This page describes experiments carried out to create an embedded video processing unit based on the OMAP3530 application processor from Texas Instruments using Gumstix Overo COMs. This is one branch of the Embedded Video Processing and Radio Unit project. Logbook is on the talk page.
- Capture video from one or more cameras
- Compress and multiplex the videos with telemetry into a single transport stream suitable for transmission over the air
- Process incoming telcommands
First flight on amateur rocket
The objectives of this flight are:
- To test the Gumstix Overo Fire under high acceleration (6g)
- To capture images and/or video during the flight
We learned about an opportunity to fly onboard an amateur rocket (up to 3 km high). Flight will take place on October 3, 2010. Time is very short so we will be focusing on getting the Gumstix Overo Fire up and running, and have it record video during the flight. No real time video downlink.
- After power on system boots Linux
- WiFi and Bluetooth are switched off
- Video capture script begins
gst-launch -v v4l2src num-buffers=18000 (TBC) ! image/jpeg,width=640,height=480,framerate=30/1 !\ avimux ! filesink location="video-%d.avi" 1> stdout-%d.log 2> stderr-%d.log
OS version: Angstrom 2010.7-test-20100923
We have about 7 watts at our disposal.
Gumstix Overo Fire (WiFi and BT off) + Tobi expansion board + Logitech Webcam Pro 9000 consumes less than 500 mA at 5 VDC
The weight of electronics, camera, battery and wires not including the mounting hardware is approximately 200 grams.
Results & Conclusions
- We worked very well as a team
- Gumstix Overo Fire survived a crash landing from 500 meters (TBC if still working properly)
- USB interface on Gusmtix Overo Fire is too slow for HD (even in MJPG mode). Max throughput appears to be around 10-15 Mbps.
- For future UVC setups, a guvcview-like app to control all camera settings will be very useful.
- The hacked USB OTG interface eliminating the powered hub did not work well. After a while, the pipeline would stop due to a device I/O error
- The simple Gstreamer pipeline does not seem to be sufficient. While recording, every now and then there is a "jump" in the video suggesting that there is some performance issue somewhere (disk I/O, buffering?)
- When using SD cards, remember to add a piece of tape securing the card to the socket!
Damage due to crash landing
| Get Gumstix Overo Fire up and running
|Update image and boot from microSD||100%|
|Flash updated image to NAND|
| Power consumption (with and without WiFi and BT)
Measurements done with Overo Fire on the Summit board.
- Overo: Setup and Programming on Gumstix developer site
- I/O, connectors & cabling
- WiFi and BT SoC specs (local copy).
- Setting up Wifi on Gumstix Overo Fire
- PIXHAWK – Many useful BeagleBoard and Gumstix Overo COM related things. In particular, they seem to use similar cameras to those I got with the Leopard board, see http://pixhawk.ethz.ch/wiki/pixhawk_camera_competition
- Minimal, quick booting Gumstix image and other resources
- http://specialcomp.com/index.htm – Nice acrylic cases
- OMAP Power Management – Embedded Linux Wiki.
- Gumstix users wiki: Overo Wifi
- Gumstix users wiki: Creating an Ad-hoc Network
- Gumstix users wiki: Bluetooth
- Gumstix Overo: Connector Overview & Design Information. See in particular Signals PDF.
- 2010.09.06: Gumstix Overo Fire on a rocket
- 2010.09.12: Gumstix Overo Fire booting from microSD card
- 2010.09.13: Kernel panic, accidental downgrade and working webcam
- 2010.09.18: Gumstix Overo Fire status and re-scoping the project
- 2010.09.23: Video recorder update
- 2010.09.24: A few bits and pieces for the onboard video recorder
- 2010.09.28: Disabling the WiFi on the Gumstix Overo Fire
- 2010.09.28: Expected video quality during the rocket flight
- 2010.10.01: Pre-flight mockup
- 2010.10.01: Rocket integration
- 2010.10.01: Arduino flight computer
- 2010.10.06: Successful flight and a crash landing
- 2010.09.12: Gumstix Overo Fire booting from microSD
- 2010.09.14: OpenGL Demos on Gumstix Overo Fire
- 2010.09.28: Disable WiFi on the Gumstix Overo Fire
- 2010.09.30: Arduino flight computer firing the igniter (related video)
- 2010.09.30: Video Recorder Test Setup (Gumstix Overo Fire)
- 2010.09.30: Assembled rocket interior - Gumstix Overo Fire video recorder
- 2010.10.04: Arduino and Gumstix Overo Fire on a rocket
- 2010.10.04: Rocket inspection after crash landing and recovery
Complete YouTube playlist