Let's have a thread of random facts about anything:
I'll start; have you ever had your toolbox progressively start to smell like vomit and never smells better no matter how much you clean it? There's a reason for that. Namely, cellulose acetate butyrate handles like pic related.
The plastic breaks down over time releasing butyric acid, which smells like vomit.
Solution: wash with baking soda.
"It was a dark and stormy night" was first written by Edward Bulwer-Lytton who also coined the phrases "the pen is mightier than the sword" and "the almighty dollar'".
World peace could be achieved if only we work together.
The first ever in-game casualty in the Call of Duty series was a german soldier pissing on a tree.
The speed of light is invariant to all observers. Regardless of your reference frame, a beam of light will always be seen traveling the same rate relative to you.
For example, if you're traveling at 99% of the speed of light and you emit a photon, that photon will be 186,282 miles ahead of you in one second from your point of view. But a stationary bystander will see you and the photon a mere 1,862.82 miles apart from each other after that second has passed.
I might be drunk but this is making me feel really dumb.
physics is weird
Rubber bands last longer if they are refrigerated
The average IQ in the US is 98.
The average IQ of a black in the US is 85.
Since blacks make up 12.2 % of the US population, we can do some math:
Taking a representative sample of 1000, the total average would be 98. This makes for a cumulative IQ of 98,000.
Blacks, as a group, would make up 122 of this 1000 and they would have an average IQ of 85. This makes for a cumulative Black IQ of 10,370.
Now, we can subtract 122 from 1000 to get 878 non-black people.
Then we can subtract 10,370 from 98,000 to get a cumulative non-black IQ of 87,630.
Finally, we can divide the cumulative non-black IQ by the number of non-black people.
87,630/878=99.8
So, even if we removed all black people from the US, they would still be double-digit IQ retards.
Shit doesn't make sense, and the universe doesn't care.
How does europe compare?
Satellite television in the US operates on the C-Band at 3.7-4.2 GHz and 11.7-12.2GHz in Ku-band. The bandwidth is doubled by using the opposite polarity (horizontal and vertical signals, linear only). This means up to two GHz of bandwidth is available on a geosynchronous satellite.
(not to mention L, X and Ka bands)
Also from the perspective of a photon, zero time has passed between a photon being emitted and a photon colliding with an object. Even if it's billions of ly away.
I think this video talks about that
PID loop control is a process by which a system can be made to arrive at, and stabilize itself on, a point desired by the operator. This can be anything from the speed of a motor, to the temperature of a tank of water, to the position of a robotic arm. It does so by reading the current position of a system (called the process variable or PV for short), reading the desired potition (called the setpoint or SP for short), calculating the difference between the PV and SP (called error or E for short), then performing the PID calculation pictured in "PID.png" every scan cycle, this results in a final output (called the manipulated variable or MV for short) which then goes on to alter the position of the PV.
P GAIN
The P portion of the PID equation is your proportional control. This is the simplest one and some processes will use this alone as their control scheme. Simply put: the P value (set by the operator) is multiplied by E to get your proportional gain. In principle, this means the adjustment gets weaker as the PV approaches the SP leading to a smooth landing and instant stabilization. In practice, it means it will never fully overcome any force acting against it (like gravity, friction, wind, etc) when the error is sufficiently small.
A decent analogy is playing a game of tug of war against a significantly weaker opponent, but you have to use less force the closer the flag gets to dividing line. Once you get close enough to that line, your pull will be equal to your opponent's pull and the flag will stay right where it is. This results in an offset.
I GAIN
To correct this offset, I (integral) is used. What I does is it calculates a total sum of all errors, current and previous, then multiplies it by an I value set by the operator to get the integral gain. Sometimes a PI system is all that is needed for a control scheme. The result is a system which provides a stronger corrective force the longer the error persists. This has the problem of overshoot/undershoot. A PI system will have the tendency to make the PV fly right past the SP and then fall below the SP many times until the oscillation ceases. In fact, a hypothetical control scheme using only I will oscillate indefinitely as the overshoots and undershoots will always be equal to each other.
Back to the tug of war analogy, you now have the ability to use more force the longer the flag is away from the dividing line. This means that the flag will never be stuck anywhere but the dividing line. With a PI control scheme, you will be able to win your game with ease. This is where the analogy kinda breaks down, because you don't want to win, you want to get the flag to sit on the dividing line. A PI scheme in this situation would result in oscillation around the dividing line which dampens until eventually stabilizing.
D GAIN
In order to counter the oscillation resulting from PI control, D (derivative) is required. D subtracts the current error from the error immediately previous to it then multiplies the difference by a D value set by the operator. This results in a sort of counter corrective gain which effectively weakens the system's ability to respond quickly to a change in the PV. Essentially, the faster the PV is changing, the more D is going to attempt to resist that change. In conjunction with PI, the oscillation will be halted sooner with a higher D value at the cost of slower response time. A PD control scheme is somewhat rare, but they do exist in applications where overshoot is of great concern and there is little risk of an offset forming. Such a scheme will have the PV slowly approach the SP and would be unlikely to ever overshoot, but without the I correction there is no protection against the aforementioned offset.
cont.
PID
A PID scheme is one which utilizes all 3 of these parameters in order to allow the PV to approach the SP in a manner suitable for the application. Some tuning methods, such as "Ziegler Nichols," will respond quickly and aggressively to get the PV stabilized on the SP in as short an amount of time as possible. Other methods, like "no overshoot" will respond very slowly and weakly to get the PV stabilized on the SP with as gracefully as possible. And then you have everything in between.
SUMMARY
I know this was a really long post, so I'll tie a bow on it here:
there's an island in Maryland where horses roam free. it's forbidden to go within 10 feet of them, so they can ruin your whole day if they feel like being jerks.
So realistically where and how is this used and what does the calculations? Some sort of a microcontroller?
Quad copters and segways are the most commonly cited examples. Cruise control in a car uses it. Guided missles. Basically anything requiring:
Generally, yes. You can also do it analogue with op-amps, resistors, and capacitors but that has some caveats and basically went out of style with the popularization of the microcontroller.
any parameter control (pressure, flow, level, temperature,….etc) retard
in case you're curious:
those three op amps (triangles) arranged in a column in the middle of the schematic are, from top to bottom:
R12 is a potentiometer. Basically a knob that you can turn to vary the resistance. You divide the resistance of R12 by the resistance of R6 (which is not a knob) to get the gain from the op-amp which is your multiplier for the current applied to it.
the capacitor (C1) has a lower resistance the faster the the change in current is. So applying the same rule from the P op-amp, you divide the value of the potentiometer (R13) by the resistance of C1 to get your derivative gain. The faster the change in current, the lower the divisor is, the higher the gain is.
This time, the capacitor (C2) is your feedback. Wired in this way, it acts essentially as a storage device. The more voltage it stores, the higher its resistance. For I, the potentiometer (R14) is the divisor, meaning that the higher you set it, the lower the gain is going to be. This is a quirk in the way analogue PID works because of the way the potentiometer has to be wired for the circuit to work.
0lzod0Ae1Tlk k00zEhW48WVB
Must suck to have to be always comparing yourself to America since deep down you know its the best country in the world.
Poop smells like Poop
it includes anyone who isn't black.
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The average Woman over a lifetime get about 53.18 linear miles of dick sliding into her pussy. Thats also 53.18 linear miles of dick sliding out of her pussy. That means that the average labia gets rubbed with over 100 linear miles of dick in a lifetime. Most women get way less and some get way way way more.
Niggers have a darker skin colour than Caucasian people, and also a lower IQ.
It used to be a well known method to use small yet very sharp knives to erase stuff written by pens.
This was one of the intended purposes why some Swiss army knives have a smaller blade alongside the main bigger one.
Put some toilet paper in the toilet before you shit in it. It prevents water from splashing your ass and probably makes shitting a million times more hygienic as a result.
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Castoreum is produced in the castor sacs in a beaver's asshole.
This substance has a sweet taste and smell, lending itself to be used as "natural flavoring" in vanilla, raspberry, strawberry, and other flavored drinks.
You will seldom find this listed on any ingredients label. It is simply one of the many things that can be placed under the umbrella term of "natural flavors."
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That's gotta piss off some Mudslimes, love it.
Fuck off back to >>>Holla Forums with the other fedoras.
HAHAHA, retard.
is the baby cells meme real?
like, i know christianfags keep shilling it, but is it real?
that's worldwide, dipshit.
I don't know, but the thing explaining what exactly Senonymx does is at the very least equally scary. And that does seem to be rather factual.
Most people have more than the average number of legs.
took me a while to get it. 7/10
Stands to reason. Even one person with fewer than two legs drops the average to >2 legs.
but then even one person with more than two legs rises it back up
What's the reason for this? Seems like a rather stupid rule. Those horses are clearly used to human contact meaning they'll just about roam wherever the hell they can.
might be the county or whoever's in charge of the place wanting to avoid lawsuits from people who got bitten or kicked
But human civilization strives on struggle. We need to struggle against another enemy to advance.
Ozymandias pls
random user with no good reply pls
Or you know, just put a hole in the ground like us Europeans.>>7251228
yo yo yo