P1: Nitrous at Balls in '08

GSE, Instrumentation and Test Equipment

Last Update, 8/21/07 by Stephen Daniel

Project Summary

This project includes all of the equipment needed to support a rocket both during test and at a launch.

At present we do not anticipate building a launch tower, but everything else is included.

Data Capture

Some testing serves to validate existing designs, some serves to provide new data as input to the simulator. In both cases we requireaccurate data to characterize the burn. Gathering quality test data is expensive. We minimize this cost in part by gathering only a few channels worth of data, and in part by building a data capture system that meets our needs but does not have lots of extra features and functon.

Goals:

  • Design and build a 4-channel data capture board.
  • Each channel takes a 0-5V analog input. (Load cells and other bridge sensors require external amplifiers.)
  • Record the data as 12-bits per sample, sampled at 4 KHz with good frequency response to 500 Hz.
  • Record data onto a FAT-formatted MMC (or SD) card.
  • Battery powered, intended to be placed on the stand
  • Able send real-time data to a PC for test an calibration.
  • General purpose enough so that some of the costs can be defrayed by selling some.

Documents

Hybrid GSE

The ground support equipment is used both for launches and for testing. It consists of two major components, the plumbing stack that delivers nitrous to the motor, and the control circuitry that manages all of the valves, the quick-disconnect, and the iginition.

Goals:

  • The GSE will be designed to promote and enhance the safety of the entire test and launch process.
  • Nitrous will be supplied by in commercially rented gas cylinders.
  • All valves will be rated for continuous duty. No over-voltaged solenoids.
  • All boxes, connectors, etc wll be high-quality long-life products. We intend the GSE to far outlive this specific project.
  • Subject to these goals, we will minimize cost.

Sub-projects:

Budget

  • High level budget was $600. We will be well over $1,000 by project end.

  • Spent $140 on break-out box PC fab
  • Spent about $260 on tank-top plumbing, including brass bits, a gauge, and 2 valves
  • Spent about $400 at Digikey on parts for the control boxes.
  • We still need to spend about $100 on front-panels.
  • We spent $50 on a dolly for the tank.
  • Spent ?? on test stand tower hardware