Springtines

Springtines are a class of miniature resonance devices consisting of elastic prongs, or tines, anchored at one end to a substrate via a compliant spring element. The term combines spring and tine, and in MEMS and related fields they are designed to vibrate when actuated, producing acoustic output or acting as frequency-selective sensing elements.

Construction and operation: Each springtine comprises a tine made from metal or polymer, mounted at its base to a micro-spring, either a cantilever or serpentine structure. Actuation methods include electrostatic, piezoelectric, magnetic, or thermal stimuli. The resonant frequency depends on the tine length, thickness, material, and the preload in the spring. They can be implemented as single units or arranged in arrays to provide multiple resonant modes or tunable filtering.

Applications: They are used in compact acoustic devices, tactile feedback systems, MEMS sensors, and tunable filters in RF and musical prototyping. Arrays of springtines can generate a spectrum of notes or serve as multi-element resonator banks, while individual units function as precision timing references or vibration sensors. Their ability to operate at small scales with modest actuation energy makes them suitable for integrated micro-systems.

Development and context: Springtines emerged in MEMS research as a means to combine small size with adjustable resonance. They face challenges such as mechanical wear, damping, and fabrication complexity, but offer advantages in compactness and low power. Ongoing work explores materials, packaging, and integration with readout electronics.