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Electronics => Electronics => Topic started by: dimebag94 on January 05, 2013, 04:23:38 PM

Title: Simple RC Quadcopter circuit
Post by: dimebag94 on January 05, 2013, 04:23:38 PM
Hello. I'm Antonio nice to meet you. For school purposes I'm projecting an simple RC Quadcopter using (almost) analog electronics. I split the receiver and transmitter circuits for clearance. Hope you have Eagle CAD because I attached my project in this post. It is really simple but I was wondering if it would work. Each circuit contains RF modules (not added yet) and coder/encoder. In the receiver there are 4 Mosfets driving 12V reversible DC brushed motors (I was also wondering which characteristics should they have like rpm or others) and they are paired up for CW and CCW rotation. The motors are driven by the decoder 4 outputs controlled by the encoder inputs. PWM1 is connected to SW1 and SW2 through diodes, SW1 drives CW motors and CW2 CCW motors. When PWM2 has  wider pulses than PWM1 and is connected to either CW or CW they should allow the quadcopter to yaw in either direction. SW 3 instead connects PWM to the rear CW motor and permits the quadcopter to go forward and as you can see motors 1 and 2 (batteries 1 and 2) are connected to PWM through diodes to avoid PWM pulses to go to the front rotor also. Thank you for reading and hope the schematic looks alright. Sorry for any mistakes. ;D
P.S. The 4th SW will be eventually used to activate the trigger of an dismounted electric airsoft gun.
Title: Re: Simple RC Quadcopter circuit
Post by: jwatte on January 06, 2013, 12:28:56 AM
If you haven't built a quadcopter yourself yet, I *highly* recommend basing your design on an existing kit.

Also, are you sure that brushed motors are the best option? Most quadcopters I've seen use "brushless outrunner" motors, which apparently weigh less and run faster. Also, the ESCs that control those motors are specifically designed for brushless motors.

It's unlikely that someone will download your entire kit, open it up in Eagle, and then start trying to debug it for you. That's a lot of work, and you're not making it easy for anyone to spend their time helping you for free.

Anyway, the best way to get involved is to just build it, and then figure out why it doesn't work. Unless you're starting with a proven kit, plan on the first one being entirely thrown away and replaced by the time you get to a working solution, so make sure you have at least 2x the budget of what your first kit costs.