was carried out by integrating driving circuits and cutting out the expandability of the device. This small-sized and light-weighted device is easy to use and so useful for exploring new application areas. In this paper, firstly, the principles of the device are explained. Secondly, the design concept and the specifications of the device are provided. Thirdly, the experiments show that the ultrasound is focused as the theory predicted, the intensity of the output force is surely controlled by PWM, and the frequency characteristics covers up to 1kHz. Finally, the collaborative researches based on the developed ultrasound device are reported as the evidence of application exploration.