Origami-Inspired Vibrotactile Actuator (OriVib): Design and Characterization

The use of vibrotactile feedback, in place of a full-fledged force feedback experience, has recently received increased attention in haptic communities due to their clear advantages in terms of cost, expressiveness, and wearability. However, designers and engineers are required to trade off a number of technical challenges when designing vibrotactile actuators, including expressiveness (a wide band of actuation frequency), flexibility, and the complexity of the manufacturing process. To address these challenges, we present the design and characterization of an origami-inspired flexible vibrotactile actuator, named OriVib, with a tunable resonance frequency (expressiveness), an origami-inspired design (flexible, soft contact with the human body), and a streamlined manufacturing process (low-cost). Based on its characterization, the fabricated OriVib actuator with 54 mm diameter can produce up to 1.2 g vibration intensity where the vibration intensity increases linearly from 6-11 V input. The resonance frequency is tunable through the characteristic diameter (the resonance frequency decreases in an almost inversely proportional fashion as the diameter increases). As for the thermal signature, the OriVib actuator maintains its temperature below 38 $^{o}C$ when actuated within 6-8 V. In terms of repeatability, the OriVib maintained an average vibration intensity of 0.849 g (standard deviation 0.035 g) for at least 2 million cycles. These results validate the effectiveness of the OriVib actuator to offer an expressive, low-cost, and flexible vibrotactile actuator.