Issue 98, September 1998
Smart Rockets - Data Acquisition in Model Rocketry

SOFTWARE & SOURCES

SOFTWARE

Complete source code for this article is available via the Circuit Cellar Web site.

SOURCES

ADXL50
Analog Devices, Inc.
(617) 329-4700
Fax: (617) 326-8703
www.analog.com

Model rockets and rocket equipment
Estes Industries
1295 H St.
Penrose, CO 81240

MAX631
Maxim Integrated Products
(408) 737-7600
www.maxim-ic.com

PIC16C73
Microchip Technology, Inc.
(602) 786-7200
Fax: (602) 786-7277
www.microchip.com

Rocket-engine performance curves
National Assn. of Rocketry
P.O. Box 177
Altoona, WI 54720
www.nar.org

X25F128
Xicor, Inc.
(408) 432-8888
Fax: (408) 432-0640
www.xicor.com

Photo 1a—Here’s our smart rocket on the launch pad. Note the clear payload compartment containing the data-acquisition system and the copper contacts beneath the fins. The brown streak down the right side of the rocket is one of the two lines of conductive paint that bring the trigger signal to the payload. b—In this view of the data-acquisition system, you see the modifications made to the payload compartment. The brown patch on the rear bulkhead connector is conductive paint that forms a sliding electrical connection with the rocket body. To the left of the circuit board is a model-rocket engine.

Figure 3—In the ground equipment, the interface box connects the payload to a host computer for data transfer. Pressing the ignition switch on the launch control box (SW2) simultaneously ignites the rocket engine and triggers the payload to record data.

Photo 2a—The accelerometer is in the TO-100 can at the forward end of the board. Its axis of sensitivity is along the diameter of the can that crosses the tab. The connectors are for the trigger signal (yellow), serial communication (central three-pin connector), and power (green), which is shown connected to the lithium battery. b—The red and green status LEDs, the large black inductor, the mode jumper, and the reset button are visible on the wire side of the board.