Star Micronics Automotive Division approached Blue Sparq, Inc. to produce a capacitive touch / haptics demo for Ford. The main goal was to produce a capacitive touch center console with haptic and audio feedback.
Haptic feedback, often referred to as simply "haptics", is the use of the sense of touch in a user interface design to provide information to an end user. We started by using a standard Ford Mustang Center Console control panel. We removed the heating and air-conditioning controls as well as the remaining mechanical buttons. We reproduced capacitive touch versions of the mechanical switches and mounted them into the existing molded frame
The AC Control Panel has touch buttons and sliders to control the temperature, mode and fan speed.
3 Forms of feedback were used to give the user confirmation that a button was touched: Indicator LEDs, Audio Feedback, as well as Haptic Feedback. Our special back uniform LED back lighting was used along with indicator LEDs to reproduce all of the features found in the original automotive buttons
In the video you can see that we mapped different button presses to different sounds. We can easily load different .wav files into our IC and play them when a button is pressed. A similar method is used for the haptic feedback. A haptic feedback transducer is treated like a speaker and a special audio file is played. Different audio files are used to create different sensations when buttons are touched.
After completing this prototype it became obvious that haptic feedback is a very expensive approach to feedback. Mechanically speaking, it is important that the surface being vibrated is suspended from the rest of the control panel. This can be achieved by using a foam rubber gasket. This is necessary for a good strong feedback.
If you constrain the panel, you will dampen the vibration, ultimately reducing the feedback.
We saw that the molded frame had a curved surface so we decided to also use our digitally printed conductive film technique. We were able to add 4 buttons to the curved surface which demonstrated our ability in adding capacitive touch to any form factor.
In summary, this project allowed us to concentrate on 3 different types of feedback methods:
Using our uniform back lighting to illuminate the button icons and graphics allowed us to reproduce all of the standard features of the control panel while adding capacitive touch.