The MC33794-based E-Field Serial Touch Pad is designed around the MC68HC908JK3 microcontroller. The touch pad connects through a PC’s serial port using the same protocol used by serial mice. Commands are performed by moving your fingertip around the system’s pads, which are aluminum. Clicking is performed by gently tapping the middle pad.
E-Field Serial Touch Pad - [Link]
This project combines a football ball and some electronics to measure the forces applied. The ball is equipped with a xmega board, 9 axis sensor board (XYZ accelerometer, XYZ gyroscope and XYZ compass) and a blue-tooth module. Ball also has 32 LEDs that are visible when thrown. [via]
Measuring football inertia – [Link]
This project is a resistance touch button based on simple components.
R1 is a simple protective resistor. On pins E1 and E2, the two electrodes are connected to perform the touch plates. T1 is a transistor amplifier. I choose to use a darlington pair transistor, because i want to have enough current amplification to drive loads such as a relay, even if your skin is completely dry. You could use a simple transistor as well if you plan to drive simple LEDs or other low current loads. The next transistor is a power switching transistor, able to deliver enough current for the relay. A capacitor is connected to its base, to eliminate bounces or other parasitic noise. It causes a slight ON-OFF delay, but it is extremely fast to notice.
Resistance Touch Button – [Link]
This circuit is a Dark Detector using a 555 timer IC. The 555 is configured as an astable oscillator to drive the piezo buzzer. Check circuit diagram on the link below.
“Dark Detector” using a 555 timer IC – [Link]
Parallax has introduced their Optical Finger Navigation (OFN) sensor module. This HID is designed to sense the presence of a finger and track its movement much like a mouse. Interfacing is via I2C, supply voltage between 3.3 and 5.5 volts, and convenient 0.1″ pin spacing for breadboarding. The datasheet explains the theory of operation as using an onboard Image Acquisition System that obtains microscopic images of the finger surface, and those images are processed by a Digital Signal Processor. [via]
Parallax Optical Finger Navigation module – [Link]
This project demonstrates how pyroelectric IR sensor can be applied in the detection of moving object. Passive IR detector does not emits any IR light by itself. It is triggered by the variation of IR light that comes from warm & moving objects such as human body. Dogs, cats & other household pets have smaller bodies & do not radiate sufficiently strong IR to trigger the detector. Therefore it is pretty well immune to false alarm caused by pets.
PIR Motion Detector - [Link]
This project shows how to build a sensor to trigger a camera’s flash using a microphone or laser pointer. The brain of the project is an Arduino and it will activate the flash at accurate timing to capture precise moments. You can easily add new sensors, or even run multiple sensors at once. Since the triggering of the flash is done in software it’s easy to add delays, or make a more complicated triggering algorithm based on multiple sensors.
Triggering a Camera’s Flash with Sound and Light – [Link]
Here’s a demo of the MMA7455L 3-axis accelerometer in SPI mode using the Bus Pirate. The MMA7455L has:
- 2/4/8g selectable measurement range
- 10bit or 8bit output
- force and pulse detection with interrupt
- I2C and SPI interface
Get the MMA7455L breakout board for $15 at Seeed Studio
MMA7455L 3-axis accelerometer - [Link]