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View Full Version : Trying to build a tank.....proffesional science board question?



Bulslayer85
03-12-2012, 01:51 PM
Gave up on flyer idea and going to build a tank...yes an actual tank that will shoot stuff with a paint ball gun.....dont ask. My question is how can u hook up a battery to the parallax science board?

I think that board is best for what i want to do, tank will have tracks and ill need powerful enough motors. only two boards i have are the science board and the bo-bot one that i might use for the turret but otherwise doesn't fit well into this project.

I'm planning on using like a small motorcycle battery or something like that, not sure, I'm going to bring this up to my Robotics teacher today but was wondering if anyone else had simple solutions to this.

turbosupra
03-12-2012, 02:05 PM
I use the propeller in my car.

I've never used the prop science board, but I assume it is propeller powered and that's why you posted in this forum? I just use the 5v regulator connected directly to the 11 to 14vDC system the car has (depending on if the alternator is rotating or not) . I haven't ever had an issue with the regulator not being able to bleed off enough current to maintain 5v. Of course it gets stepped down from 5v to 3.3v after that for the propeller. You could even use a 9v regulator before the 5v regulator to be thorough.

12v battery --> 9v --> 5v --> 3.3v --> propeller

Bulslayer85
03-12-2012, 02:35 PM
yes, using prop chip cause it can handle more complex coding, science board supports the functions i need along with a big enough breadboard for some of the extra sensors i plan on getting. The board supports a 7 - 12 VDC power connection, so i guess more specificly can i wire a connection directly from the battery if its 7 to 12 volts?

turbosupra
03-12-2012, 03:34 PM
If it's a true 12v or less sure, if not I would check the spec of the regulator they are using. If it is going to have an alternator, such as my car or a motorcycle or even a tractor which all use 12vdc systems, it will see more than 12v.

If it were me, I would use a 9v regulator to cover my butt or a current limiting resistor with a 12v zener as a fail safe "pop off valve". I think the inexpensive 9v regulator is the simplest choice.



yes, using prop chip cause it can handle more complex coding, science board supports the functions i need along with a big enough breadboard for some of the extra sensors i plan on getting. The board supports a 7 - 12 VDC power connection, so i guess more specificly can i wire a connection directly from the battery if its 7 to 12 volts?

Duane Degn
03-12-2012, 06:06 PM
only two boards i have are the science board and the bo-bot one

Like turbosupra, I'm not familiar with a Propeller board called the "science board". Apparently it has a breadboard. The only Propeller board I know of that comes with a breadboard (that has been released), is the Propeller Demo Board.

Could you elaborate a bit about which board you have?

Do you know what kind of treads you plan to use? There are a couple of options I'm familiar with.

The least expensive option are these Tamiya tank treads (http://www.sparkfun.com/products/321). You'll need a couple of motors to power them. You could use continuous rotation servos (forum member, Amanda has done this) or some other geared motors (http://www.sparkfun.com/products/319).

Another option is the Rover 5 (http://www.sparkfun.com/products/10336) chassis. I'm liking the Rover 5 more now that I've figured out how to use its encoders (http://forums.parallax.com/showthread.php?130797-Mecanum-Wheeled-Robot-with-Machine-Vision&p=1078740&viewfull=1#post1078740). The Rover 5 comes with four motors.

Vex makes some treads (http://www.vexrobotics.com/276-2168.html). I have a set but I haven't made a bot to use them yet. I think they look and feel pretty good. Again, you'll need a set of geared motors to power them.

Lynxmotion makes and sells some really nice looking tracks (http://www.lynxmotion.com/c-94-tracks.aspx). Amanda has also used these.

You mentioned you have a BOE-Bot board. Does this mean you also have a BOE-Bot? If so, a good place to start would be to learn to control the BOE-Bot with your Propeller board.

I'm a fan of treaded vehicles and hope to build one myself soon. I look forward to watching your progress.

Circuitsoft
03-12-2012, 07:20 PM
Have you seen the Wild Thumper platform SparkFun just released? It's not on treads, but it has 6 wheels on independent suspensions with a fair amount of travel. As a demo, they made a remote-controlled potato canon, and it seems to handle varying terrains quite well.

Publison
03-12-2012, 07:34 PM
I believe the OP might be referring to the PPDB, (science board). :

http://www.parallax.com/StoreSearchResults/tabid/768/txtSearch/PPDB/List/0/SortField/4/ProductID/515/Default.aspx

I (http://www.parallax.com/StoreSearchResults/tabid/768/txtSearch/PPDB/List/0/SortField/4/ProductID/515/Default.aspx)t sounds like he has a BOE also.

Duane Degn
03-12-2012, 08:27 PM
I believe the OP might be referring to the PPDB, (science board). :

http://www.parallax.com/StoreSearchResults/tabid/768/txtSearch/PPDB/List/0/SortField/4/ProductID/515/Default.aspx

I (http://www.parallax.com/StoreSearchResults/tabid/768/txtSearch/PPDB/List/0/SortField/4/ProductID/515/Default.aspx)t sounds like he has a BOE also.

Thanks Publison. I have two within three feet of where I'm sitting and still didn't think of it when trying to think of Propeller boards with a breadboard.

I don't think the PPDB comes to mind when I think of controlling a robot. It would need to be a pretty big robot to fit one of those on/in it.

Bulslayer85
03-13-2012, 10:01 PM
yeah Publison that would be the one, lol, sorry for name mix up, i have that and the Board of Education that came with the boe bot. I recently got the treads for the boe bot so im going to use that for now as money is a bit tight and i cant get all the materials i need for the larger one but i would eventually like to use the bigger board sense it has more room on its bread board and can support bigger motors.

the-new-guy
03-13-2012, 10:45 PM
If you are going to mount it directly to the 'bot, the loose connections of a breadboard don't sound like a good idea to me. Also, why not just use a seperate power supply and a few transistors?

P.S.: Pf, a paintball gun? I say, if you're gonna do something stupid, y'do it REALLY STUPID!!! BAZOOKAAAA!!!

Bulslayer85
03-14-2012, 02:05 PM
um well to be honest i'm just using the paint ball gun as merely a refference as mounting a real gun like my shot gun might put me in a bad way with the local police and as seeing that i will want this robot to eventually act as a sort of guard dog for my home (experimenting with concept) things tend to work better when it doesn't go right to killing things. And on the note of power to the board, i have an idea as to how to do it but im going to ask my Robotics Professor today about it. He has a project as well with the same propeller board i plan to use only his robot just maps gps points and doesnt shoot anything lol.

Bulslayer85
03-14-2012, 02:34 PM
And as far as size, yes the final version will be big, take an M1A1 Abrams and shrink to a scale of 2 feet long by about 1 1/2 wide body, with the turret head i have no clue till i build it, going to try to keep it proportional. And in case everyone is still wondering why, answer is im not just a hobbyist, i am aiming for a degree in robot engineering and plan to work for a company like the one that makes the Talon.

Duane Degn
03-14-2012, 02:51 PM
And as far as size, yes the final version will be big, take an M1A1 Abrams and shrink to a scale of 2 feet long by about 1 1/2 wide body

Have you thought about what treads you'll use?

There are some treaded robots on Let's Make Robots that use bicycle chain with other materials to make the track.

Gordon likes to reuse treads from toy tanks.

Plus there are the options I listed earlier.

I hope you keep us up to date on your progress.

Bulslayer85
03-14-2012, 06:51 PM
Yah thats pretty much was what i was thinking Duane, i found a DIY page on making em out of bike chain and some small pvc pipe, probably the best route since i can adjust the length that way, I'll probably do four wheels and a motor for each, the tracks can be an add on but i dont really need it to be tracked right now.

for now im just going to use my boe bot to build the program, i got the tank tracks for it so i should have those today, i cant build the bigger one yet but thats ultimatley the goal of the project. Im mostly experimenting with developing advanced atominess behavior to limit the robots dependance on a human pilot in combat, (trying to make it think for its self better), i really dont even need to mount a real gun on it, could easily build with using a LED to represent firing a gun but it sounded more fun with the paint ball gun.