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Table of Contents To Do and Status List 3rd Oct - 5th Nov 23 Sep - 3rd Oct Additional iTesa Requirements Architecture Scientific(-ish) stuff Git Nexus One Android NDK Tutorials Eclipse integration Accessing sensors in NDK STRaND related Other interesting stuff

To Do and Status List

3rd Oct - 5th Nov

1. How the app should be closed ?
2. Phone not responding ^new
3. Lock landscape/portrait mode
4. Statistical analysis (aj)^new
5. Binary Data Storage (aj)
   • Semi-complete; there are a good number of ways to do this however I am going for DataOutputStream DOS (as BufferedOutputStream is for Strings - I believe).
6. Also, using java.io.Serializable we can write the dataitem B.
   • learn this, and compare to straight DOS, then implement. (aj)
7. Conceptual Designs (aj)
8. understand android data formats
9. SQLite Database
   • Branch: jakub_preferences
   • OK. So far I found the bug that was causing the app to crash (bloody comma in SQL statement)
   • data saved : (timestamp, Bx, By, Bz)
   • database profiling (jc)
   • data saved: (timestamp, mag.|B|) GPS: (timestamp, GPS coords) Magnetometer (timestamp, |B|)
   • average data every N samples^new
   • measure sensor reading rate (FASTEST, NORMAL, GAME, etc.)^new
10. App options (accuracy, delay rate etc) (jc)
    • Branch: jakub_preferences
    • implemented basic menu with preferences (UI update refresh rate). It doesn’t work as expected yet because of the way the timer is set.
    • change the way UI is updated (run the sensor reading as service/add thread)
11. Plotting functionality - basic (jc)
    • Branch: (none)
    • write the code
    • add background picture^new
12. Merge the branches (jc)
13. Test the app, review the code (aj/jc)

23 Sep - 3rd Oct

1. setup repo on github (done)
2. write magnetometer test - check values (done)
3. freq of the measurement (do we actually have any numbers ? not that we need them but would be nice to have)

Additional

1. Get more tech details from STRaND (5th Nov)
   • data analysis, statistics?
   • SDK version ? interface to the external hardware ?
2. compare data storage latency
3. profile code!
4. calculate angle of sun based on time and GPS coords.
5. work out what are the things like sensorManager.MAGNETIC_FIELD_EARTH_MAX/MIN, RAW_DATA_X/Y/Z, and other * sensorManager features

iTesa

Requirements

(see checklist)

1. should be able to run for at least 90 mins w/o crashing or freezing
2. sensor measurements should be decoupled from the UI update
3. sensor measurements should be decoupled from the plot update
4. plot update should be decoupled from the UI update
5. option for selecting frequency of measurement/UI/plot updates
6. the code should be flexible enough to be able to choose between sqlite database and raw file for data storage

Architecture

(see checklist)

"There are two basic rules for writing efficient code:

Don't do work that you don't need to do.

Don't allocate memory if you can avoid it.

Scientific(-ish) stuff

• http://www.sensorplatforms.com/understanding-smart-phone-sensor-performance-magnetometer-2
• http://www.nasa.gov/centers/goddard/news/topstory/2004/0517magnet.html
• http://geomag.org/info/declination.html

- see the picture

• http://tes.jpl.nasa.gov/instrument/orbitcoverage/

Git

• http://cheat.errtheblog.com/s/git
• http://gitref.org/index.html
• http://progit.org/book/
• .gitignore when working with Android in Eclipse :

# built application files
*.apk
*.ap_

# files for the dex VM
*.dex

# Java class files
*.class

# generated files
bin/
gen/

# Local configuration file (sdk path, etc)
local.properties

# Eclipse project
.classpath
.project

Nexus One

• Nexus One Phone Details (google)

Android

• Designing for Performance
  • the System.arraycopy method is about 9x faster than a hand-coded loop on a Nexus One with the JIT.
• Multitasking in Android
  • http://android-developers.blogspot.com/2010/04/multitasking-android-way.html
• Utilities that help in the design and development of Android application user interfaces.
• Professional Android 2 Application Development - Code Download

NDK

• http://groups.google.com/group/android-ndk/

Tutorials

• NDK Tutorial by tutsplus.com + Android Beginners NDK step by step by mindtherobot.com
• Using NDK to Call C code from Android Apps

Eclipse integration

• http://www.rbgrn.net/content/348-get-your-eclipse-integrated-ndk-on
• http://codemaemo.appforce.org/2010/07/tutorial-using-eclipse-for-ndk-projects/

Accessing sensors in NDK

• http://groups.google.com/group/android-ndk/browse_thread/thread/612fbca85437edae/c43da3a2fe6a01c2?lnk=gst&q=sensor#c43da3a2fe6a01c2
• http://stackoverflow.com/questions/4200119/access-android-sensors-via-ndk
• http://stackoverflow.com/questions/1916660/need-to-read-android-sensors-really-fast
• http://developer.android.com/reference/android/app/NativeActivity.html
• http://mobilepearls.com/labs/native-android-api/STABLE-APIS.html

STRaND related

• Submission Form - stuff we submitted
• SSTL
• STRaND Nanosatellite
• s-android, Space Android: Android for Space Subsystems
• Christopher P. Bridges - Dr. Christopher P. Bridges currently works for the Astrodynamics Group at Surrey Space Centre in the University of Surrey. He teaches in dynamics and control of spacecraft and digital design with VHDL. He is currently designing and building a visual inspection payload for a two satellite mission together with EADS Astrium who is designing a microelectromechanical (MEMS) thruster. He is currently the lead research engineer for STRaND, a CubeSat-based 3U nanosatellite with advanced AOCS systems and high performance computers. He is published in mobile-agents, middleware, multi/network softcore processors, distributed satellite systems, and CubeSats. *(wrote the Telemetry App)*
• STRaND-1 Nanosatellite BBC (youtube)

Other interesting stuff

• Arduino, magnet wire, and Android combine to create poor man's NFC
• Android Open Accessory Development Kit
• Grove - ADK Dash Kit