Difference between revisions of "Flight Computer"

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m (Spiral Details: formatting)
(updated the software section to reflect the current status.)
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Spiral 1 - Design
 
Spiral 1 - Design
  
I have a borrowed Arduino Uno board and just ordered two pressure sensors (so I can break one by accident later).  The idea is to use a [http://en.wikipedia.org/wiki/Spiral_model spiral development model] to incrementally increase the features and capabilities of this flight computer.
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I have acquired an Arduino Uno board and just ordered two pressure sensors (so I can break one by accident later).  The idea is to use a [http://en.wikipedia.org/wiki/Spiral_model spiral development model] to incrementally increase the features and capabilities of this flight computer.
  
 
See the '''Future Design''' Section below for the breakdown of the spirals.
 
See the '''Future Design''' Section below for the breakdown of the spirals.
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==Hardware==
 
==Hardware==
 
* [http://arduino.cc/en/Main/ArduinoBoardUno Arduino Uno] - [http://www.atmel.com/dyn/resources/prod_documents/doc8161.pdf datasheet]
 
* [http://arduino.cc/en/Main/ArduinoBoardUno Arduino Uno] - [http://www.atmel.com/dyn/resources/prod_documents/doc8161.pdf datasheet]
* [http://www.sparkfun.com/products/8161 SCP1000 MEMs Pressure Sensor] - [http://www.sparkfun.com/datasheets/Components/SCP1000-D01.pdf datasheet]
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* [http://www.sparkfun.com/products/8161 SCP1000 MEMS Pressure Sensor] - [http://www.sparkfun.com/datasheets/Components/SCP1000-D01.pdf datasheet]
  
 
==Software==
 
==Software==
* Not yet done
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I finally found a [http://dl.dropbox.com/u/4961781/scp1000_operate_ver5.pde sample code] that does not give me garbage results. The pressure seems to be fairly realistic, although a bit on the low side. Right now I'm getting a pressure reading of 99kPa which is a little low. However my temperature is reading 40C at room temperature. Putting the sensor and Arduino into a freezer I saw the temperature drop by approximately 40C, as expected, so this might just be an offset issue. More testing is necessary to figure out the issue.
* Since the pressure sensor uses the SPI interface, I am using the [http://www.arduino.cc/playground/Code/Spi SPI library] for the Arduino
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=Future Design=
 
=Future Design=
 
==Components/Features==
 
==Components/Features==
* Atmospheric Modelling
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* Atmospheric Modeling
 
* Inertial Measurements
 
* Inertial Measurements
 
**  Accelerometer
 
**  Accelerometer

Revision as of 13:03, 22 October 2011

Creator:
Gtpyro
Status:
Research
Born On:
22:03, 18 November 2010 (CST)
Last Updated:
13:03, 22 October 2011 (CDT)

Overview

This is a flight computer meant to go into a rocket. It is based on an Arduino micro-controller and will eventually be quite fancy.

Current Status

Spiral 1 - Design

I have acquired an Arduino Uno board and just ordered two pressure sensors (so I can break one by accident later). The idea is to use a spiral development model to incrementally increase the features and capabilities of this flight computer.

See the Future Design Section below for the breakdown of the spirals.

Current Design

Hardware

Software

I finally found a sample code that does not give me garbage results. The pressure seems to be fairly realistic, although a bit on the low side. Right now I'm getting a pressure reading of 99kPa which is a little low. However my temperature is reading 40C at room temperature. Putting the sensor and Arduino into a freezer I saw the temperature drop by approximately 40C, as expected, so this might just be an offset issue. More testing is necessary to figure out the issue.

Future Design

Components/Features

  • Atmospheric Modeling
  • Inertial Measurements
    • Accelerometer
    • Roll Measurements
  • GPS
  • Parachute deployment
  • Telemetry
  • Control via Bluetooth/Wifi

Knowledge Points

  • Data Logging
  • Communication with a ground station (telemetry)
  • Communication with a cell phone controller
  • GPS
  • Flight state sensing
  • Control Algorithms
  • Simulation Platform

Spiral Details

  • Spiral 1:
    • Make atmospheric measurements by recording the static pressure and converting it to an associated altitude measurement
    • The SCP1000 Pressure sensor also measures temperature so this improves the accuracy of the measurement
  • Spiral 2:
    • Spirals 2a and 2b can be done concurrently and I have not prioritised these
    • Spiral 2a:
    • Spiral 2b:
      • Use the altitude measurement (and the IMU measurement) to trigger other events based on the different stages of flight
      • This includes deploying the drogue parachute at apogee and the main parachute at some present height above ground (typically 500 ft to 700 ft)
  • Spiral 3:
    • Add GPS measurements into the mix.
  • Spiral 4:
    • Telemetry. This will be the hardest step as I know the least about RF.
  • Spiral 5:
    • Remote status, arming, etc.
    • I want to implement this in Android such that the remote for this functionality is a cell-phone but the general idea is to make is as easy and portable as possible so several different platforms will be looked at (Blackberry, iOS, Palm). (Reminder to self: this is a good place to learn C++ and Android programming)
  • Spiral 6:
    • Multi-stage/Multi-controller operation (see this link for RF communication between Arduinos)
    • Things I haven't thought of yet.