1. Acquiring Data from an ADXL335 Accelerometer
living with the lab
Acquiring Data from an ADXL335 Accelerometer
DIGIKEY DKSB1002A Evaluation Board
3-axis accelerometer
Arduino Uno
microcontroller board

2. DKSB1002A Evaluation Board and ADXL335 Accelerometer
living with the lab
DKSB1002A Evaluation Board and ADXL335 Accelerometer
DKSB1002A is a prototyping board purchased for $20 from Digikey
Screw holes for mounting board onto “object of interest”
Board is ~ 20mm square
ADXL335 3-axis accelerometer chip
3-axis
±3g
this small chip is the ADXL335 accelerometer (this is an older model they are even smaller now)
COM - ground
VSS - power (we will provide 5V)
X acceleration in x-direction
Y - acceleration in y-direction
Z acceleration in z-direction z x y
the DKSB1002A is a board used to evaluate the accelerometer; if you were putting an accelerometer in a device like a cell phone, you would only use the ADXL335 chip (and maybe some capacitors)

3. Implementing a 3-axis Accelerometer: Wiring to Arduino
living with the lab
Implementing a 3-axis Accelerometer: Wiring to Arduino
COM - ground
VSS - power (we will provide 5V)
X acceleration in x-direction
Y acceleration in y-direction
Z acceleration in z-direction

4. Programming living with the lab associates a time with
void setup() {
Serial.begin(9600); }
void loop()
int xaccel = analogRead(0);
int yaccel = analogRead(1);
int zaccel = analogRead(2);
unsigned long timevar = millis();
Serial.print(timevar);
Serial.print(" "); Serial.print(xaccel);
Serial.print(" ");
Serial.print(yaccel);
Serial.println(zaccel);
associates a time with
each set of accelerations

5. living with the lab
Calibration x y z

6. Angle Measurement z x y θx = asin(ax/g) living with the lab +x qx ax
1g (perceived vertical acceleration) ax qx +x
θx = asin(ax/g)
Angle Measurement x y z

7. living with the lab
Example Application
The piezospeaker below outputs a frequency that varies with the acceleration in the x-direction. The equation for computing the frequency is chosen so that the device makes an audible noise that varies when rotating or shaking the device.
void setup(){Serial.begin(9600); }
void loop() {
int xaccel = analogRead(0);
int freq = 1500+xaccel*2;
tone(7,freq);
Serial.print(xaccel);
Serial.print(" ");
Serial.println(freq); }