Need help with microcontroller selection

[gibsongtr874]

I am considering purchasing the Axon microconroller for my first robot, would that be a good choice? What kind of programing does it use or does it come with a program? I am new to this but very interested just not sure where to start. Also considering the Basic Stamp by Paralax, please help.

[jamort]

This is a question that can have so many choices after i tell you what i kno...
1.) The axon is one of the best microcontrollers your going to buy....
2.) basic is really easy to program, but has limits...
3.)c and c++ are a little or maybe a lot (depends on person) harder to learn but it has less limits then basic...

the axon is programmed in c.... it be the way to go if your up to learning the programming

[Metal Slug 2]

Why not start with an (arduino-based) Roboduino?

The roboduino is a great start to any first-time robotics project and many more advanced ones.  The programming interface is easy to learn, has tons of libraries/example codes and no external programmer is needed to program the board.  With the use of a few jumperwires, you can utilize the power of the many different arduino shields available.  You can purchase the roboduino here: http://curiousinventor.com/kits/roboduino

A bonus is that you can choose a pre-soldered board or a kit, depending on whether you want to solder or not.  The roboduino uses an Atmega128 microcontroller from Atmel.

Lastly, it is possible to program the roboduino with other software such as AVR Studio 4, however an external programmer (in this case an AVRISP MK2 programmer) will be required for such a thing.

oh, and one more thing:  you could also start with the $50 robot, it uses an Atmega8.  Here is a link for it:  http://www.societyofrobots.com/step_by_step_robot.shtml

[Kylepowers]

Hi i might seem stupid asking this question. But when you use a microcontroller do you need anything else like motor controllers and such. Or is all you need is the microcontroller. Second what is a good controller for a robot with multi limbs and many sensors and possable voice control? thanks im new but wanting to start my own robot project.

[galannthegreat]

The microcontroller controls everything, you need something to handle the raw voltage and higher currents. If you try controlling your motors from a microcontroller pin you'll end up frying the pin, or even worse the back EMF (generated by all inductor type devices) could destroy your microcontroller.

Here's an example of a good driver to control 2 motors (perfect for differential drive):
http://www.solarbotics.com/cad/products/k_cmd/

[Kylepowers]

Ok so if i get a microcontroller. I still need a motor controller for drive motors and a servo controller for servos. But what is a good starting microcontroller the axon or the Roboduino : Freeduino for Robotics (Arduino Compatible)?

[galannthegreat]

For motors, yes, you need a motor driver, but for servos there are 3 wires (generally), one for raw power, one for ground, and for control. To control the servo you can use a microcontroller pin with no problems, such as the harsh effects that a motor would generate when directly connected to a microcontroller. Check out the $50 robot, it'll help you out with this.

http://www.societyofrobots.com/step_by_step_robot.shtml

[Kylepowers]

Ok cool now my question is should which microcontroller should i get. from the two listed in my last post

[galannthegreat]

As a personal preference for starting, I chose an Arduino. I found it to be very easy to learn how to program and create some very cool projects. For robotics the Roboduino is a good way because it has the standard 3 pin headers we like so much (makes it easy to plug in servos and sensors).

gibsongtr874, I'd recommend this one aswell. When I started I found the Arduino (get the Roboduino, as it is nice for robotics) to be the easiest for me to learn how program with.

[billhowl]

But Roboduino only have 13 digital IO & 6 analog IO pins, if you need to control a robot with multi limbs and many sensors, Axon will be preference as it have 55 IO pins. If you need to program with Arduino IDE, you can put the arduino bootloader into Axon and it will able to work with Arduino IDE.

[Razor Concepts]

But Roboduino only have 13 digital IO & 6 analog IO pins, if you need to control a robot with multi limbs and many sensors, Axon will be preference as it have 55 IO pins. If you need to program with Arduino IDE, you can put the arduino bootloader into Axon and it will able to work with Arduino IDE.

Better to think of it as 19 digital IO pins, 6 of which are capable of analog input (not IO!). The "analog" pins can be configured as digital IO

[Kylepowers]

Alright im going to go with the axon just because i like the fact that i can build and add more to it like sensors and arms. Next question on the axon is what motor controller do you recommend for use with it and where do i connect it to the axon?

[galannthegreat]

Well, it depends on the current that the motor will draw and the running voltage of the motors you want to use. The idea I suggested before will be able to drive up 46 volts (actually only about 25 with the current regulator  that comes with the kit), and be able to control current draws of up to 2A per motor (safely) with spikes up to 4A.

So, if you plan on using small motors (such as the ones I like from Solarbotics), it should not be a problem.
(http://www.solarbotics.com/motors_accessories/gear_motors/)

But if you want to use motors with higher requirements you need controllers that can handle the demands. In which case something along the lines of a Sabertooth will do more than suffice, though it is expensive.
(http://www.robotshop.ca/dimension-engineering-sabertooth-2x25-6.html)

But those are not your only options, choose a motor and verify specs then choose a motor controller/driver.

[Kylepowers]

Well also is there a way to interconnect microcontrollers. for instance if i were to build the microsontroller from the $50 robot tutorial but i want more servos/senors/motors to run off it. could  i build three of them and then link them together so they could talk to each other and share sensors and such. Or do you know how to make a microcontroller for doing but with more inputs and out puts using that as a bases. If so what IC would be the  best something like that thank you. Also on the IC what dose each pin do like i see pc 1-7 pb 1-7 oc1a and things like that what pins can sensors go on what pins do servos go on and what pins dose the power go on. How do i tell this and how do i tell what is analog and didgetal. thanks