Archive for the Ground Category

NEWS SPLASH!

Posted in Air, Android, Arduino, Ground, Hardware, Sea, Sensing on March 19, 2013 by asteriondaedalus

Waterproof mobile phones available between $70 single core and $140 dual core. POSTSCRIPT Read later article.

water proof phone

Android 2 odd on the single cores and Android 4 odd on the dual cores.

This will compliment the waterproof servos I have ordered for the Rock Crawler:

hitec-waterproof-servo-large

Or the waterproof brushless motor and esc:

trac3349_550

(*pist* normal brushless motors can run under water BUT may need to do things to them to make them last longer)

So a bluetooth module on one serial port of the:

31138

And an XBee/Snap on the other serial port and viola, Perfect waterproof system … well once I sort out how to waterproof the little board above.

Still, for projects that don’t need the sensors and only want to drive servos or ESC then a bluetooth XBee module on the:

1-340x340

So many possibilities and you can mix and match without pesky wires.

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Visual odometry – optical flow

Posted in Ground, Hardware, Sensing, Vision on June 18, 2012 by asteriondaedalus

Well.  I lost heart after buying a couple of mouse sensors to find that buying a separate lens was possible from china … but then diydrone/3drobots helped out by putting a mouse sensor and a lens together.  In fact, they matched the lens and mounted them so was cheaper all up to bin the raw mouse sensor and buy the unit (or two of them in fact – very popular).

Along with an SPI interface I can now add optical flow/visual odometry input to my IMU/AHRS for the rock crawler.   I opted for that, initially, since it will likely be prone to wheels spinning etc so encoders on the wheels would not help as they would generate errors where the wheels turned but the chassis stayed put.

Mind you, an encoder on each wheel, and one on each drive shaft (to detect wheel spin etc) might be an interesting project but alas no open source code base for it 😉

Plenty of code comes with the kit from diydrones.  The thing is working the sensor into the IMU code – just another sensor to fuse.

optical-flow-1

Yes, that is my medicine in the background – no really, I was laid up after major abdominal surgery and they prescribed Stout.

Going wireless

Posted in Ground, Software on May 22, 2012 by asteriondaedalus

At home recuperating after surgery, so I can spend a couple of hours sitting tinkering so I don’t go stir crazy.

Previously I mentioned I got hold of a DFRobot Bluetooth dongle for my DFRobot Romeo (All-In-One).  It decided to try the basic example to see if the bluetooth dongle on my laptop would work with it.

The usual trips and stumbles.  I had upgraded to 1.0 of arduino.cc and forgot to set the board type properly then had to discover buried in the narratives the reminder to take the Bluetooth dongle off the Romeo when programming as it clashes with the onboard USB … yadda.

The only nuisance then was the built in terminal in the IDE which is a bit clunky.  I got around this with a download of Tera Term VT.

The final hurdle was the need to manually connect to the COM port despite having set the flag for auto-connect.

So, more (or less) a plug-n-play.

The Pièce de résistance, I bombed the Romeo with the Dining Philosopher’s example from the QP site (using the event driven kernel for the Arduino) … viola!  Bluetooth serial works with RT event driven kernel.

vt

Next step will be to get a connection going with one of the Android gadgets using Amarino.

PS.  On a hunch I went looking on the Android App Market and (sure enough) I have downloaded a couple of bluetooth terminal programs to see if I can use the tablet instead of the laptop for some of the terminal driven experiments … stay tuned.

PPS. Yeah HA! er, sorry.  Paired my Acer A500 with the DFRomeo running with bluetooth dongle and within a couple of seconds was able to control the app running on the Arduino with the tablet through BlueTerm.  Unlike the laptop, the tablet autoconnects and stays connected even when tablet goes to sleep – whereas the laptop would drop the connection when sleeping and require the nuisance manual connection when awoken.

So busy with work but here is updates to date

Posted in Chase That Dog!!, Ground, Prototyping, Vision on December 3, 2011 by asteriondaedalus

ARDrone now in possession.  Second hand from a pal who has moved to China for work.  Good luck D!

I am buying a house so stocked up on a few things in meantime.  9DOF Razer etc.

I got a DF Bluetooth for the ROMEO as the USB Host board covered too much around the edges.  The initial experiments will be from the laptop any way (which now sports dual boot Ubuntu and Windoze).

First experiments I am working towards are using IP WebCam (on Android) and Cambozola to produce something like the functionality of WOWWee Rovio (basic video streaming and remote control) before moving onto using OpenCV to experiment with flow optics.  OpenCV is slowly being ported (under open source by TI – see here and here otherwise go here otherwise here) to the OMAP devices to accelerate it on the ARM side of the world – so no need to rush to install on Android just yet.

[QualCOMM Snapdragon S2 and above has an already tuned fast CV library (go here). Pity my phones are S1 😦 ]

Android phone (acting as video streaming service) will be taped to front of indoor carriage as there is no real need to put any more dings in the ARDrone (just yet).

The neat thing about IP WebCam, from an integration point of view, it could just as easily be used as a video stream to a application on the phone that is serving the video.  A nice way of decoupling the functionality.

Also grabbed a MEGA IO shield on sale.  It has an SD card pinout (I already have the SD card breakout) and an XBEE site.  This will be great then for experimenting with OpenMAV protocol for moving to the outdoor carriage.  It will also be used for the prototyping work – so the more capable boards don’t get handled as much OR charred if something goes wrong 😉