This project is a quadcopter called raven. actually this project hasn’t done yet though.
I’ve started it few weeks ago and I stoped that becasuse of my final tests at IKIU.
Let me start from the begining.
I’ve got an idea to make a quadcopter with dc motor driver(I’d already done enough projects with ESP8266 NodeMCU module) so I searched around dc driver motors,
there was L298 driver (which it wasn’t appropriate for a quadcopter because it’s old, large and it uses old non-smd MOSFET which makes it hot after a while), L9110S driver(which I bought at first time), TB6612FNG driver(too expensive) etc.
I didn’t have any exprience about coreless motors and how much current they need so I bought two L9110S.
The L9110S driver is a two-channel, H-bridge DC motor driver and each channel maximum current is 800mA! and I’ve said before, I didn’t know a coreless motor in it’s maximum speed with a reasonable propeller may needs 1.8A so L9110S was a bad mistake. Altought I knew it’s not gonna work but I assembled it just for fun to see what happen and the result was this
This quadcopter(it’s not even close to be a quadcopter) had several issues :
1.it was too heavy, two L9110S driver with a NodeMCU module and the battery(a Pod Vape Li-ion 600mA 8A battery) which was heaviest item.
2.fake battery, a quadcopter needs Li-pol battery which is light and also it needs a battery with high discharge coefficient.
3.inappropriate motor driver
4.bad wiring, the picture above clearly shows that the wiring is a mess. 5.weak motors, I’ve got four 720 coreless motors which was obviously too weak but I hadn’t realize that.
So I’ve researched to find a better motor driver and after lots of searching and scrolling I found DRV8833 motor driver, it gave me a lot of hope.
The DRV8833 driver basically works like L9110S(much smaller than L9110S and also with AT8833 IC) but with a important difference, the DRV8833 provides 2A peak per channel and provides 1.2A continuously per channel. Therefore, I bought two of them.
To solve the battery issue I bought a Li-pol 600mA 25C quadcopter battery which it was so light.
I wasn’t going to believe the fact that my coreless motors are weak and it should be the first thing to replace and I assembled the quadcopter again and this time motors were working at highest speed(because I’d set PWM duty cycle to 100%) but still the quadcopter couldn’t fly and after a while working in maximum speed, the flying wasn’t the main problem the drivers were.
Yes, the drivers were close be burnt and in that moment I realized an appropriate driver must provide at least 1A more than the current each motor needs to work in maximum speed.
But this time there wasn’t the driver I need so I had to make my own DC motor driver.
I knew first thing that a motor driver needs is a MOSFET but I didn’t know other stuff a driver needs.
So I’ve searched alot and I finally realized what a motor driver needs(in this case I didn’t need H-brigde) :
1.High current SMD MOSFET
2.Pull down Resistor, to discharge the MOSFET gate.
3.SMD Diode, as a flyback diode.
So, I designed this scheme
And after buying AO3400 MOSFET SOT23 package, M7 Diode and 10K Resistor I made four of this :
The only problem right now is the motors and I’m gonna buy 8520 Coreless after my final tests.
If the quadcopter flies, it gonna need Accelerometer/Gyroscope sensor like MPU6050 or MPU9250.
