Active Metal Touch Switches

Active Metal patented touch-sensitive technology brings a whole new level of durability to switches, sensors and control systems. Whether you define durability as long life, resistance to temperature and environment, resistance to physical damage or just a robust design, our technology excels at each of these criteria. Active Metal switches with no moving parts and virtually unlimited life span. With Active Metal imagine a seamless control panels where water or chemical intrusion is impossible. Active Metal switches made from 3/8-inch-thick stainless steel impervious to even a hammer blow. Active Metal sensors integrated with intelligence to report diagnostic information of sensor health or adapt to the surrounding environment to ensure uninterrupted operation. All these are possible and more. Existing touch sensitive technologies are fragile, limiting the scope of their uses and applications. With Active Metal, you can have the advantage of touch sensitive technology without sacrificing durability.

Ideal Applications

  • Decorative Lighting & Controls
  • Elevators
  • Faucet / Shower / Spa Controls
  • Food Processing
  • Gaming
  • Hazardous Environments
  • Medical Equipment & facilities
  • Military / Aerospace
  • Overlay and LED options are possible
  • Petroleum Exploration & Refining
  • Pharmaceutical
  • Recreational Marine
  • Security or Prison
  • Sterile Environments
  • Underwater Environments
  • Vandal Resistant Point of Sale

How Active Metal Touch Switches Work

The basic principle is the use of a material capable of supporting shear and torsional waves at ultrasonic frequencies. These waves can then be trapped or localized by contouring the material in the area to be made touch sensitive. These trapped energy regions are set into motion with ceramic transducers and act as ahigh Q resonator. These resonators ring like a bell and when a user touches the sensor surface the length of time the resonator ring is reduced. This reduction of the ring time is easily detected using a low-cost microcontroller circuit.

These contoured areas which resonate are referred to as resonant cavities. The contouring needed to define a resonant cavity can be done on the inside or the outside. Contouring the outside into a spherical shape or other shapes which form a natural touch target for the user’s finger.

In operation a threshold is chosen for the sensor design and operating environment. When the ring time is reduced to a value lower than a predetermined threshold, the microcontroller is programmed to indicate switch actuation. This is a continuous process occurring every few milliseconds.

Resonant cavities can be as small as 0.120” to over 1.00” in diameter The can be formed in round, oval, square or rectangular shapes, whatever is best suited to the design. Resonant cavities can be created in the material using traditional machining, chemical machining, the application of thin metal decals, even specially formulated epoxies can be used. The outward location of the touch position can be identified by popular paints, inks, anodizing, plating, laser etching and shallow engraving. Braille legends can also be used.


1400 Chisholm Trail Rd.
Suite F
Round Rock, Texas 78681