Kemet Introduces a Piezoelectric Film Haptic Actuator for User Interfaces

With the FFAA Haptic Actuator from Kemet, a division of the Yageo Group, it is now possible for electronic devices to interface with users via their sense of touch.

 

The FFAA Haptic Actuator from Kemet. Image courtesy of Yageo

 

 

What is Haptic Technology?

The word “haptic” refers to our sense of touch. Haptic technology involves enabling an electronic device to stimulate the human sense of touch through allowing us to feel motion, vibration or movement. A simple example would be an on/off button that imparts a vibration to the human finger that successfully turns it on and off.

 

What are Piezoelectric Haptic Actuators?

The piezoelectric effect occurs when pressure is applied to crystals such as quartz, resulting in the generation of electricity. It works in the other way, too – on the application of electricity, the crystal itself changes shape. Piezoelectric haptic actuators take advantage of the latter effect. Electrical impulses from the controlling electronic device cause the haptic actuator to change shape, perhaps hundred of times per second, and this vibration is felt by the human operator.

 

Kemet’s FFAA

Kemet describes its new device as a piezoelectric polymer film haptic actuator. It is designed to be embedded directly into an OEM product’s exposed surface. When touched by an operator, the unit acts as a “haptic skin”. At the appropriate time, the units will impart sensations that can, for example, impart tactile sensations that will make an altered or virtual reality experience seem that much more vivid and real.

The image below is a simplified illustration of the workings of the FFAA.

 

Image courtesy of the FFAA datasheet

 

The microcontroller generates the series of impulses that compose the vibration. And the amplifier beefs up the signal to the point that it is of sufficient magnitude for the actuator. The human touching the actuator feels the vibration, pulse, series of clicks or whatever tactile measure has been specified by the microcontroller and passed onto the actuator.

Kemet call attention to two devices from Microchip that can be used to drive the FFAA haptic actuator, the HV56020 and the HV56022.

 

Specifications for the FFAA Film Flex Assembled Actuator

• Size: 14.1 x 18.5 mm
• Weight: 56 milligrams
• Thickness: 0.6 mm
• Out of plane displacement: ≈200 µm
• Operating voltage: 212 Vpp @150 Hz
• Operating frequency range: 10 to 500 Hz

The device is specified as being installable on flat, curved or flexible surfaces. In this article, the company presents a guideline as to how to exploit the FFAA into a variety of mechanical situations

 

Applications

Kemet envisions two broad use cases for its new device

 

Products with hand contact:

• Virtual Reality (VR)
• Augmented Reality (AR) 
• Gaming controllers, including gloves
• Remote control
• User interface capacitive touch surface
• Computer Mouse
• Track pad

 

Products with lips contact:

• Medical equipment
• Musical instrument (mouth piece)

 

Physical Information

• The FFAA operates over a temperature range of +15 to +60℃

 

Environmental Concerns

• Adheres to RoHS
• Reach compliant