forum.TeamFREDNET.org

by **tristancho** » Thu 2009 Aug 13 3:58 am

I mean... You can do this in the regolith that way. It has to be using other approaches.
Joshua

by **Enric** » Tue 2009 Aug 18 6:32 am

Hi guys,

I am back from holidays and I will continue collaborating with Team Frednet ASAP. Good work!

by **scasey** » Tue 2009 Aug 18 11:53 am

Hi Enric - hope you had a restful holiday. Good to see people getting re-engaged in the program.

SC

by **tristancho** » Tue 2009 Aug 18 4:13 pm

Welcome Enric again,
You can see many news since you start holidays. See this article called "Hamster balls and lunar hoppers: meet the X Prize teams":
http://www.newscientist.com/gallery/dn1 ... the-moon/9

Best regards,
Joshua

by **boone** » Tue 2009 Aug 18 6:49 pm

On the remote chance you haven't thought of it:
To see how cold the shield (and window) can handle, you could dunk the Picorover in liquid nitrogen (boiling point of −196°C). Your university physics department probably has some.

by **tristancho** » Tue 2009 Aug 18 11:56 pm

Yeah, sure. But as an Open Source team I try to do my experiments using homemade equipment. Any one in the worl has to be able to repeat my experiments because are open. If you have a refrigerator and an oven you can reproduce the experiment and have similar results. That's the wonder of the Open Source approach.

Personally I am not so interested in very low temperatures. The Picorover will has a thermal subsystem able to transfer heat from the Core to the Shield or heat the Core if necessary. Low temperatures only will happen in the lunar night and I think it is better turn off the robot and wait for the next day. Using embedded components make feasible survive the lunar night as long as they are off. The only critical component is the battery and it was tested by Astrobotics team. see at:
http://www.youtube.com/watch?v=bqfDZnKecto

Best regards,
Joshua

by **boone** » Fri 2009 Aug 28 7:24 pm

Even if there's a thermal subsystem, it seems like common sense to me that it should be stress tested (although the moon may be easier than liquid nitrogen because of the lack of convection and the insulating properties of regolith).

At the very least, test it in dry ice. You can buy that at the supermarket or a gas supply store (at least in the U.S. you can).

I don't think being open source is a very good reason to avoid a test. It's not like everybody has a Picorover on hand for stress tests! I would find replicating a cold test easier than building a duplicate Picorover!

My $.02.

by **tristancho** » Sat 2009 Aug 29 10:41 am

Sure!
We must do this stress test at the end but before that, we have to complete internal components and then do the test.

This kind of experiments are not easy and I want be sure we do once and well done.
Thanks again,
Joshua

by **tristancho** » Thu 2009 Sep 17 6:01 pm

Sorry for our silence but we are preparing the near-space test of many Picorover components in the First Team FREDNET balloon flight.

Two months ago I started a series of thermal and vacuum tests. The final result will be recorder in the final test: the integration test, what consist of a Picorover inside the Hoven at 150ºC runing and communicating with my laptop.

Up to now I am preparing a new light shield of only 54.5 grams for this last test.

You can see details in my drafts.
Best,
Joshua

by **tristancho** » Tue 2009 Sep 29 12:38 pm

BTW, see a simulation of a home made launcher for the PicoRover.
http://www.youtube.com/watch?v=vRyv2jAqf_s
Best,
Joshua

by **Humble** » Wed 2009 Sep 30 12:42 am

Cool one ...

What kind of tool have you been using to run this simulation?

by **tristancho** » Thu 2009 Oct 01 5:20 am

Hi,
My brother built this tool. The simulation and the User Interface is made in Visual Basic and the OpenGL is controlled by C++.
Thanks to Juan M. for this excellent work.
My best,
Joshua

by **AndersFeder** » Thu 2009 Oct 01 9:14 am

Cool, Joshua. Is it open source by any chance?

by **tristancho** » Fri 2009 Oct 02 7:13 pm

AndersFeder wrote:Cool, Joshua. Is it open source by any chance?

I am working in the validation of this simulator. I can upload a version of the code in the Launchpad if I have access to. I can't remember where is the link to the Launchpad...
Best,
Joshua

by **Enric** » Wed 2009 Oct 07 7:13 am

Nice work Joshua!

Enric.

by **tristancho** » Wed 2009 Oct 07 2:33 pm

You welcome, Enric.
Best,
Joshua

by **tristancho** » Wed 2009 Oct 07 2:51 pm

Hi all,
Every time I build a new prototype of the PicoRover I spend many time in the same part: THE CROWN; because it is a piece designed for this prototype and it has to be very light so it requires many work. This is the case of this critical part of the new PicoRover (<100 grams), This crown is made of thermal aluminum and it will be able to move the Picorover inside the Oven at 150 ºC. Using a servo I make a mark every 2 degrees so it will produce 180 teeths. I use a pinion with a teeth module of z=1.75 mm.

See my draft for details about the construction process.

My best,
Joshua

by **tristancho** » Sat 2009 Oct 10 4:59 pm

List of parts:
26.8 grams Bearing shield half
27.7 grams Window shield half
12.3 grams Crown
05.4 grams Hair ring
03.0 grams Spikes and hair
75.2 grams TOTAL

by **tristancho** » Sun 2009 Oct 18 8:59 am

This is the Team FREDNET stand in the UPC university of the PicoRover.
Best,
Joshua

by **tristancho** » Tue 2009 Nov 03 6:52 pm

Other interview for Team FREDNET in Catalonyan:
03/Nov/2009 Catalunya radio interview in the Cabaret electric program
http://www.catradio.cat/reproductor/audio.htm?ID=387149
Joshua

by **boone** » Tue 2009 Nov 10 8:21 pm

A thought: since the crown is causing you trouble, OPEN SOURCE IT! That sounds like the perfect problem for a bunch of tweak-happy mechanical engineers. Maybe it could be an evolving CAD file? (I don't know anything about mechanical engineering; I just read about this approach in PopSci and want to pass it on.)

To pull it off, you'd have to write up some design requirements, but then you could take some work off your shoulders AND get a superior part.

My $.02

by **tristancho** » Wed 2009 Nov 11 10:14 am

Oh, of course.
But at the end i found a better way to build this crazy crown from a toy steel made train rail. Pictures will be able soon.
Thanks!
Joshua

by **tristancho** » Wed 2009 Nov 11 10:22 am

Other news paper coverage for the PicoRover (Sorry, is in Catalonian) it is in the www.adn.es news paper coverage in page 15. Youcan see the picture of Picorover shield weight.
http://www.adn.es/pdf/ADN-2009-11-10-BCN.pdf
Best,
Joshua

by **scasey** » Wed 2009 Nov 11 2:33 pm

Nice write-up - congratulations. There's no mention of Team FREDNET though...

:/

by **tristancho** » Wed 2009 Nov 11 3:18 pm

Oh! they only mention GLXP and they forgot our team competitor name! Arggg.
Best,
Joshua

by **tristancho** » Wed 2009 Nov 25 10:20 am

BTW,
In a few moments: how to build a real PicoRover live ... or watch on-demand videos related to this open hardware project if you were late.
http://www.teamfrednet.org/picoroverlive.html

My best,
Joshua

by **scasey** » Wed 2009 Nov 25 1:37 pm

Joshua,

I think you should advertise a broadcast schedule for the week so people will know when to tune-in.

I'm getting the 'offline' color bars!

SC

by **alexc** » Wed 2009 Nov 25 2:12 pm

I missed it too

It would be great with announcement a day in advance or if not possible, when it happens via email or twitter, which gives the info in real time.

Here is a list of recordings that can be watched on demand:
http://livestream.com/frednetballoon/folder

Joshua, can you change the title for some of them to describe the topic of the video or alternatively post it here? I could then also post on the team blog

By the way, you can also watch the live shows on livestream: http://livestream.com/frednetballoon you can then have the chat box open at the same time.

by **tristancho** » Wed 2009 Nov 25 6:18 pm

Oh yes,
We have to have a procedure for this kind of activities and we need a commond place to broadcast this events. For the PicoRover build process I don't have a predefined schedule, it depends how much work I have this day. I think, in this sense, the important part is not a live show if there is not feedback but on-demand videos is important.

Alex mentioned Twiter but I don't know what is this but thanks for the link. This is what I am looking for.

I imagine a place with a schedule where Team FREDNET people broadcast the experiments, on-going build process, test events, etc.

My best,
Joshua

by **alexc** » Thu 2009 Nov 26 6:37 am

tristancho wrote:Alex mentioned Twiter but I don't know what is

Twitter can be used for many things, but in this case you can send out short messages (max 140 characters) and people who follow you will get notified within a few minutes. It's like sending an SMS to a distribution list via the web. The messages are recorded in a time line, see for example the Team FREDNET time line.

by **tristancho** » Thu 2009 Nov 26 6:46 am

Oh Alex,
It looks useful. How can I inform to Team FREDNET Twiter about my building activities?
My best,
Joshua

by **alexc** » Thu 2009 Nov 26 7:05 am

Actually, all you have to do is create a user account on http://twitter.com and tell us the user name. I can then follow you and whenever you post an update it will appear in my incoming twitter-feed. I can then "re-tweet" the message so that everyone who follows the @teamfrednet account will also get notified.

You can post messages via the twitter web interface or I think you can even do it from the Livestream broadcast interface so you don't need to install any application.

by **tristancho** » Thu 2009 Nov 26 8:04 am

Right,
I will try to learn it in the Livestream application.
As per schedule, Livestream has a schedule. I have update this schedule with two possible events.

Thanks a lot!
Joshua

by **tristancho** » Thu 2009 Nov 26 8:22 am

scasey wrote:Joshua,

I think you should advertise a broadcast schedule for the week so people will know when to tune-in.

I'm getting the 'offline' color bars!

SC

Yes,
Here you have my schedule.
http://livestream.com/frednetballoon/
My best,
Joshua

by **tristancho** » Fri 2009 Dec 11 7:22 pm

Hi all,
After 1 year of development we have the results of the PicoRover in the sand.

See this video in livestream channel:
http://www.livestream.com/frednetballoo ... 10b375d50e

And also in YouTube:
http://www.youtube.com/watch?v=xKduyap2ugI

Also you may compare theoretical results with experimental results in the Feasibility Study

Enjoy it!
Joshua

by **tristancho** » Thu 2009 Dec 17 3:22 pm

We lost the WikiSat Balloon Recovery System in the Launch #1 but this time we try to attempt a second chance with a validated code of the WBRS written by Anders Feders. I validated the program and it works very well in my car so I hope it will work in the balloon as well.

This time we take pictures. This is what the WBRS is watching now:

My best,
Joshua

by **tristancho** » Tue 2010 Mar 16 12:38 pm

This week, PicoRover Group has grown with a few members between students, teachers and involved people. For this reason we have done a press conference in order to show our two models, the Lunar one and the Earth one.

We have got a very good response. See a list of coverages or videos:
http://wiki.teamfrednet.org/index.php/User:Tristancho

Go Team FREDNET!

My best,
Joshua Tristancho

by **tristancho** » Tue 2010 Mar 16 12:39 pm

by **Enric** » Mon 2010 Apr 26 3:55 am

Last days I was learning how to use Photoshop and in a moment of distraction I created a "funny" poster includying the Picorover into an original NASA photo (and also the Team Frednet logo).

Enric.

by **Enric** » Mon 2010 Apr 26 3:57 am

Well, I've found the first mistake, it's teamfrednet.org, not teamfrednet.com :oops:

by **tristancho** » Mon 2010 Apr 26 4:34 am

Hi Enric,
Never mind. We have this domain as well.

Tomorrow we have a PicoRover conference:
Conference

My best,
Joshua Tristancho

by **tristancho** » Mon 2010 Apr 26 5:56 pm

Is a femto Rover feasible?
Yes, it is and I will show this tomorrow in the FME conference.

My best,
Joshua Tristancho