Capacitive (PCAP) Touch Sensor / Switch
Sometimes you just need to call something by what is does. The Really Useful Touch Switch is small (same dimensions as an SD card), programmable, adaptable - it is just simply, really useful!
There is also a fixed function (non-programmable) version.
These digital, projected-capacitive (PCAP) touch sensor switches detect object approach and object removal as well as human touch. Using the same sensing technology used in the touchscreens of smartphones, they will project touch and sense through almost any non-conductor, such as wood, glass, plastic, stone, ceramic, to a thickness of 3cm or more, while conductors can be turned into sensors.
The sensor output is a MOSFET transistor that may be configured to operate as a switch, PWM generator or TTL serial transmitter, allowing simple on/off signaling or switching of other devices, speed and intensity control, and advanced control of other electronic devices from media players to PC/Windows applications via binary data sequences and character strings.
A rule based system of events, conditions, actions and timers can be used to program both instant and delayed behaviour that may be different in response to either detect polarity and both start and end of detection.
Configuration information, including sensitivity and the operating behaviour, is stored in an onboard permanent memory and can be changed using Coastform's free QtBtn PC software, together with a simple USB / UART adapter, which also enables detect status and signal levels to be monitored in real time.
These devices are suitable for applications that are subject to environmental influences or even vandalism. They feature adaptive automatic self-calibration, drift compensation, and digital filtering algorithms that make the sensing function robust. They can permit the construction of 100% sealed, watertight sensors and control panels that are immune to humidity, temperature, chemicals, dirt accumulation, abrasion, and abuse.
The sensing area can be increased, if required, by bonding the touch switch to a conductor, such as a small sheet of tin foil, using double-sided adhesive tape.
The board is fitted with a small, cable-capturing, 3-pin socket for both power and signaling. The supply voltage, which should be DC in the range +5V to +24V, uses 2 of the pins while the 3rd is the switching and communications pin.
Interactive Architecture company Lotsmorehere found it really useful when they created an interactive window display for retailer SKK Lighting.
Here are more places it might be really useful
What is included ?
Interactive 3-D view
This interactive 3-D view of the touch switch takes a few seconds to load but allows viewing from any angle.
Videos
Specifications
Weight, touch switch only: 0.005Kg (5g)
Downloads
Controlling Windows Applications
Together with TouchPad.exe, the touch switches can be used to control applications in Windows.TouchPad - Windows app that enables touch buttons to control other Windows applications.
Programming
To program the Really Useful Touch Switch with different configurations and sensitivity settings etc, the following items are also needed:
Configuration files
Here are some example configuration files that can be programmed into the touch switch to define different behaviour: