Will still work with a more powerful motor?

So I have this project(RC Multipurpose planter with solar panel) for my final year in mechanical engineering, and have been researching on electronic schematic diagrams. I don't have much knowledge on making circuit diagrams so i searched for one.


And this is what i have found, a simple and small diy remote controlled robot schematic diagrams. (See site and pics)
(Credits to the publisher)

https://diyhacking.com/remote-control-car/


Transmitter Circuit:

Receiver Circuit:


It is relatively simple and easy to build. I think this is gonna work for my project.

However...
I'm gonna need a larger dc motor since the weight of my robot is about 30kg (about two 40W power of a 12VDC motor)(Moving at 2km/hr)
And im gonna add a solar panel for recharge-ability and sustain.

My questions are:
1. Will this still work and not fry up even if i use a larger motor? (Since ill have a larger motor, ill have a higher amperage for a constant 12V DC motor)
2. How do i configure this circuit to meet my required power to drive my 30kg robot.
3. How and where do i install my solar panel?
4. Any recommendations?


 

The LM393D cannot drive more than about 500mA continuously. At 12V, your 40W motors will be drawing at least 3.3A (3300mA).

There are a wide variety of DC brushed motor drivers that can handle this current, this one: http://www.robotshop.com/en/10a-dc-motor-driv...zdOvaHhTql40fhMf8O-DIlMXTseKg9hX78aAkSC8P8HAQ will drive a single motor. Google "DC brushed motor driver" to find additional possibilities.

Solar recharge is going to be ineffective unless you are only going to operate the robot a very small percentage of the time. A 20W medium efficiency solar panel is close to 0.5 m^2 which I suspect is going to be much too large for your robot.