Society of Robots - Robot Forum

General Misc => Misc => Topic started by: Equium Duo on March 26, 2012, 12:44:05 PM

Title: What is the best starter board?
Post by: Equium Duo on March 26, 2012, 12:44:05 PM
Hi,
Been a while since I was playing with robots, anyway I was wondering what might be the best starter arduino board to go for? I think I had a duemilinoavae (spelling?) or something a few years ago. I'd love an axon II and hopefully that will be possible down the lone, but it's a bit pricey for me right now. Any reccomendations? i want something like an axon series but with not quite so many features for testing and developing sub modules in our planned project.

Kindest Regards
Chris
Title: Re: What is the best starter board?
Post by: joe61 on March 26, 2012, 01:09:00 PM
What features would you like to have?
Title: Re: What is the best starter board?
Post by: Soeren on March 26, 2012, 05:02:42 PM
Hi,

[...] i want something like an axon series but with not quite so many features for testing and developing sub modules in our planned project.
Features doesn't hurt, you can just leave them be for starters.
Take a look at this kick-a$$ 80MHz Arduino like board (http://www.digilentinc.com/Products/Detail.cfm?NavPath=2,892,893&Prod=CHIPKIT-UNO32) running circles around the competition for a measly $27  :)
Title: Re: What is the best starter board?
Post by: Equium Duo on March 27, 2012, 06:27:03 AM
I've just re-read that sentecne and it is confusing. Basically I'd like the functionality of the axon, without the need for the computing power/number of I/O's as the axon. An example of my intended use:

I want to make a robot with 6x legs. But I want to develop a leg for the robot, an axon would be required for the full robot, but for just something to quickly prototype a leg I'd use something a bit simpler and cheaper.

Does that make sense?
Title: Re: What is the best starter board?
Post by: joe61 on March 27, 2012, 07:34:06 AM
One of these (http://www.adafruit.com/products/296) might be suitable for what you're looking for, and you can program it with a regular USB cable. I believe you can use the Arduino environment to program them as well, with a little extra work.

You could also make up a board with the same chip the Axon uses if you're up for that.

Joe
Title: Re: What is the best starter board?
Post by: Soeren on March 27, 2012, 09:29:25 PM
Hi,

I've just re-read that sentecne and it is confusing.
Which sentence is that?


I want to make a robot with 6x legs. But I want to develop a leg for the robot, an axon would be required for the full robot, but for just something to quickly prototype a leg I'd use something a bit simpler and cheaper.

Does that make sense?
Not really.
I guess you may think, that it's easier to learn/use a simple controller, but actually, you'd just have more to learn, as you cannot apply all you've learned to the "full version", unless you use the very same controller, so starting simple might be starting complicated.

You shouldn't fear neither speed nor "features". If you don't intend to use eg. SPI initially (or later), just don't, the controller doesn't force you to learn all the peripherals that you don't need, so just pretend they're not there (until you need them).

If you only need to control say 3 servos initially, you can do that with eg. a PICAXE, a BASIC Stamp or whatever, but then you'll have to start from scratch when you move to a larger controller.

With eg. the 83 lines of a ChipKit32 you can just ignore the 80 pins and control the same 3 servos with the same amount of work as on any other controller - and it will then be simple to extend that code to 18 servos when you're done with testing the first leg.


But hey, it's your money and your time spend learning one or two systems, so it's your decision :)
Title: Re: What is the best starter board?
Post by: Gertlex on March 27, 2012, 11:09:03 PM
I want to make a robot with 6x legs. But I want to develop a leg for the robot, an axon would be required for the full robot, but for just something to quickly prototype a leg I'd use something a bit simpler and cheaper.

Does that make sense?

I'm a convert to using digital servos, namely the dynamixel brand servos... You can control a large number from a single UART port with either a bit of additional circuitry or programming.  And prototyping is easy with the bioloid frame kit, or an actual bioloid kit.  There's also a few dynamixel brand simple controllers, but I've not used those.  (The full spectrum of products of this sort can be seen here (http://www.trossenrobotics.com/c/robotis-dynamixel-robot-servos.aspx))

For experimenting with leg prototyping with regular servos, something like this (http://www.pololu.com/catalog/product/207) could be interfaced directly with a computer via usb serial adapter.  (Ok, I'm too lazy to double check, but I think its possible with that board) More generally, my point is that you can start with a servo controller, and then later have the Axon or other MCU send commands to the servo controller which does the job of maintaining the PWM signal for each servo.