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4

I would not use this arrangement, except in some rare scenarios. The lipo batteries are a very low impedance voltage source, so if you use good routing, and decoupling you shouldn't need any filter. Route the power from as near the battery as possible. You don't want to share wires that are supplying current to the motors if possible. Add a large ...


3

How important are these last five digits and how risky is it to install a part whose last digits are different? The last 5 digits are important because they tell you the number of turns and diameter of wire on the armature, which determines the motor's power and torque. Too few turns will draw too much current, which will reduce the motor's lifespan and ...


3

Firstly, you're not going to get the motor to do much as it's configured at the moment. There are places on the terminal block for an external power supply, that will by default also power the Arduino through the Vin pin in the header - which is connected to the power jack on the Arduino board - there's a Vin cut-to-disconnect pad on the underside of the ...


3

In many of these old-school devices the motor speed was controlled by a centrifugal governor on the rotor of the motor, so faster was not an option only slower. I built this: it worked well enough to be a fun toy: simulate this circuit – Schematic created using CircuitLab it just plugged into the 'Cue' socket (J4 REM on your schematic) placing it ...


3

If I needed to filter the power supply to the nano, I would use a ferrite bead instead of the resistor. The thing about linear regulators, such as that in the Arduino Nano, is that they don't react fast enough (have a high enough bandwidth) at higher frequencies so they can't filter out high frequency noise from things that switch (like motor drivers). They ...


2

Is this motor self starting? If yes, then how? The motor is electronically controlled, so it doesn't need to be self starting in the usual sense. The controller energizes the stator at a low frequency. That creates a slowly rotating magnetic field that the rotor is able to follow. You can think of the motor as initially operating as a stepper motor. As the ...


2

Lose the resistor. You can add extra bypass caps if you have problems, although they may or may not be necessary. In addition to the suggestions in other answers, a quick and dirty fix for high frequency/motor noise getting passed through a linear regulator is to simply use a separate battery (for instance a small 1S lipo) to power your sensitive control ...


1

All of the points mentioned will limit getting more power from the motor than it is designed for. Motors that are well designed are usually close to the design limits in all of the aspects mentioned. The most likely avenue for getting more power from a given stator and rotor would be to rewind the motor for a higher voltage and a higher speed, but it ...


1

The poles of a coil are at the open ends of the coil (look at the way the magnetic fields generated around the wire combine to produce an overall magnetic field for the coil), and you want the ends of the poles on the stator and rotor to face each other.


1

To clarify what comments are evoking and answer your questions : The battery A true 20Ah battery will be able to provide 20A during 1h, 40A during 30min or 10A during 2h. Ok that's obvious. You must be aware of the capacity derating that occurs on high discharge currents so you won't be able to get the full capacity. Moreover some Chinese accus capacity are ...


1

There can be several good choices. As of now I think the selection you have done fair enough and should work. The new chosen diode had maximum Reverse voltage of 50 V Rating and it should be okay for a DC motor. If you have a chance, you can choose a diode with higher reverse Vorlage Rating. The \$V_{GS}\$ of chosen new MOSFET is even better than the ...


1

The motor controller in your drone doesn't use resistance to control motor RPM. Instead, it uses a PWM chop to vary the duty cycle and thus the delivered power. Duty cycle has roughly a linear relationship to power delivered to the load, which will have some not-linear relationship to RPM. An inexpensive bench supply with variable voltage and current is a ...


1

As I commented on the question, you're probably better off with conventional relays given that: their cost scales better as you go for larger/more powerful motors they are less complicated (since you stated that you've never designed a circuit before) Having said that, if you wish to pursue the solid state approach then you're probably aiming at (MOS)FETs ...


1

You neglect friction. If you also neglect air resistance, and have an infinitely long, straight coil, and the battery has an infinite charge so it will never run empty, then, I'd guess, the train will reach eventually the speed of light. Eventually meaning after an infinite amount of time.


1

this should be -1 in both cases, because it refers to a negative feedback being unitary TF_DC_vel_closed = feedback(TF_DC_vel, -1) The \$ T \$ means the sampling period, so, every \$ T\$ seconds the system gets new sensor measurements and updates its output \$u(t)\$. Also, notice that you have not used at all gho. I would suggest discretizing \$G_{p1}\$...


1

The wiring is sort of described in the limited manual for the motor shield. https://docs.rs-online.com/cafb/0900766b816c20f3.pdf Or in this instructable: https://www.instructables.com/id/Arduino-Motor-Shield-Tutorial/ Two of the top most results from a google search on arduino motor sheild. And read up on PWM (in either the datasheet for the avr-controller ...


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