swerve drive with arduino mega 2560

[asid61]

Instead of starting with a swerve drive in Arduino, try working through the tutorials first; it'll be a lot of help.

[beckster1999]

https://drive.google.com/file/d/0B7L...ew?usp=sharing

this will hopefully work

[beckster1999]

i have to start with a swerve drive and arduino, the project was to make a swerve drive bot and i only need to do the programming now. i didn't choose the assignment, plus i spen翶spent too long cadding it for ages until i was the only person left who hadn't graduated and now I needa finish it on my own.

[ajlapp]

This is an exceptional challenge...

We can help, but we can't do everything.

Have you done the following:?

1. Loaded an example program onto the arduino, i.e. blink
2. Verified that the example program is running

You have to at least achieve this before attempting to write any robot control code.

Also, it sounds like you're using a programmer tool. You shouldn't need this...just a USB cable and the Arduino software.

[ajlapp]

Also, I can't see from the image if you have a steering sensor installed?

I presume you have it located on top of the steering module...but I can't tell.

Is this true? What sensor is it?

[beckster1999]

it doesn't have any sensors on it yet, i will probably add them soon, but i kinda wanna figure out how to code it first since I don't know C++ at all yet.

[ajlapp]

Have you done the following:?

1. Loaded an example program onto the arduino, i.e. blink
2. Verified that the example program is running

[beckster1999]

i don't think so. im not sure how

[ajlapp]

http://lmgtfy.com/?q=how+to+load+code+onto+my+arduino

Check out the first link.

Arduino is supposed to be easy....so follow their simple guide and get some example code loaded. Then we can discuss doing something like controlling a speed controller etc.

[beckster1999]

i tried the one called blink and it seemed to work

[beckster1999]

i have to go until monday since I don't have class again until then, but thanks for your help so far

[ajlapp]

Perfect.

Now you can investigate the "Servo" example. It shows you how to send commands to a hobby servo...this is similar to sending commands to speed controller.

I don't recall off the top of my head if it'll just work or if it needs some tweaks...regardless, it'll send PWM commands out a pin on the arduino and make your speed controller request voltage be sent to your motors.

[Alan Anderson]

Originally Posted by beckster1999

it doesn't have any sensors on it yet, i will probably add them soon, but i kinda wanna figure out how to code it first...

You can't write code for hardware that is not yet defined. Anthony's questions require an answer before you can get useful help: what kind of sensor is it? Where is it mounted?

[Mike Bortfeldt]

Becky,

First off, I think this drive system is an great choice for a first swerve system. Having the steering modules linked together, as well as speed, will make things much easier from a control aspect. Because of this, I wouldn't start with any sensors. They are not needed to be able to drive around, and for someone relatively new to programming, this will make things much easier. I would use a two axis joystick model, where the forward/backwards motion drives the robot, and the side to side motion controls the speed of turning. Sensors can be added later once you get it driving if you want to have more (or more interesting) control.

As others have said, you will need to be able to generate PWM signals for the speed controllers and the Arduino servo library has that capability. But before we get to that, one important question comes to mind. Have you thought about how you are going to control this? What type of operater station do you have and how will it communicate with the Mega? Wireless? Wired (tethered?) Somehow you will need to get the information to the mega on what you want it to do, and that will add another layer of complexity to your system depending on the communications you want to use.

I would initially like to suggest an idea that could make this project much easier (no programming). Do you have access to an RC style transmitter/receiver? Maybe something like this? Using an RC style controller would allow you to eliminate the mega and just control the speed controllers directly. IIRC, the talons should be able to take a standard servo style input. Just a thought. There may be other better ideas out there, but this happened to come to mind. Would this be a possibility?

Mike

[asid61]

Originally Posted by Mike Bortfeldt

Becky,

First off, I think this drive system is an great choice for a first swerve system. Having the steering modules linked together, as well as speed, will make things much easier from a control aspect. Because of this, I wouldn't start with any sensors. They are not needed to be able to drive around, and for someone relatively new to programming, this will make things much easier. I would use a two axis joystick model, where the forward/backwards motion drives the robot, and the side to side motion controls the speed of turning. Sensors can be added later once you get it driving if you want to have more (or more interesting) control.

As others have said, you will need to be able to generate PWM signals for the speed controllers and the Arduino servo library has that capability. But before we get to that, one important question comes to mind. Have you thought about how you are going to control this? What type of operater station do you have and how will it communicate with the Mega? Wireless? Wired (tethered?) Somehow you will need to get the information to the mega on what you want it to do, and that will add another layer of complexity to your system depending on the communications you want to use.

I would initially like to suggest an idea that could make this project much easier (no programming). Do you have access to an RC style transmitter/receiver? Maybe something like this? Using an RC style controller would allow you to eliminate the mega and just control the speed controllers directly. IIRC, the talons should be able to take a standard servo style input. Just a thought. There may be other better ideas out there, but this happened to come to mind. Would this be a possibility?

Mike

For a swerve drive I would think manipulating motors directly would be difficult. It could be possible with crab drive. However, the Mega has a pulseIn() function one can use to read the PWM coming out of an RC transmitter, so perhaps that could be used instead of a wifi link or something for controls.