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MEMS (Micro-Electro-Mechanical Systems) Accelerometers are in widespread use as tilt-sensors in mobile phones and cameras. Simple accelerometers are available both as ic-chip's and cheap development pcb-boards.
Wireless chips are also affordable and available in assembled circuits, with matched antenna-network and decoupling-caps onboard.
Hook both wireless board and accelerometer up to a microcontroller via serial interface and you have a wireless controller with nintendo-wii functions.
Then build a receiver with the same type of wireless chip and pwm-controlled rgb-LEDs, voila, you have wireless, tilt-controlled coloured room lightning.
Keep the transmitter-board level with breadboard facing up and the LED is cool blue, only blue led is active. Then tilt the transmitter in one direction and you mix in red or green depending on which direction you tilt it. Tilt all the way to 90 degrees, and you go trough all mixes of red and blue or green and blue until only red or green is active at 90 degrees tilt. Tilt a little in both x and y direction and you get a mix of all the colours. At 45degrees in all directions the light is an equal mix of red, green and blue, in other words, white light.
The parts used are available from internet hobby-electronic stores. Should be identifiable from some of the pictures.
Wireless chips are also affordable and available in assembled circuits, with matched antenna-network and decoupling-caps onboard.
Hook both wireless board and accelerometer up to a microcontroller via serial interface and you have a wireless controller with nintendo-wii functions.
Then build a receiver with the same type of wireless chip and pwm-controlled rgb-LEDs, voila, you have wireless, tilt-controlled coloured room lightning.
Keep the transmitter-board level with breadboard facing up and the LED is cool blue, only blue led is active. Then tilt the transmitter in one direction and you mix in red or green depending on which direction you tilt it. Tilt all the way to 90 degrees, and you go trough all mixes of red and blue or green and blue until only red or green is active at 90 degrees tilt. Tilt a little in both x and y direction and you get a mix of all the colours. At 45degrees in all directions the light is an equal mix of red, green and blue, in other words, white light.
The parts used are available from internet hobby-electronic stores. Should be identifiable from some of the pictures.
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Signing UpStep 1Transmitter with accelerometer
The transmitter is based on the Atmel avr168 microcontroller. The convenient red board with the 168 is an arduino-board with voltage regulator and reset-circuit. The accelerometer is connected to the avr with bit-banged i2c bus, and the wireless board is connected with hardware SPI, (Serial Peripheral Interface).
The breadboard is completely wireless with the 4,8V batterypack strapped underneath.
The wireless board and the arduino wee accepts up to 9 V and have onboard linear voltage regulator, but the accelerometer needs 3,3V from the regulated rail on the wee.
The breadboard is completely wireless with the 4,8V batterypack strapped underneath.
The wireless board and the arduino wee accepts up to 9 V and have onboard linear voltage regulator, but the accelerometer needs 3,3V from the regulated rail on the wee.
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link:http://cgi.ebay.com/ADXL330-3-Axis-3g-iMEMS-Accelerometer-Modules-/130384232195?pt=LH_DefaultDomain_0&hash=item1e5b817f03
Thanks :)
I bought the rf-module from sparkfun.com;
Transceiver nRF24L01+ Module with RP-SMA
sku: WRL-00705
Thanks for your interest!
Troy
The accelerometer post-prosessing is a oneline lowpass-filter in c-code. Look up lowpass on wikipedia.
avg_value += (read_value - avg_value)/a
where a is the lowpass filter constant.
just search for "software i2c", it's an assembly-file named something like i2cmaster.S. If I have some time to spare one day, maybe I'll post a cleaner version of the code, but don't stay around and wait for it.
The white breadboard with accelerometer measures tilt and sends this over the wireless link. The receiver makes the tilt-information into LED-commands and talks to the LED controller in the shiftbright-module.
uc1=microcontroller avr168
uc2=microcontroller avr169 butterfly
wirelessTX = transmitter module
wirelessRX = receiver module
~ = wireless link--> = wired interface
accelerometer -->uc1-->wirelessTX
~ wirelessRX -->uc2--> LED