Mouser - White Papers

Mouser Electronics White Paper Main Types of Haptic Devices A diverse range of haptic technologies use mechanical, electromechanical, or magnetic stimuli to impart sensations to users. Vibrotactile, electrotactile, and force feedback devices are more common, while ultrasonic, pneumatic, or hydraulic devices are used for specific applications. Vibrotactile Feedback The most common type of tactile feedback is vibrotactile feedback, such as vibrational feedback from smartphones, wearables, and other interfaces. These devices use vibration-inducing components to convey information to a user. Components for this type of feedback include vibration motors used in gaming controllers and sonic haptic transducers used in entertainment immersion enhancement systems. Electrotactile Feedback Electrotactile devices use electrical stimuli to induce nervous system effects on the body, replicating the nerve sensations that a user would feel if physically interacting with an object or environment. Ultrasonic Air-based ultrasonic haptics devices use ultrasonic generators to impart physical sensations to users. Also known as ultrasonic tactile feedback devices, these systems provide a touchless haptic experience by generating noticeable pressure regions to a user's skin. Examples include arrays of ultrasonic generators with advanced control algorithms that allow for multi-point ultrasonic feedback and a wide range of intensities. Force Feedback Force feedback kinesthetic devices—mechanical or electromechanical—simulate motion and resistance to motion. For instance, some gaming steering wheels use force feedback electromechanical motor systems to emulate the resistance an actual driver would feel while operating a race vehicle. Another example is using springs or pulleys to simulate the forces needed to manipulate virtual objects. Pneumatic & Hydraulic Possibly the oldest types of haptic feedback, pneumatics use air pressure actuators and hydraulics use non-compressible fluid actuators to replicate interactions with virtual objects. Piezoelectric Technology for Haptics Piezoelectric technology plays a pivotal role in modern haptic systems, offering precise and energy-efficient solutions for delivering tactile feedback in various applications. Fundamentals of the Piezoelectric Effect Piezoelectric materials generate electric charge (i.e., an electric field) when exposed to mechanical stresses and vice versa with the inverse piezoelectric effect. When mechanical stress is applied to a piezoelectric material, the reorientation of the electric dipoles within the crystal lattice causes the spontaneous separation of charges from within a crystalline structure and generates a measurable surface charge. The presence of a static electric charge generates an external electric field (Figure 4). Meanwhile, the inverse piezoelectric effect functions in reverse, where an external electric field causes stress within a piezoelectric material. Figure 4: Applying mechanical stress to a piezoelectric material reorients electric dipoles within the crystal lattice, causing charge separation and generating a measurable surface charge. (Source: Mouser Electronics)

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