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Forlorn Foundry
06-01-2010, 08:43 PM
Hello everyone--

I just found out about Mech Warfare and I have to say I'm completely taken with it. :D

I've had some experience with robots... I was on the First team back in high school, and I competed in Battlebots twice. I have my own machine shop and do a lot of aluminum casting but I don't know anything about programming and codes.

I've been looking at the lynxmotion BRAT with the 645 servos, from what I have read it seems to be a good springboard for someone new to programming. I think that having a working code that I can play with as I learn will be very helpful.

Am I on the right track in thinking that this is a good start for someone new to programming? Is BASIC Atom good for the first timer?

Any more info or advice would be greatly appreciated!

Bryan

lnxfergy
06-01-2010, 09:01 PM
This is still a bit of a can of worms, and I'm sure to be jumped on for this response, but:

The Lynxmotion kits are phenomenal for getting you going fast, great documentation/tutorials and the code is all there and ready to go.

That said, we've still yet to see a BRAT really compete in Mech Warfare. I know Miss Alignment had serious connection issues this year, but even then, they had upgraded to what I believe were 5990 servos. It's still a major point of contention whether a 645 BRAT can actually perform as necessary.

I've you are just getting started, a quad might be a better choice for the first year -- a biped is a tough project, and with the inclusion of qualification rounds, we've raised the bar quite a bit just to get on the ladder.

-Fergs

gdubb2
06-01-2010, 09:15 PM
Hey Bryan,
Welcome to the group. Great to have another combat veteran coming to this side of things. I competed in Battlebots, and Robogames for many years with my middleweights Maggot and Botfly.

You will find as many opinions as there are types of robots. Which is best, I believe to be which ever you feel the most comfortable with as far as the hardware and software goes. As Fergs said, the lynxmotion kits are great, but there are others that might be more versatile if not better. The Bioloid system is wonderfully versatile, and has a lot of support here in the forums.

If you must learn programming as you go, it leaves it wide open. You can learn whichever is needed, and away you go.

Good luck
Gary

Upgrayd
06-01-2010, 09:45 PM
The feasibility of a Lynxmotion BRAT mech is still up for debate. Even in the past year we have seen quite a few BRAT mech projects come and go.

I believe that it is technically possible to build a walking BRAT with all the required Mech gear but you really will be fighting an up hill battle...

My recommendation for a new comer would be looking into a quad or hex robot with either 2 or 3 degrees of freedom in the legs.

darkback2
06-02-2010, 12:22 AM
Advice for a newbie is to go with a quad, and since you have no bias look at an arbotix. Check out the starter kit and the commander. I think the lynxmotion stuff is really good, but AX-12s will probably end up saving you money in burned out servos in the long run.

If you do go with lynxmotion/hobby servos, then I would suggest a 3 dof quad using SES brackets and an SSC-32 coupled with a xbee for control. You could also use a ps2 controller and the wireless receiver that lynxmotion offers.

If I could start all over again, the AX-12/arbotix route is probably the way I would go.

If you are dead set on a biped, then you could still go with an arbotix, but then things get expensive in a hurry. In the case that a biped brat is what you want then go with 5990s. Warchild has highly modified legs, I hardly think you could call warchild a brat anymore. :)

Hope this helps, and I can't wait to see you stomping around the city.

DB

Forlorn Foundry
06-02-2010, 09:13 PM
Thanks for the imput everyone

I have been looking more at the bioloid kit and it seems like it's going to be far superior to the BRAT. The Ax-12 is such a great servo for the money.

This is what I'm thinking now:

Bioloid beginner kit
6 Ax-12's
Arbotix Robo controller starter kit
Arbotix commander

Does this look like a good start?
Is there anything I should have on this list and don't?
What will it take to get a simple biped running remotely using the Arbotix commander?

Looks like I'm in for a huge challenge but I'm up for it :happy:

Thanks for all the help everyone

Bryan

DresnerRobotics
06-02-2010, 09:58 PM
If you're going the bioloid route, and using an Arbotix, don't bother with the actual kit. Just pick up a comprehensive frame set + however many ax-12s you'll need. The kits come with stuff you don't need if you're using an arbotix. I would however suggest picking up an appropriate 3s lipo pack and charger (I'll have new chargers in the catalog tomorrow).

Welcome to Mech Warfare btw! If you have any questions about the competition, feel free to ask!

lnxfergy
06-02-2010, 10:12 PM
Bioloid beginner kit
6 Ax-12's
Arbotix Robo controller starter kit
Arbotix commander

Does this look like a good start?
Is there anything I should have on this list and don't?

I second Tyberius suggestion: dump the starter kit and pick up the comprehensive frame kit + your servos. You'll get a lot better selection of frame parts, wires, and screws with the frame kit. The one other thing I would suggest is getting a 12V Power Brick (http://www.trossenrobotics.com/p/power-supply-12vdc-5a.aspx) and an SMPS2Dynamixel (http://www.trossenrobotics.com/store/p/5886-SMPS2Dynamixel-Adapter.aspx) to make bench powering the bot real easy.


What will it take to get a simple biped running remotely using the Arbotix commander?

It's not terribly difficult to get capture some poses, and string them together, you can see a video of one of my bots doing that:
YouTube- Reaver Walking
I'm hoping to have Biped support in our NUKE IK package later this summer (beta video below)
YouTube- Reaver2 First Walk

-Fergs

Forlorn Foundry
06-07-2010, 08:34 PM
Thanks again guys

I'm looking at buying a new PC specifically for this robot. Is there anything special I should be looking for? Can I get away with a low end desktop or am I going to need something more high end? Any suggestions would be helpful.

Bryan

Stobs
06-08-2010, 12:06 AM
What's the purpose for getting the new pc? Are you going to be running a program that requires more capacity in some manner than the one you're using? Do you want to go to a different OS (if so why not do a dual boot on your current one)? Or do you just want to get a dedicated system for your robotics endeavors? If the later is the reason then I'd recommend getting the best mid-range performing unit you can afford - today's high-end machines are in next month's bargain bin, almost literally, so stay away from them unless you just want to blow some bucks or you have a legitimate need. If you're going to get into 3D design and animations then get the best Mac you can afford or go for a RAM heavy PC (I'd shop your RAM upgrades with manufacturer's packages and after-purchase upgrades). You can do anything text-based (not desktop publishing; literally text or simple word processing) on a netbook easily enough.

.Stobs

Forlorn Foundry
06-08-2010, 08:39 PM
At this time I only have a Mac so to be able to run more software I'm looking for PC that will be dedicated to my Mech. I need something small and easy to transport, but still powerful enough to run all the programing and other software I'll need. If I could get all that for $500 or under it would make me a happy man:happy:. Eventually I'd like to build it into a small mock cockpit but that's a long way off--just getting it to walk is going to be hard enough.:)

Bryan

Stobs
06-08-2010, 10:21 PM
What Mac do you have?

Forlorn Foundry
06-09-2010, 04:45 PM
I have a mac mini.

Stobs
06-09-2010, 05:42 PM
I'm no longer that familiar with Mac's (although my next computer purchase will be for one), but if you want to economize and you're running OS X on an intel-based mini, you may consider running windows via Boot Camp (you'd have to double check to see if it's already installed on your system or not), or some similar program. Here's a step-by-step for a WinXP install (http://macxp.furbism.com/), an overview of a Vista install (http://trevinchow.com/blog/2007/10/19/mac-mini-running-vista-media-center/) and one for a Win7 install (http://news.cnet.com/8301-13860_3-10151680-56.html). Since you were pondering about getting a low-end desktop this might be a more cost-effective solution for you. Besides, the more you save on getting adequate computing power the more you'll have to spend on your bot! ;)

.Stobs

darkback2
06-09-2010, 07:03 PM
I am. Mac user and use bootcamp when I absolutely need windows. It is definitely the way to go if you have the space on your hard drive.

Forlorn Foundry
06-09-2010, 07:49 PM
I love my mac I wouldn't trade it for anything but I'm also thinking that having a dedicated robot computer will leave the mac open for my wife to use while I play with robots for hours on end:D

DresnerRobotics
06-09-2010, 09:44 PM
There are some pretty nice intel i3 core laptops to be had around the $500 range, I just picked one up to run as a dedicated 'mobile bot computer'.

I'm not anti mac or anything, but it seems to be an uphill battle for robotics use as the majority of stuff out there is being developed to run natively on windows or linux.

Stobs
06-09-2010, 10:46 PM
FWIW I agree; I think Mac's are awesome machines but the technical sciences aren't typically "it's" forte. I don't know that I'd be looking at a Mac for my next system if I didn't already have a fairly decent PC-form laptop. On the flip side of that though, is I'm pretty sick and tired of my HP's breaking down and loosing keypads or having problems with the internal a/c adapter breaking, being the main reason I'm jumping ship. Just need to make sure I can run AutoCad on it first though, but I'm a few months away from needing to figure that out - never know what might happen in the computing world in three or four months! :)

.Stobs

zoomkat
06-09-2010, 11:11 PM
I use a Toshiba laptop that is ~5 years old and is what I'm using now. Every once in a while Walmart will put a full size laptop on sale for $299 (Acer or similar brand). Netbooks run about the same in price. Looked at getting a linux box ~10 years ago, but quickly found out that apparently 90% of the time people spend piddling with linux itself leaving only 10% of the time for an actual project.

JonHylands
06-10-2010, 08:21 AM
Looked at getting a linux box ~10 years ago, but quickly found out that apparently 90% of the time people spend piddling with linux itself leaving only 10% of the time for an actual project.

That was true ten years ago, but is no longer true today. Ubuntu installs out of the box on most reasonable hardware, and it requires no more work than Windows. I was a die-hard Windows user since Windows 3, and I still use XP for certain things, but my main development machine now dual boots XP and Ubuntu, and the only reason I boot into XP is to play games.

I do run VMware, and have an XP install in there, where I run my CAD software, my PCB design software, and my email client, all of which are Windows-only software.

- Jon

jes1510
06-10-2010, 08:34 AM
I use a Toshiba laptop that is ~5 years old and is what I'm using now. Every once in a while Walmart will put a full size laptop on sale for $299 (Acer or similar brand). Netbooks run about the same in price. Looked at getting a linux box ~10 years ago, but quickly found out that apparently 90% of the time people spend piddling with linux itself leaving only 10% of the time for an actual project.

Jon's right about this. Ten years ago, you may have had to do some work just to get the system up and running. This isn't the case anymore. I actually find that Linux is easier to maintain and use than Windows. Heck, you can even download a live CD and boot from that to try it out without having to install anything.

Robot Dude
06-11-2010, 09:18 AM
I can accept the criticism that the BRAT has never successfully competed in the event. We made a pretty impressive attempt at it. I seriously thought we got it close enough for any experienced builder to finish it off. We have everything nailed except adding the target plates. We illustrated that the system would handle the weight of the additional required components. And this was with analog 645 servos.


http://www.youtube.com/watch?v=3N5CJ_QPjQI

However I'm a little confused by the attitude. Rather than acknowledge what success the BRAT has shown the original poster is immediately directed towards a quad, hex, or some bioloid bot, which the later has also not been shown to sucessfully competed as a biped mech. I'm not looking for a flame war, just trying to politely make a point. The BRAT is a good minimal platform for a biped Mech.

lnxfergy
06-11-2010, 09:39 AM
However I'm a little confused by the attitude. Rather than acknowledge what success the BRAT has shown the original poster is immediately directed towards a quad, hex, or some bioloid bot, which the later has also not proved capable of powering a biped mech. I'm not looking for a flame war, just trying to politely make a point.

As for a bioloid biped not having proven itself - Odin took 3rd in 2010.

As for why I tend to direct people towards quads at first -- we actually want to see bots show up that work. I'd personally rather have 2 working quads than 30 failed bipeds. It's no fun to sit around and not be able to actually compete. If it's your first time competing, you've got enough to learn without dealing with the added complexity of balancing a biped.

I did post some videos of a bioloid biped -- and I sort of regret having done that. My recommendation is typicall to start with a quad -- after you've mastered the programming/control/reliability required for MW, move onto a biped.

-Fergs

Robot Dude
06-11-2010, 10:09 AM
As for a bioloid biped not having proven itself - Odin took 3rd in 2010.

Hey now thats progress!


As for why I tend to direct people towards quads at first -- we actually want to see bots show up that work. I'd personally rather have 2 working quads than 30 failed bipeds. It's no fun to sit around and not be able to actually compete. If it's your first time competing, you've got enough to learn without dealing with the added complexity of balancing a biped.

It's cool, no problem... The thing that gets me is there is very little difference between the two platforms. The 645 and the AX-12 are similar in specs. The plastic brackets are about the same weight as our aluminum SES brackets. The SSC-32 with it's group move function and our walking gait program already written makes it easy to get walking. The bioloid servos have some useful features, but they are not required to make a functional mech. The way I see it the majority of folks here just like the bioloid system and that ok too. Again not trying to start a fight. Just trying to add some diversity to the sport. I make cool bots, and I like the Mech War scene. Peace! Jim

Connor
06-11-2010, 10:19 AM
I can accept the criticism that the BRAT has never successfully competed in the event. We made a pretty impressive attempt at it. I seriously thought we got it close enough for any experienced builder to finish it off. We have everything nailed except adding the target plates. We illustrated that the system would handle the weight of the additional required components. And this was with analog 645 servos.

However I'm a little confused by the attitude. Rather than acknowledge what success the BRAT has shown the original poster is immediately directed towards a quad, hex, or some bioloid bot, which the later has also not been shown to sucessfully competed as a biped mech. I'm not looking for a flame war, just trying to politely make a point. The BRAT is a good minimal platform for a biped Mech.

I've bit my tongue long enough on this topic.

Jim, In Servo magazine, your running a ad that clearly states "Introducing the Hunchback! The world's first completely functional biped Mech Warrior!" I sent you a email the first time I saw this ad telling you that wasn't true. Shadow Scout (My Mech, based on the Scout frame) was the first Biped in the 2009 Robogames. He was in the arena, with target plates, he fired his guns, and it took a few steps (but fell, ALOT.) There is even some video of him firing his guns in the arena. I also pointed out, that the Pilot is the Mech Warrior, the machine is a Mech, or Battle Mech.

Just because you all built a Brat Biped that can shuffle walk around and shoot BB's and remote operate through the camera doesn't mean it's a fully functional Mech. You MUST have the target plates AND the transponder in place.. I've YET to see that, and I would say, you would even need to compete in the event. With that being said.. We were all concerned with how affective the Brat could be with the payload for Mech Warfare, and questioned weather or not HS-645MG's were enough.. I personally still question it. My Scout had 5990's and 5995's and still could barely work. Shuffle walking isn't going to be easy on the floor either. It's textured, and caused some issues for the Brat Based Mech Miss Alignment (which I think used 5990's). They had to spend time tweaking out the walking gait on site.

For 2010 RG, I ditched the LM Erector Set and Hobby servos and opted for a Bioloid, competed, and won 3rd place. My Bioloid is pretty much stock except for the battery and the ArbotiX Controller. Odin, became the World's First Fully Functional Bioloid based Biped Mech, and the First Fully Function Arbotix Based Biped Mech. The reason we don't recommend the brat, is it's not the best platform to start with. Bipeds are hard to compete with.. Going to be even harder in 2011. Quads are easier and get people in the door.

Thanks, Connor

Adam
06-11-2010, 10:31 AM
The 645 and the AX-12 are similar in specs.

That's a stretch. The AX-12 is rated for twice the voltage and has almost twice the torque. Not to mention the many programmable features.

DresnerRobotics
06-11-2010, 10:41 AM
On the same accord, a $800~ quadruped using an SSC-32 and HS-645MGs beat a $12,000 high end Robotis based mech this year (2nd Amendment vs Giger), and beat it well.

Quads are inherently easier to get up and running for beginners than any type of biped, brats included, for this type of competition. The largest reason there is due to their exponentially higher payload and stability.

Robot Dude
06-11-2010, 11:00 AM
I used the information I had available to me and did inquire with a few higher ups there at Trossen before placing that ad. I was ensured it was not a problem. I'm sorry you took offence to it. You seem to think I have my finger in the pulse of Mech Warfare, but I do not. I simply made a commitment to Andrew to try and help him get bipeds to the event. Whether I was successful or not isn't the point here. I was trying to help Andy and the SPORT. It's not my fault you couldn't get your Scout based mech working. Congrats on your 3rd place victory.

On the 645 / AX-12 comparison. Zenta found the 645 to be stronger. He said "I have the bioloid comp kit, and the first I did was to test its torque. And I must say I was very disapointed. The holding torque was great, around 16 kg. But the running/load torque was not good at all, I measured between 6 - 7,5 kg. The Hitec 645MG was even better!"
http://www.lynxmotion.net/viewtopic.php?p=44536#p44536

Here is a similar finding.
http://sites.google.com/site/robotsaustralia/ax-12dynamixelinformation

Like I said from the beginning I don't want to fight. But I can see it's futile. So I'm bowing out of this forum. I will continues to support Andy and his Mech War project behind the scene though. Serioulsy I wish you all well in your robotic endevours. Peace! Jim

Upgrayd
06-11-2010, 11:32 AM
In my mind I believe a BRAT would be able to compete in Mech Warfare. But... compete is a very loose word to use here. the term 'compete' implies being able to carry all the required gear, walk around, shoot, and navigate via camera. It does not account for performance such as speed, maneuverability, payload, ect.

Many people come to this forum after seeing some coverage from the event bright eyed and looking for advice on a platform to use to get started. And many of the people seem to be attracted to the BRAT because it is a relatively low cost kit that is ready to run. It also has the biped cool factor going for it.

However... I strongly believe most of these same people would be sorely disappointed if they were to show up with their mech only to have a match against a quad that can literally walk circles around the BRAT.

Quads are generally the recommended due to their inherent stability, speed, payload, maneuverability options, ease of construction, ease of programming, and most importantly.... the support we have on this forum with the Arbotix and Pypose software.

We are suggesting quads and ax-12 powered bots because they provide a platform that allows you to learn and will also 'grow' with you if you wish to advance to a biped.

master_of_robots
06-11-2010, 11:53 AM
Like I said from the beginning I don't want to fight. But I can see it's futile. So I'm bowing out of this forum. I will continues to support Andy and his Mech War project behind the scene though. Serioulsy I wish you all well in your robotic endevours. Peace! Jim

Dude...there's no need to get all upset and leave. I thought the whole point to Mech Warfare is to try and build the best robot and to actually FIGHT to see which one truly is the best. I doubt anyone's robots have turned out exactly how they imagined it. You keep what you like, and figure out how to fix the "bugs".

If you know that people have a certain expectation of the Brat, then wrench on it until it does meet that high water mark. I've never been successful at anything that I gave up on.

Jim, you have a wealth of knowlege that has been really helpful on these forums. Don't leave...:veryhappy:

Adam
06-11-2010, 12:22 PM
There is no doubt that a SES biped could compete. The servos and brackets are not the issue. It's a bit of a shame that Lynxmotion-based bots have not been better represented at MW.

lnxfergy
06-11-2010, 12:27 PM
There is no doubt that a SES biped could compete. The servos and brackets are not the issue. It's a bit of a shame that Lynxmotion-based bots have not been better represented at MW.

I'm actually amazed we didn't see any hexapods this year -- I had figured we'd see a lot of people throw a gun&camera on top of their phoenix and show up. There are just so many of them out there. I'm not entirely sure how well the PS2 controller would hold up for competition, but I seem to recall Andrew drove his phoenix around at RG2009 without too much difficulty...

-Fergs

helishaun
06-11-2010, 09:26 PM
I used a PS2 controller in the humanoid events and experienced some control issues. In all of the events I was within 5ft of the robot with no obstructions. I don't know how it would work out for you guys in the Mech Warfare tent.

lnxfergy
06-11-2010, 09:38 PM
I used a PS2 controller in the humanoid events and experienced some control issues. In all of the events I was within 5ft of the robot with no obstructions. I don't know how it would work out for you guys in the Mech Warfare tent.

Wireless is definitely a problem at RG. I'm frankly hesitant to recommend any setup. That said, I recall that the PS2 controller actually did connect when I saw it trying to work -- which is quite a bit better than most of the people I saw trying to use Wifi for control.

In the end though, builders have to assume there will be data loss -- and have to design for it. That means using digital radios -- with a decent packeting structure, including checksumming and recovery. The XBEE radios we tend to recommend already do this (and if you're using the ArbotiX libraries, there is an added level of checksumming and garbage tossing on top of the hardware resend capability).

-Fergs