RC India

Hello every one !! Does any one in this forum had successfully built an ardurover? If yes, please respond. I am planning to build one but struck with some doubts. Thank you..

I haven't build one. But it can't be more difficult than ArduCopter, right? What kind of doubts do you have?

just ask your doubts here, ardurovers are not much complicated anyway.

1. I am thinking of using a normal metal chassis without any suspension. If i mount apm on the chassis even with any foam there will be vibrations which might affect the working of board right ?
2. I will be using skid steering method with brushed motors and brushed escs with brake function and flysky t6. If i use channel 3 for throttle how can i apply breaks to stop the motion of the car?
These are my doubts as of now. Thank you  :)

1] Vibrations don't affect the working of the board unless it is trying to stabilize the platform (like in a multirotor). A rover doesn't need stabilization as it is a ground vehicle. The APM just helps in doing autonomous missions.

2] Instead of brushed ESCs, use a dual-motor-driver. That way it'll be much easier to implement all kinds of motions. You can use an arduino between the APM and the motor-driver. If you want to use ESCs, you'll need to use elevon mixing for steering+reversing and throttle for controlling the speed.

What is the stall current of your motors? 

http://www.ebay.in/itm/4-Wheel-Robotic-Platform-V2-0-4x4-Drive-DIY-with-DC-gear-motor-Chasis-Wheels-/231636281537?hash=item35ee9928c1:g:5A8AAOSwu4BVqSUK This is the kit i am going to use. They had not mentioned the specs except the RPM.
Why do i need an arduino inbetween? Won't APM takecare of all those things if i select skid steering connections?

If you are using ESCs without 'reverse' function then you won't be able to reverse the rover or rotate it on a spot. If you are okay with that then you don't need a motor driver or an arduino.

Those motors have a stall current of 1A. If you want 'reverse' and 'spot-rotation' capabilities, all you need is a low cost L298 motor driver board.

Are you planning to use it indoors or out?

Thank you for your reply sir. Mostly i will be using it indoor. I am already having a l293d motor driver and do u have any circuit diagram for the connections?

That kit has 4 motors with a stall current of 1A each. The L293D won't be able to handle it. You'll need a L298 board. If you want to use it in 4-wheel-drive mode, you'll need two L298 boards.

l298 are cheap sold at Robu.in at 300

robo mart sells them at  :Rs: 249. The first time I placed an order with them, I received a message saying 'Your order is packed', just 20 minutes after checkout! An hour later they had shipped my products. I received the package a day later! They send you a message for every step of the packing, shipping and delivery process!

I will be using elevator channel for camera pan and tilt. So reversing is not possibe with channel 3 and i won't require it. Is braking is possible with the throttle channel?

I think there is some missing info here which will cause a lot of head scratching on the op's part :P I dont think that the APM directly controls a generic motor driver/H-Bridge (L298/L293D). The APM will output PWM encoded signal that a ESC understands. So you will need another MCU(Arduino is the easy choice) to decode those signals and run the motors through the H-Bridge ICs. Try googling "Arduino RC input" to figure this bit out. In my case I built a discrete H-Bridge as my motors were 20A stall. Putting it simply: You need something between the APM and the motor driver ICs if you are using the ardurover code.

A suggestion: Use throttle channel for camera pan and tilt. Use the elevator channel to run the motors. I found this made more sense as i could keep the camera tilt at a comfortable angle without holding on to the stick.

L298n supports direct PWN in.

@Gagan, I said PWM encoded. That is digital DATA coming out of the APM, not 0%-100% duty signal PWM signal meant to directly drive the motors. In layman's term APM outputs the same type of data that a RC Rx outputs to run ESCs. You can think of an ESC as a combination of an Arduino and L293D driver. Many ESCs use an ATmega8 as the microcontroller and discrete MOSFETs to control the motors.
To clarify the OP's doubts:
Let me assume you are going to use the L298. The L298 only understands PWM signals, not encoded data. Please google and read up on how to run motors using the l298/l293d chips. The APM puts out a train of pulses that instructs a ESC to run the motors. Here you need an Arduino to READ IN this input and then OUTPUT a normal PWM signal from its PWM capable pins. You hook this(PWM from ARDUINO) to the enable pin of the L298 to control the SPEED of the motor. The direction of the motor needs to controlled from two more pins of the arduino.
Don't attempt this if you are on a tight schedule and not adept at arduino. Use off the shelf rc ESCs.

Please don't mind me saying this, but this is not the sort of project that can be spoon fed. You will have to play around with stuff and figure them out on your own.

If you could give the final requirement of the mission, may be it could make it easy for others to help you.

may we know the final intention of building the rover?

Oh I am sorry. Till now i didn't know that clarifying doubts is called spoon feeding. I am just asking the same question from the first post and i didn't get my answer yet.

if you are still stuck with your problem... use the following off the shelf...

http://robu.in/shop/sabertooth-dual-12a-motor-driver-for-r-c/

Sabertooth dual 12A motor driver for R/C

Dude...just PM me..i have build one for my friend..its pretty easy but a little confusing..
cheers :)