Fabrication of thermopneumatic PDMS membrane actuator for generating touch and application to braille code display device

Abstract

In information-oriented society and media age, communication and information exchange are occurred by using a myriad of media devices, vigorously. And the hardware side such as gaining experience and feeling at first hand having been strong formerly has been rapidly changed into the software side such as giving user the sense of the real through reproducing virtual environment using digital devices now. Therefore, research and development of haptic feedback device, one of the technologies for virtual reality, will be sure to be needed in the future and be one of important projects which should be progressed for improving our life style. Haptics is a relatively new field of study in the realm of sensory communications and has hit the mainstream. In 2000, there weren’t that many people who knew the word, “Haptic”. By 2004, any self-respecting gamer had it in a joystick at home, and cell phones buzzed. Haptic perception involves both tactile system through the skin and kinesthetic system of the position and movement of the joints and muscles, through the skin and the position of our fingers. In this thesis, I proposed, fabricated, and evaluated large deformable micro thermo-pneumatic polydimethylsiloxane (PDMS) membrane actuator in order to generate touch among tactile mechanism of human. The actuator is purposed to get over the limit range of the deflection, over 600 μm, even though device is made by micro electro-mechanical systems (MEMS) fabrication process and to generate enough activation force, over 3.6 mN to evoke touch sensation. After that, fabricated actuator is tried to apply to Braille code display device. Proposed actuator consists of four parts: a working fluid ($3M^{\trade}$ PF-5060), a PDMS chamber (7 mm × 7 mm × 0.55 mm) that acts as a reservoir for the working fluid, a PDMS membrane (3 mm × 3 mm), and a resistive micro-heater. The working process of the actuator is that as increasing temperature at the resistive heater, a phase of th...