A quadcopter w/o gyro, LiPo, and uses fake NRF24L01 PA LNA--is it possible?

Hello

I’m really new to the forum, so please let me know if I’m like not following any forum rules, if there are any

I just wanted to know if I can get this planned quadcopter fly. At first, I planned to by LiPos but they couldn’t ship to where I live (Guam). So I planned on using a powerbank, connecting it to my (fake) Arduino Nano via USB, and using the 5v to provide power to my motors. As for the receiver and remote control, I’ll be using NRF24L01+PA+LNA from either eBay or Banggood (pretty sure they’re fakes) and some Nanos.

And I’m too cheap to buy a gyro

So my questions are:

  1. is it possible?
  2. do the fake NRFs work like the genuines (in terms of range)
  3. can I use 5v to power a 30a 2450kv brushless motor (I’ll be using ESCs, which I assume help provide th high current?)

I’m willing to spend on LiPo batteries, but the prob is the price and the shipping area.

Also, I’m afraid those NRFs won’t work like the genuines or if there will be an information dump like in the real Nordic ones.

Basically, the goal here was to build a quad under about $80. It’s for my robotics project.

Thanks in advance,

Jerome

I have never had a quadcopter (or even a monocopter) but I suspect the MOST IMPORTANT item is the gyro.

If the gyro enables the 'copter to remain stable for a short period of time the communication system becomes a lot less critical. And also your reaction times.

Of course you also need an appropriate thrust to weight ratio - but that is not really an Arduino issue.

…R

Can't I just manually control the quad using my controller?
Like if it is unstable and, for some reason rolling left, I just roll right?
Thanks, though

JeromeAriola:
Can't I just manually control the quad using my controller?
Like if it is unstable and, for some reason rolling left, I just roll right?
Thanks, though

You would have to be able to coordinate precisely controlling four motors manually to keep it steady.
The gyro is the most important peice of the equation, a mpu-6050 should be dirt cheap on eBay.

I build quads for about 50 dollars or so ( not including transmitter) with my own home built esc's and flight controller. Definitely a doable and rewarding project.

Some people have used the 18650 batteries like from a battery bank but the aren't made for a high current draw, the may work for a very efficient quad and mild flying.

I have never had a problem with nrf24 radios from all different sources, the chip is soo cheap I don't know if there are really that many fakes out there.

You will need a seperate 3.3V supply for the high power NRF, the Nano can not deliver the needed current.

5 volts from the batter bank is not going to cut it either, if you want to use those cells you will have to remove them and not use their regulator.

Edit: for powering the motors..

Ok this is really giving me new ideas.
Thanks, alka. I haven't really been looking for gyros, but that mpu6050 is hella cheap ( less than $2 on ebay)
And where can I get a 3.3v power supply?

You could use something like this Mini360-DC-DC-Buck-Converter-Step-Down-Module € 0,38.

All kinds of options, a linear regulator isn't bad either just to bring down 5v to 3.3. lm1117 is pretty cheap.

A linear regulator is very inefficient compared to a switching regulator.
I would not use them for battery powered objects unless I need the heat for something.

Whandall:
A linear regulator is very inefficient compared to a switching regulator.
I would not use them for battery powered objects unless I need the heat for something.

Linear regulators and switching regulators both have their uses. Dropping a small voltage to deliver a small current for sensitive devices is what linear regulators are actually good at.
There is no one better than the other, they both have strengths in different applications.

In my code, I was planning on doing something like I'll make the arduino move the front and back left motors if I did the command on my controller for right roll. Wouldn't that suffice for "controllability?"

Although I do wanna buy a gyro...

So basically I wire the gyro onto my nano and it'll do its magic?

I think manual control of small quadrotors is beyond most humans capabilities. I would love to be proven wrong.. I think it would be just too hard to co-ordinate. With years of dedication and practice you may be able to hover.
Two of the props need to be spinning clockwise and two counter clockwise, you would have to coordinate that too in order to not spin out of control.

You would have to write code to make the mpu6050 do it's magic. Or look into multiwii, the mpu6050 is supported.

alka:
Linear regulators and switching regulators both have their uses. Dropping a small voltage to deliver a small current for sensitive devices is what linear regulators are actually good at.

Both will not be the case for a quad, 3.3V ist probably way below the motor voltage and the current demand of high-power-NRFs is not small.

Whandall:
and the current demand of high-power-NRFs is not small.

I thought one would use a low power nRF24 on the 'copter to save weight

Compared to the energy being used in the motors the losses in an LM1117 would surely be trivial. The SOIC version of the LM1117 is small and light, but not too small for hand soldering.

…R

Robin2:
I thought one would use a low power nRF24 on the 'copter to save weight

Then there would no reason for a high power module at all,
unless you only want unidirectional communication (no acknowledges).

Robin2:
Compared to the energy being used in the motors the losses in an LM1117 would surely be trivial.
The SOIC version of the LM1117 is small and light, but not too small for hand soldering.

Wasting energy by converting it to heat is not the best strategy to get maximum flight time.

The linear solution has less weight, admitted.
But - to follow your line of argument - compared to the weight of the motors it is rather small. :wink:

Whandall:
Then there would no reason for a high power module at all,
unless you only want unidirectional communication (no acknowledges).

I have no experience of the high-power nRF24s with the external antenna. As well as being high-power for transmitting I had also assumed they would be better at receiving - is that wrong?

Wasting energy by converting it to heat is not the best strategy to get maximum flight time.

The linear solution has less weight, admitted.
But - to follow your line of argument - compared to the weight of the motors it is rather small. :wink:

I suspect the weight saving would have a bigger improvement in flight time by reducing the energy needed by the lift motors than the extra energy wasted by the less efficient conversion.

...R

After i acquire all my resources (motors, escs, gyro, etc) will my nano have enough pins to support all that (in terms of space and wouldn’t it like overload?)

You should have enough pins.
4 PWM for motors,
5 SPI for radio
2 i2c pins for gyro
Lots left over.

If the PA nrf24 version draws 100ma steady then you would be burning a whopping 0.17 watts of power! Dropping from 5v. I doubt it needs 100ma continuous too.

Because of the low RF noise of a linear regulator I would choose it in this application ( radio communication).

The gyro is another case of a device extremely sensitive to noise, a linear regulator is much preferred over a switching regulator. The breakout for the mpu6050 will also have a little linear regulator on it.

Use the right tool for the job, it’s like saying a truck is better than a car.

alka:
If the PA nrf24 version draws 100ma steady then you would be burning a whopping 0.17 watts of power! Dropping from 5v. I doubt it needs 100ma continuous too.

The motors are probably using 100 times as much (or more). This is not a project to make an AA cell last for 6 months !

...R