5hz GPS from Spark Fun

[LukeZ]

Just in case anyone missed it - this looks like a real gem.

The new EB-85A from ETek is a 5Hz update GPS receiver. Super sensitive, extremely configurable, this is the GPS unit we've been dreaming of. The baud rate is adjustable from 4800 to 115200bps, the output rate is adjustable from 5 down to 1Hz, the accuracy is 2.6m with DGPS. It's pretty nifty.

Click here. (http://www.sparkfun.com/commerce/product_info.php?products_id=8266)


Luke

[Tom Harper]

Luke,

I bought one - just had to!

Haven't fired it up yet. But, I did get some .22 F supercaps to keep the settings alive.

SparkFun did not have the female connectors when I bought mine. That's OK since I will cut the cable in half and install the large connectors I use as standard. Also I intend to mount the .22F capacitor (and a diode) in the cable rather than on the apps board.

Tom

[Unterhausen]

I posted that here a few weeks ago. Looks very nice. I never realized how much processing those things have to do, but this unit beats the 1hz units that seem to deliver a second old data.

[Blue Sky]

Mr. RC-Cam bought a bulk purchase of EB85-A's and is offering them for 79.00 ea.,
assuming he has any left.
He also has useful programing info on his RC-Cam forum.
http://www.rc-cam.com/forum/index.php?showtopic=1855&st=0

-Dave

[LukeZ]

Wee! Guess I'm falling behind here. I used to read every post in every thread in this forum every single day. Did that since the very beginning, but the last couple months I've had to really slack as "real" life is starting to take over. Sorry I posted old info. :o

Dave, thanks for letting me know Mr. RC-Cam is selling them, and cheaper than SparkFun too!


Luke

[Blue Sky]

Wee! Guess I'm falling behind here. I used to read every post in every thread in this forum every single day. Did that since the very beginning, but the last couple months I've had to really slack as "real" life is starting to take over. Sorry I posted old info. :o

Dave, thanks for letting me know Mr. RC-Cam is selling them, and cheaper than SparkFun too!


Luke

It can't hurt to have another heads up.
I'm sure other people missed it too.
My "real" life has also been interfering with my real life.
Fortunately I have DSL at the office. Still, little time to build, program, test, fly etc.

-Dave

[Unterhausen]

I was surprised that my thread got no notice. Didn't mean my post as criticism.

[LukeZ]

I was surprised that my thread got no notice. Didn't mean my post as criticism.No criticism taken! Guess this one got noticed because of my effervescent charm. :D ;) :rolleyes:


Luke

[Jack Crossfire]

After bad experiences with the LIS3LV02DQ and the Micromag3, I'm very skeptical of everything the sparkfun guy says. His stuff looks really neat and his copy writing makes you salivate, but in reality his stuff tends to be real flimsy and have lots of hidden bugs.

At 5Hz it probably isn't as accurate as the 1Hz models. The accuracy seems to be a limitation of the number of satellite pings it averages in each result.

[XJet]

At 5Hz it probably isn't as accurate as the 1Hz models. The accuracy seems to be a limitation of the number of satellite pings it averages in each result.

That's been my observation, the accuracy is around +/- 3m, whereas 1Hz GPS units like the Larsen IQ regularly provide a +/- 1.5m accuracy.

We're about to start some flight testing in our UAVs to see how well they perform in a real-world environment.

[Unterhausen]

It makes life a lot easier to be getting the data at a higher rate. But there are obviously tradeoffs. If you are moving, you are probably better off getting less stale data and correcting it using a Bayesian Filter.

[thomasscherrer]

the EB85 sometimes give a wrong postion 500-800m off
this can be triggered with : too fast climb/desent rates, loops or rools !

when it is in "wrong" mode it needs a stable constant height for a while
to restore,
even after landing and at total stop:
I have seen the distance to home count down from 800m to 20m in 2mins !

also when changing height and direction too fast the SPEED readout
can goto ZERO for several sec !

the EM406 GPS have newer failed on those mentioned cases,
but it lack on the fast position update.
and is several sec behind actual position, so when navigation fast
it is causing problems to navigate without over steering.

[Tom Harper]

Good information - thanks!

[thomasscherrer]

maybe I should also state that flying nice and calm will make the EB85 perform as expected, great and fast.

[LukeZ]

Hmm, that is interesting to know. Thanks for posting.

[XJet]

We've been using these GPS units and haven't noticed this particular problem -- mind you, our UAVs aren't programmed to do loops and rolls :-)