Home appliances and electronic devices are woven into the fabric of our daily lives and over time, we have become familiar with the switches, push buttons, knobs and keyboards that are used to control these devices. Slowly but steadily, a new class of control elements have emerged that now dominates the way we interact with almost every piece of technology. Known as Capacitive Touch technologies – these highly accurate touchscreens respond instantly using the electrical properties of the human body.
In order for a screen or any type of device to be considered capacitive, it must consist of several components. A capacitive screen is made of an insulating layer that can also be transparent, such as glass or plastic. If the insulating layer is transparent, then a thin trace of transparent conductive material is used to form electrical patterns on the inside of the insulating layer. The thin traces generate a magnetic field that is modified when a human touches the insulating layer. Essentially, when you stroke a capacitive touch screen with your finger, you cause a change in a specific region the magnetic field of the screen, which is measured by the circuit and used to trigger a function; for example on/off, volume control or light dimmer.
The benefits of incorporating Capacitive Touch into applications such as home appliances and automobile control panels are widely known. For example, touch control is more reliable than traditional buttons or knobs because it does not require mechanical motion and is less likely to wear out. The housing is also more robust and cost-effective which makes it ideally suited for rough or ruggedized environments, where dust and moisture can creep into the device. Also, using touch screen controls provides designers greater freedom for developing visually compelling products. Examples include industrial or home appliance applications, as well as next generation rollable and flexible ruggedized tablets for human-machine interfaces.
In high-tech factories, the process of integrating Capacitive Touch into next generation products is automated. High precision, six-axis industrial robots thoroughly scan a flexible circuit board and then scan the molded piece of plastic for specific features. The markings and fiducials provide precision motion and vision control for accurate component placement. The robots pick up the circuit board and place it on the plastic in one swift, exact movement. The conductive layers of a Capacitive Touch screen have just been assembled; and a task that even the most skilled operator could not perform is now completed in roughly two seconds.
Without manufacturing, specifically the benefits that are seen from automation, Capacitive Touch would still be in the lab and would not be part of our daily lives. Our interaction with smartphones, tablets and even automobiles compels our need for the proliferation of touch technology and the automation that enables it.
The addition of touch screens on household appliances and other home automation devices are being standardized. Connected appliances and home automation devices now have the ability to learn a lot about our home and our daily usage patterns. Home automation devices can take the burden off the user and increase efficiency by handling and automating tasks in the background.
Capacitive Touch not only enables automation within the home, the ubiquitous technology has made its way into the industrial environment to facilitate and create efficient industrial robots. Industrial robots have been around for over 60 years, but until recently, they were dangerous to operate around humans and very difficult to program. Now, industrial robots come with tablets that features Capacitive Touch. The tablet allows the arms to be easily programmed using an intuitive graphical interface. Innovations like these have reduced set-up time from several days to just a few short hours.
In just a few short years we have come from turning knobs to start the stove to touching glass similar to operating your smartphone. Where does human-machine interface go from here? Thinner glass? Different substrates, like rollable or flexible? Do we even need to touch the panel to activate a switch? How does automation enable these advancements?
Gesture recognition or proximity sensing is well within our reach and has many applications. This capability detects users from a fixed distance then wakes the system as the user approaches so that the system can be fully functional by the time the user is ready to press a button. A practical application: the washing machine is ‘asleep’ but ’wakens’ as the user walks into the room with a full basket of clothes. This is just one example of how proximity sensing could change how users might interact with devices by making them more intelligent, interactive and friendly.
Our growing global emphasis on energy-saving electronics will enable effective low-power strategies to minimize active time while maximizing sleep. With more and more devices beginning designed with power conservation in mind, this will be an important feature on all devices, not just portable ones.
No Apparent Technical or Market Hurdles
Should Moore’s Law (semiconductor technology performance doubles every 18-24 months) come into play, we could be in for quite a ride with Capacitive Touch. The automated processes that facilitate the creation and the technology of Capacitive Touch have only just begun to scratch the surface of its limitless possibilities.
What is the tipping point of automation? Will it be when industrial robots begin to build other robots? Or when will houses be automated from a single interface? Although they may seem far off, these scenarios may be just over the horizon with the technology and capabilities that are made possible through human-machine interfaces and Capacitive Touch.