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m1gu3
09-30-2007, 03:35 PM
Hey guys I'm trying to build a hexabot but I'm totally new in the field so I've been looking all other the internet for tutorials and guidelines to find out what to do.

I know gotta have some essential components like: servos (for movement), a controller, a receiver, code, some batteries and a way to control it (I'm thinking maybe using a PS2 or PS3 controller).

Can any of you point me in the right path to get this kind of knowledge? :confused:

Thanks in advance. :p

Alex
10-01-2007, 10:01 AM
Hey m1gu3!

We carry CrustCrawler's (http://www.crustcrawler.com/) HexCrawler HDATS Basic Kit Chassis:

http://www.trossenrobotics.com/store/p/4087-HexCrawler-HDATS.aspx

It doesn't come with the controller, but it does come with all of the servos you'll need.

Since you mentioned that you are totally new though, I'd recommend starting off with an entire kit complete with basic stamp and everything such as the one from Crustcrawler for $897:

http://www.crustcrawler.com/products/hexcrawler_hdats.php?prod=4


I don't believe they have any more of these left though:confused:, but call them up to be sure. They're changing their robots over to using the Dynamixel AX-12 servos, which we'll be carrying when they finish doing so. The Dynamixel AX-12 servos (http://www.trossenrobotics.com/store/p/5176-Dynamixel-Robot-Actuator-AX-12-.aspx) have far more potential than your standard hobby servo, so this is definitely a good move:) No word yet on when this will all happen though.


However, you mentioned that you are new to robotics, but what sort of background do you have? If you're totally new to the field and all the areas of knowledge that are required to build robots, may I recommend starting much smaller than what you are looking at now? Unless you have experience with some of the areas that robotics involves, what you are trying to accomplish as a first time robotics project will have many, many obstacles, which will involve a tremendous amount of patience:D

m1gu3
10-03-2007, 11:49 AM
hey thanks for the reply Alex, I have some background in programming so that wont be a problem at all. I just need for instance knowing what kind of components do I need. Im pretty sure to need a servo controller or receiver just checked this one that are my two main options:

1) http://www.trossenrobotics.com/store/p/3191-SSC-32-Servo-Controller.aspx
(takes up to 32 servos (believe so))

and this one from lynxmotion.com

2) http://www.lynxmotion.com/Category.aspx?CategoryID=66
(this one has connectivity to a ps2 controller what I wanted to do from the beginning and have some king of expansible processing capabilities)

- so which one of those 2 should I choose? (Am I asking to much?)

- what are the main components on a robot?

I alredy have 20 micro servos but project will one take 16 using 3 on each leg, having 6 legs. By the way Im using lego pieces to build the chassis so it would be lighter.

so what else do I need? (receivers, controllers, software, anything...:confused::confused:) I was thinking maybe controlling the hexapod from my cellphone, a 8125 using windows mobile although I want to use the ps2 controller too , that implies using Microsoft robotics studio I suppose.

maybe some cameras in the future, a motion sensor and a sound sensor. just for know lets make it move first I'd be happy if that happens.:veryhappy:

thanks for the help.

Matt
10-08-2007, 03:20 PM
Hi m1gu3,

Some of these questions are tough to answer for you unfortunately. Questions like, "What are the main components of a robot?" are very broad and pretty much require a full lesson to teach. (Not to mention no two robots are alike and have the same parts.) I suggest picking up some books on robotics or just reading through a lot of websites and forums to learn how many people are putting their projects together. You can find a lot on the internet when it comes to robotics.

The Lynxmotion controller is a very popular pick for controlling hexabots. The one we sell is a good choice if you are going to control your robot from a computer. It would stay tethered and your code would run on the computer.

The Atom Bot Board looks like it has more choices for downloading your code to the controller and letting it run autonomously. Looks like they sell manuals at Lynxmotion to teach people how to do that.

So for your project if you use one of those controllers you need your mechanical body, 18 servos, a power supply, your controller of choice, and your computer to write programs on. :)

I can't answer about controlling a robot directly from a PS2 controller or a cell phone. That's over my head unfortunately :eek:

Alex
11-13-2007, 12:30 PM
Quadcrawler posts moved to new thread:

http://forums.trossenrobotics.com/showthread.php?t=1247

m1gu3
05-07-2008, 09:33 AM
thx for the help guys, sorry haven't replied for months but been busy, very busy. got a manual from a company that does hexapods and offer their clients a complete manual on how to start assembling the robot.

also got pretty much most of the components from lynxmotion including the chassis the other day, actually I was planning to build it from lego pieces but got it aluminum made couldn't fight but getting it.

pretty much right now have:
- main board plus a separate processor
- servo controller, think it has up to 32 channels
- the chassis of course

still need:
- 16 servos, metal geared ones that I'll get from ebay
- servo brackets
- battery pack
- a way to control it

possible adaptation after is putted together:
- camera
- motion sensing
- sound sensing
- pressure sensing

appreciate any suggestions, still looking for a good programming language that helps me with this, that might be a problem because a use mac but there is dual boot.

Thanks for your help guys.

DresnerRobotics
05-07-2008, 10:48 AM
The programming language you can use usually depends on what controller you picked up. If you purchased the Basic Atom and bot board, you're pretty much stuck using it's version of basic. The Basic Atom/Bot Board does allow for control via wireless PS2 controller, LM has tons of info on setting this up.

Also just a note- be careful buying servos on ebay. Just because they're metal gear doesnt mean they're good. Specifically the Towerpro servos that are DIRT cheap on ebay, are dirt cheap for a reason. They are inaccurate, prone to failure, and have a lot of slop.

With servos you pretty much get what you pay for, personally I wouldn't build any walker with anything less than HS-645s

LinuxGuy
05-07-2008, 10:52 AM
With servos you pretty much get what you pay for, personally I wouldn't build any walker with anything less than HS-645s
I am even using three HS-645MG and three HS-475HB servos in the arm I have on W.A.L.T.E.R. now. It grew to 4DOF. :happy: I would never consider using anything less than an HS-475HB for any robotics application.

8-Dale

DresnerRobotics
05-07-2008, 11:05 AM
Personally, all future robotic endeavours for me will be using the AX-12s. The bang per buck plus easy usb connectivity is too great to pass up. Crustcrawlers is going in the right direction switching over to the Dynamixels.

LinuxGuy
05-07-2008, 12:14 PM
Personally, all future robotic endeavours for me will be using the AX-12s. The bang per buck plus easy usb connectivity is too great to pass up. Crustcrawlers is going in the right direction switching over to the Dynamixels.
They do look interesting, for sure. I can imagine your J5 using AX-12's. :) I've been thinking about eventually getting two of them to tinker with and see if I can interface them to Hammer (http://www.tincantools.com/product.php?productid=16133&cat=0&page=1&featured).

8-Dale

m1gu3
05-08-2008, 01:15 PM
:veryhappy: great input, any suggestions on what kind of boards and controllers should I use or what is recommended. In the future I want to be able to get orders to the robot from a 3rd device like a nokia n800 or a cellphone

also for the controller is there any suggestions too, there is going to be 16 servos thats got to be a good one then. I've seen boards for a considerable amount of money all over the web what can I use that is reliable but without the need of selling one of my kidneys?

Adrenalynn
05-08-2008, 01:19 PM
For large numbers of servos, can there really be a choice other than the SSC32?

Run, don't walk, and buy it here:

http://www.trossenrobotics.com/store/p/3191-SSC-32-Servo-Controller.aspx

m1gu3
05-08-2008, 01:45 PM
true about the running :veryhappy:, how about that mini ITX board just saw and add on the front page can I hook my components into it? if so whats the energy toll on that? how many batteries would I need and so on?...

how about this -> hammer kit (http://www.tincantools.com/product.php?productid=16142&cat=250&page=1) looks promising how extensible is this. eventhough have no idea is there might be something missing for the project.

Adrenalynn
05-08-2008, 01:59 PM
Robotguy can answer all your questions about the Hammer. He's a regular and I'm sure will be along momentarily.

I've gone to the PicoITX for on-bot processing power. It uses about 13w, and I power it from the broad-range power supply, PicoATX. The PicoITX is miniscule in size compared to the miniITX, but packs a 1Ghz processor and up to a couple gig of memory... It's a Full PC platform.

http://www.via.com.tw/en/products/mainboards/motherboards.jsp?motherboard_id=472

http://www.e-itx.com/m3-atx.html

Alex
05-08-2008, 03:10 PM
Anybody ever play around with these:

http://tech.yostengineering.com/servoFolder/

They're more geared towards animatronics, but I can totally see them being used in other robotic applications

m1gu3
05-08-2008, 03:17 PM
found a board relatively cheap, for about 80 bucks, decent specs. with this board being a computer mother board and all that I assume plugin a phidget board (think so) here is the :cool: link (http://www.logicsupply.com/products/d201gly2a) to the actual board. actually doesn't this make the robot a walking computer but it still needs a hard-drive to store information that might me a hassle...SSD drives still expensive...Adrenalynn you mind sharing your experiencia and basic hardware using the pico-itx?

using a mainboard like this I think gets rid of programming in the computer and then going to the robot because the actuall robot is a computer, I'm still concerned about the hard-drive. :confused:

Adrenalynn
05-08-2008, 03:21 PM
I'd be concerned about the current draw on that board myself.

I use a laptop hard drive with a custom made triple-shock-insulation system.

Basically three frames with rubber gromets working as all-axis dampers where the bolts go in. I'll shoot some photos at some point.

You aren't really planning on mounting all this on a hexapod, right?

DresnerRobotics
05-08-2008, 03:51 PM
I also have a good amount of experience with the pico-itx, so any specific questions you have just let me know.

Word of caution though, you're looking at an additional battery, hard drive, PicoPSU and the pico-itx + its cables and interface dongles... it does add a good amount of weight. On a hexapod you're limited in your payload capacity so to be honest, I would use nothing less than HSR-5990TGs on any DOF that is vertically supporting the payload (tibia, vFemur) if you want to implement an onboard PC. Any lesser servos wont be able to support the additional weight.

LinuxGuy
05-08-2008, 04:42 PM
how about this -> hammer kit (http://www.tincantools.com/product.php?productid=16142&cat=250&page=1) looks promising how extensible is this. eventhough have no idea is there might be something missing for the project.
What do you mean as extensible? Hammer (http://www.tincantools.com/product.php?productid=16133&cat=0&page=1&featured) runs Linux, so if you have never used that operating system, I don't think you want to use Hammer (http://www.tincantools.com/product.php?productid=16133&cat=0&page=1&featured).

If you are familar with Linux and have used it, then Hammer (http://www.tincantools.com/product.php?productid=16133&cat=0&page=1&featured) might be fine for what you want to do. There is definitely a learning curve you will have to go through though. You will be writing your own software for Hammer (http://www.tincantools.com/product.php?productid=16133&cat=0&page=1&featured) to do what you want to do, so be aware of this.

8-Dale

m1gu3
05-12-2008, 01:43 PM
Sorry for the late response guys, I've come to a couple of decisions on this project that think they are the most acurate to achieve something.

1. stick to the basics, just make the thing move a couple inches will be ok, for the first couple of days
2. It will be controlled from my computer, I've seen a couple of controllers that can do that, think so. for that matter I'll use the SSC-32 SERVO CONTROLLER (http://www.trossenrobotics.com/store/p/3191-SSC-32-Servo-Controller.aspx)from lynxmotion.

Also that controller has a couple of modes that I'm interested in, wonder if they can be switched on the run, including the ps2 controller one.

Thanks for your help guys, also found a source of inspiration among the forum is Zenta's phoenix that is pretty much what I want to accomplish on my project. Expect some pictures as soonest I get a couple of screws together and some wires so it would look like something not a bunch on pieces of metal and plastic.

Thaks again for your help.