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5

I must agree with the other two answers, however the main issue is that you do not have enough voltage into your regulator (I see from your comment to Ian that you are using a Pololu D15V35F5S3 Regulator). If you refer to the Pololu D15V35F5S3 Product Description, down at the bottom you will find the following graph: Looking at the red line for 5V output: ...


5

It sounds like you're experiencing a "brown out" caused when the excessive current draw from the battery causes a drop in the supply voltage. This is due to the fact that batteries have internal resistance (a.k.a output impedance). In this example, if the load drops to $0.2\Omega$, the internal resistance of the battery will cause the output voltage to be ...


5

Since you're running directly from a battery I would say it's safe to just add as much decoupling (in other words caps across your input power) as possible, since the only real downside (that I think is relevant to your setup) to adding a lot of capacitance is increased in-rush current (since the capacitor naturally acts as a short-circuit during charge-up). ...


5

The servo.write(angle) function is designed to accept angles from 0 to 180. (The value 180 is significantly larger than 100). Could you tell me where in the Servo documentation you read "100 (motor at full power)", so we can fix that typo? Please change the line int maxspeed=100; /* wrong */ to int maxspeed=180; Also, please run servo.refresh() ...


4

Your code uses the typical servo.attach(pin) where you can use the overload of servo.attach(pin, min, max) to set the min and max microseconds of the pulse width to match the desired ranges for you ESC. Additionally to make it a bit more clear where myservo.write(90); is used to set the angle, you can use myservo.writeMicroseconds(1500); to set the duration ...


4

You're asking about microcontrollers, but I get the sense that you're asking it for the wrong reasons. Since you don't list a technical reason for being "not a fan of arduino", I get the sense that you're trying to make a quadcopter that is different in every way from existing solution. This decision sounds at best arbitrary and at worst misguided. Why ...


3

Okay I thought I'd move this to an answer because I think this will help clear up some confusion you have. First, if you are trying to plot RPM vs Thrust, then your battery, ESC, power, etc. have nothing to do with RPM vs Thrust, assuming the battery and ESC are sized correctly to provide adequate current to the motor. It's like saying you want to ...


3

You can't understand this because you don't know what you observe. The electromotive force (EMF) of your motor is proportional to its speed (the ratio is called Kv). So, when the speed of your motor rises, the EMF rises too. What does an ESC ? Basically, it hashes the input voltage to generate the expected output voltage. So, what is this decreasing ...


3

Yes, as this motor is rated for 100amps stall at 12V you should probably be using a motor controller capable of supplying that amount of current. Regarding how to drive the motor, the following may be of use: A voltage regulator cannot be used to drive a motor. What it does is convert a certain voltage to another voltage, for example 5v to 12v. It does ...


3

Ideally, when you raise the collective all the way up, all the ESCs put out their max power and the quadcopter goes straight up. Different ESCs will end up producing different maximum thrusts; and also will ramp up (and down) differently with sudden changes in control signal. As you probably already know, if one rotor of a multirotor vehicle has more (or ...


3

In process of selection of components for multirotor, one should start from motor as it is the driving component. Maximum current drawn by your motor is given by manufacture which is 15A. Now your ESC should have maximum current rating more than maximum current rating of motor. This is satisfied in your motor-ESC combination so your selection looks good. ...


3

First, you can look at Mikrokopter as an example of quad with centrally mounted ESCs. As for the various engineering reasons for ESC location, here is some rationale behind the two you mentioned 1) Interference/noise. Non-steady state current running through wire can induce current to flow in nearby conductors. Practically speaking, this means that if you ...


3

Your equipment will be fine as long as the stall periods aren't too big(like 5 minutes). I think the first thing to fail is the ESC as you're using half the voltage the motor is rated for. You also have to take into account that the battery can also heat up and fail, as if you would short circuit the battery. But as I said, if it's not for long periods of ...


3

Well over voltage at an ESC usually results in an instant magic smoke. I would never recommend this. If you have enough reserve power you can use the 3S version. If you are not sure or do not have enough power reserve then you should buy 4s ESCs.


3

I believe there is confusion about these terms. Strictly speaking, the ESC is PWM controlled. Although the signal usually gets there from a transmitter and receiver signal that is PPM encoded. It seems to me, that many sources will have you believe that PPM is just a multiplexed PWM like this: But in reality it is actually more like this: Note in the ...


3

What is the problem you're having? You ask, "Can anybody figure out what I'm doing wrong?" but you don't state clearly what your problem is. Will the motors not spin up after? Is anything happening when you do the calibration? As an FYI, here is an answer on EE stack exchange explaining the basic startup modes for an electronic speed controller. Quoting: ...


3

It depends on the voltage. Say you are running 12V: 1820W / 12V = 151A With a 24V system: 1820W / 24 = 75A


2

Typically you want to power the ESCs directly from the battery, and use a BEC to power 5v electronics such as your controller. However, a lot of ESCs have the ability to provide 5v power back to the controller over the 5v line on their control cable (servo-style 3 pin cable). In that case, you wouldn't need to use a BEC at all, but it's possible you might ...


2

For each motor the output should be: A value at which the power from the 4 motors roughly keeps the quadcopter airborne, for instance 1500ms. Plus or minus the influence of the throttle. For instance with your throttle is in the 0:1 range you could apply 600 * (throttle - 0.5), which will put the motors output in the 1200:1800ms range. Plus or minus the ...


2

An Electronic Speed Controller can be used in various situations, and rather than make 20 different speed controllers for every different situation, they make one which is programmable. The options you have vary depending on the ESC you buy, but typical ones include: Battery types (NiMh, LiPo) Different battery voltages Cut-off voltages Whether or not it ...


2

First a little warning: This answer is one big AFAIK. I have some limited experience with RC electronics and don't know anything about industrial servos, and other simillar stuff :-) BLDC motors (just motors) don't have any kind of RPM feedback, they are just three sets of coils and a bunch of magnets. The electronics that drives them can do some magic, ...


2

I use those RCtimer ESCs and they have always worked great for me, generally thease (and most) ESCs will be looking for 50Hz pwm with a period between 1-2ms, though generally you will not damage them by altering the pwm output. I would recommended cutting the 5v supply on each ESC as they can act funny and even damage themselves when they are all tied to ...


2

Motors stalling can take many amps as you have found out. In the electrical industry three types of overload cut out are available. fuse, trip, auto resetting trip. A more suttle way is to monitor the motor amps and if an overload happens limit out the power to the motor. For example current limitors If the motor windings have them (very rear) thermistors ...


2

What exactly is the question? I'm not sure, so I'll describe one system I have, and hope you find your answer somewhere in this description. I connect my Arduino USB cable to my laptop all the time, both before and after applying main motor power. power "How do I start the Arduino before inserting the USB cable?" Many people find it easier to plug a AC-...


2

I'm not an expert re: PPM communications but, from what I can tell, PPM signals contain pulses which are interpreted by the receiving microprocessor (or speed controller) as position commands. If the pulse is the smallest acceptable width, then the position of the servo will be commanded to go completely to one side; if the pulse is the largest acceptable ...


2

First of all I would suggest calibrating them. From the eBay page you linked to, It would seem that the ESCs are probably HobbyWing (or HobbyWing clones). I would suggest finding some spec sheets for HobbyWing ESCs and using that information to calibrate them as well as understand them better. Since they seem to respond to values in the range 800-1800 ...


2

Can you make a written description (comments, text, or block diagram) of what you think the code is supposed to be doing? I can't figure out what your whole timer scheme is supposed to do. Here's what happens when you execute it, though (assuming you make it to the main loop okay): void loop() { So here you start a loop. By definition, it loops. while (...


1

First thing first: you can't observe your rotor's location at 0 speed, because at 0 speed, you've got no back EMF. You must make your motor ramp to a speed that allows you to observe it electronically. This is done open-loop. To perform your ramp, you need to generate a voltage slightly above the BEMF at the ramping speed. Slightly above means that you ...


1

It doesn't seem like those motors are well matched to your battery. They recommend a 2or3 cell LiPo (7.2V or 11.1V) while you are using a 1 cell LiPo (3.6V). I think you'll find most motors will recommend 2 or 3 cells. With only 1 cell you won't likely get enough lift for a multirotor. Also as a side note, your ESCs should be set to have no cut-off when ...


1

Operating an ESC is practically the same as operating a servo. The main difference is that instead of the pulse width translating to a position on the servo, it translates to an output speed. The range of widths is identical with ~1000µs representing the lowest setting and ~2000µs representing full on. These values can sometimes go beyond (as overshoot), ...


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