Acceleration Logger of High Speed Rocket

Overview

The ATtiny13 microcontroller is used to build the rocket accelerometer logger which is small enough to fit into the nose-cone of the rocket.

Explanation

Using a 3-axis, freescale mma7260 accelerometer, this logger is able to collect and record data. After the required data has been collected by the microcontroller, the 24C256 with 32k of EEPROM is used to store the data. This will provide enough space for measuring the flight of the rocket with sufficient resolution to view when graphed.

A 1K resistor is used to connect the outputs of the acceleration sensor to the A/D inputs of the AVR. The high-frequency crap of the internal oscillations going on in the sensor is filtered out by a low-pass filter with a capacitor. This method was replaced with a software where each pin is measured a few hundred times and averaging the measurements will have the same effect since the software routine is lighter than any capacitors. The software written in assembly will emulate an auto-loading UART.

The circuit is supplied by a 3.6V Li-Ion battery through an ON/OFF switch. The transient voltage is suppressed using a small decoupling capacitor in the power line.