Speakers and Transducers - Haptic Devices for Augmentation, Entertainment, and Wellness
The music and the auditory world encompass not only airborne sound energy but also structure-borne energy, which is perceived by our haptic senses. The ability to interact with the world through vibration and touch is central to all of our lives, and now increasingly so. In experiencing live sound, our haptic perception contributes to the realism, and conversely haptics can strengthen the illusion and simulation of reality.
Sound is energy made by vibrations and at a concert you see the performers, hear the music, and feel the bass haptically through structure-borne and soft tissue sensations. While audio magazines focus on what we hear, and audio-video publications also detail what we see, haptic sensations are not a topic commonly “touched” by publications and yet they augment our senses.
In the January 2021 issue of, we provided a thorough exploration of bass shakers and haptic devices with a focus on music and home theater reproduction. We promised to return to the topic and further explore tactile technology and the wide range of unconventional haptic applications.
The ability to perceive and interact with the world through vibration and touch contributes to the realism, and conversely haptics strengthen the illusion and simulation of reality. The smoothing vibrations of haptic therapies have proven in many clinical studies to calm the nervous system and improve heart rate variability (HRV) as a safe, non-invasive stress relief tool without drugs or side effects. Clinical studies have shown positive interaction with depression, PTSD, bipolar, insomnia, and autistic users.
Reproduction of this tactile component can be achieved through the use of a transducer popularly known as a “bass shaker” coupled, sized, and tuned into the specific platform. These transducers pass low-frequency vibrations into them so that they can be felt.
Bass shakers have the power to intensify everything while improving the sensory interaction. For gaming, home theaters, movie theaters, discotheques, and theme park rides, this “tactile” component is able to add a fourth dimension to reproduce the tactile impact of explosions, engine sounds, thunder, and other bone-rattling low-frequency content.
First popularized by Pioneer more than 40 years ago with its Bodysonic bass shaker, used everywhere from discos to car seats, today’s haptics will give you a nudge when your smartphone is silenced, your Advanced Driver Assistance System (ADAS) will give you a poke when you are driving and feeling sleepy, or you might get a tactile “handshake” feedback from a touchscreen confirming your selection.
The functions and locations are truly all over the place with end users increasingly coming into contact with haptics in medical devices, smartphones/tablets, and other touchscreens for gaming, sport fitness, and more.
Haptic motors are what most of us initially encountered in flip phones using a micromotor with an off-center weight on the shaft. These encompass two common motor types: Eccentric Rotating Mass (ERM) vibration motors and Linear Resonant Actuators (LRA) vibration motors (also known as linear vibrators).
While the ERM haptic actuators are adequate to discreetly poke you in your pocket when getting a call during a meeting, these traditional haptic drivers only deliver simple vibration buzzes due to the narrow frequency range and non-agile response. For gaming and other audio applications, the latest efforts of these motor actuators are somewhat better, with effects ranging from subtle to sharp, and textured effects that simulate different surfaces and sensations.
The standardization of haptics for touchscreen user-interfaces is expanding in multiple consumer-facing products, from automobile dashboards, to smart appliances, and advanced game controllers, all incorporating “high-def” motor haptics.
Automotive applications for vibration transducers are omniscient. From haptic “shakers” built into driver’s seats to ADAS driving awareness alerts, the automotive applications for haptics and vibration transducers are a multi-part article in itself. The next generation of automotive system engineering for the car interior expands to solutions for individual seats, the driver’s touchscreen controls, which bump back (bilateral interaction) when you input is acknowledged so you do not need to visually confirm, and infotainment systems enhanced with sound and haptics in the headrest and the individual seats. There is no way to achieve this personalization and separation of programs and functions without most of the bass being transmitted haptically from the seats, all the while getting accident avoidance bleeps from the general direction of the threat — not to mention the vibration cancelation from the active engine mounts.
Discussing solutions from Skullcandy, Razer, AAC Technologies, SolidDrive, DropLabs, Flexound, Lofelt, Woojer, Fisher Wallace, Apollo Neuroscience, Dreampad and Resonate.