Control Definition and 1000 Threads

Why is it that forces (for changes in pressure across a fluid) on the control volume are generally considered compressive? Even in the derivation of the Navier-Stokes equation, it is assumed that forces from fluid pressure will be compressive? Why?

Hi guys, currently i am stuck with the limit switches in the sequential control circuit. the Normally open,heldclosed, Normally closed,held open , normally closed and normnally open. Let's say if bo is NO,HC. so the switch will be normally open then once bo is actuated then the switch will...

How do control rods get in there!? This is a bit annoying for me, hopefully someone can help. You have fuel pellets in rods. They are en capsuled by cladding to make sure fission fragments cannot escape into the moderator. Do the fission neutrons pass through this cladding into the open...

Homework Statement Attached below. Homework Equations How can I know I got the correct set of parameter in step 5. I did everything using MATLAB but couldn't figure out how to get the right value of the zero. The Attempt at a Solution Attached below.

A "DIY" Electronic Speed Control ? is that viable? The concept of 3-stage brushless motors does seem very simple to me. Simply power the 3 different stages at different times, use 2 at the same time and the 3rd as a magnetic sensor. When the sensor goes on you flip the stages, one goes off and...

1. I have to use Simulink to check the step response of a state feed-back design (controller) and state estimator (observer). I did the problem and got matrices that I need for the desired poles but I'm not sure how to use Simulink to do them.3. I really don't want to post the exact vales to my...

I am a math grad student who has really got interested in spacecraft control and navigation. Like a lot of people, I have been playing too much ksp and gotten interested in the mathematics of spacecraft navigation and control. For fun, I derived some basic motion and control equations...

Can anyone recommend a company that provide advanced control systems for marine and civil engineering in the Cambridgeshire area? Thank you

In this experiment, we'd learn about vector control of an induction motor. By using the constant rotor flux linkage vector control method, An AC induction motor can achieve a DC motor-like performance. Firstly, we tested on speed control response in steady state. *the proportional gain kp =...

This is a revision question rather than homework as I have the answer and working. I have attached the block diagram and first part of the answer which explains how to derive the transfer function from first principles. I understand the principles behind this and how the RHS of the equation...

The radical Smolin thread left me wondering if other similar ideas could not be applied to other areas of Cosmology and even Particle Physics. Every complex system I can think of in our lives, and in nature, forms part of a complex multifaceted control system or process, with various feedback...

Hello, I was reading somewhere about how to control Rudders in RC planes. The basic equation here is the drag equation: F=0.5*ρ*v^2*C*A (take ρ=1Kg/m3) where v is the velocity, C is the Drag coefficient of the control surface (Rudder in this case) and A is the area. I am wondering if we have...

Hi. I am writing a report on an experiment. The experiment is on power electronics. An investigation of V /f constant control of induction motor with inverter was carried out. A converter and an inverter are connected to an induction motor to change AC to DC and back to AC, as shown in the...

Hello. I have to do an experiment on this topic, but there are many things I don't know. First of all, can you tell me what do the symbols V~ and A~ mean?

Been reading some Dover books (topology, ODE:s, complex variables) and I think they've been just brilliant so far. I'd like more books in the same vein on other subjects. Most engineering books are absolutely awful in my opinion (books in the style of Merriam/Kraige mechanics - utterly...

Hello I asked a question about infrared and UV a while back for which I got some very informative responses: https://www.physicsforums.com/showthread.php?t=676881 This is in a sense a very short follow up question: Is the reason that we don't feel 'heat' from an infrared remote...

A company called ClearSign says it can use electric fields to shape combustion flames to improve powerplant efficiency by upto 30%: http://www.technologyreview.com/news/520466/flame-shaping-electric-fields-could-make-power-plants-cleaner/...

What represent reactivity excess and how is it determined How we can evaluate control rods worth by measurements and by using computer code. It is absolout necessary to take into consideration control rods interfering efect? All problems regarding research reactor. Also if exist some books...

how can we control stepper motor in emu8086? we have to take input AT RUNTIME that if we enter 0 it will stop the stepper motor, 1 for slow speed, 2 for medium and 3 for fast speed.

Dear all, This is a newbie asking for some information. Actually, we have 1x30HP, 2x10HP motors working at our workplace. When we start the motors there is a lot of torque generated due to which our grid supply charges us penalty every month. We need information about the device(s) that...

Hello, I'm working on obtaining an equation that will help me model the behavior of velocity as a response to the current flowing to a coil in a MagLev. I have tried to relate momentum and electromagnetic momentum: m*v=F*Δt F=q(E+ v X B) V= (q(E+ v X B) Δt)/m Am I going the right...

I'm wondering if anybody can list some schools that offer a Masters in Controls Engineering. Preferably without a thesis and 100% online. Also, how would a Masters of Electrical Engineering (MSEE, M.eng) compare to a more specific degree (such as controls, mechatronics, etc.)?

Homework Statement http://i988.photobucket.com/albums/af10/postop/equationsmomentum_zpse8c8d44a.png Homework Equations The Attempt at a Solution Can somebody explain to me in the two equations above what is the "u" and what is the "v"? In the question, it says that the water at...

Homework Statement Since this is a third order system and there will be a zero in its transfer function i am confused that how the natural frequency and K will be linked ? Please do help i really get confused in these type of problems. Homework Equations The Attempt at a Solution...

Evo don't you dare close this thread I want at least one answer as to why it can or can't work :P So sinse we can strap electrodes to our heads and with nothing but thought, we can make something happen, whether it's moving a rats tail, moving a ball bearing or making someone elses finger...

Homework Statement The angular velocity of a process control motor is (21−(1/2t^2)) rad/s, where t is in seconds. 1.) At what time does the motor reverse direction? 2.) Through what angle does the motor turn between t =0 s and the instant at which it reverses direction? Homework Equations...

I am in the middle of designing a low drift and low ripple power supply for myself. To control the output voltage, which ranges from 0 to 20V, I am using an op amp whose output is fed into a Darlington pair of power bjts. The output of the Darlington pair is both fed back to the op amp's...

Hello, My professor did a lecture about mass conservation in a system. He basically explained the lining that separates the system from the surroundings is the control surface, and all that is contained within the system is the control volume. I think it was explained rather loosely, and...

Hello, I'm a mechanical engineering major/electrical engineering minor university student. A huge part of mechanical and electrical engineering is control theory, which I enjoy immensly. I have yet to take any ME control electives but took a systems/stability course as my last EE elective...

I'm having problem with task (a) in this problem The question My attempt The solution Why don't I get the same after I take the partial fraction using my calculator? And where does this R(s)=1/s^2 come from

Dear all, I am building an arm with 2 joints(elbow, shoulder) and want to optimally control it to a particular position(wirst). The examples I saw so far(e.g. acrobot) have a target control signal u(t_f) which becomes zero when reaching the target x_{target} in the final time step t_f. In my...

Hi all. I'm trying to come up with a way to determine if the defectivity of a particular widget is 'different' to the usual defectivity of a widget. The difficulty comes from the fact that widgets are made in batches of 25. We'd like to investigate any widgets which have a higher (or lower)...

Hi all, I am wondering if time has any control over light or is it vice versa? For instance, is light speed controlled by time? I have read that it is impossible for anything to travel faster than light and time slows down the closer you get to light speed. Is this because of time being in...

In dc motors, speed can be increased by weakening or decreasing the field flux. The mathematical explanation is --- Speed is inversely proportional to flux. But why is it so? Should not it be that when flux decreases torque decreases which is driving the motor. Now decrease in Torque should...

Hi all, I am a student and I am trying to understand how to achieve carrier phase stabilization for frequency comb using quantum interference. I found out that the interference leads to generation of current but I can't seem to find the derivation of the equations for the current generation...

Could someone refer a book or a tutorial that explains the concept of "control structure" - In section 3 of the following paper http://link.springer.com/article/10.1007/BF01797154# in simpler terms? Thanks in advance Evrin

I came up with this question while studying for an upcoming exam. I had a design problem, my solution gave me a gain of about 5500 with a PI compensator. Does having that high of a gain screw with my system? It gives me the desired results in MATLAB, but are there any drawbacks to doing that?

Hello folks, I am having hard time to decide which class to take in my senior year. I have two choices: Embedded Systems with primary focus on FPGA and VHDL and another class is Control Systems design. I like both of them, but the problem is that they are offered almost at the same time, so I...

How exactly would you describe the principle of a valve for flow control? In a globe valve for example the fluid flows through valve seat and generally leaves the valve with the outlet diameter being the same as the inlet diameter. My original assumptions were that Bernoulli's principle...

Heyo, Finally taking my first senior level course in Mechanical Engineering - Dynamic Systems and Controls. I find it incredibly interesting and was hoping someone could suggest an easy to medium difficulty project I could do on my own. This is for my own edification. The book that my class...

I was reading through an article on, "Shunt Reactors for Voltage Control" and I am slightly confused. (See link below for article) http://www.onegrid.com.au/wp-content/uploads/2012/03/BR-EN-TH16-02_2006-Shunt_reactors_for_voltage_control.pdf The article reads, "When the network load and...

I just watched a video by Koenigsegg engineers and came across this question. Why is camshaft the primary control of the engine valves? Using electronic controlled actuators would certainly benefit the engine in aspect of performance, but might increase the cost of production as well. People...

So I want to build an electric longboard. I have access to pretty much any machining equipment but don't have much knowledge on the electrical side of things. I know I will need a LiPo battery (I am aware of the dangers of them), and an electronic speed controller (ESC) hooked up to the motor. I...

Homework Statement 1) A cylinder with an initial volume of 1.5 m3 initially contains water 1 MPa and 200 ° C (condition 1). Container is cooled at constant temperature until the volume is 42% of the initial volume (state 2). The constant temperature process is followed by a constant volume...

Hey everyone, I'm trying to figure out what formula I would use to find the authority a flight control surface (not a wing) would have when deflected. I've been searching and searching for information, but if anyone has done some similar calculations, the help would be greatly appreciated!

If one has a simple variable coefficient process like y'(t) = r(t)*y(t), is there a way to control it to a set point by feedback hitting the variable coefficients in r(t)? I am interested in feedback control of population processes. y'(t) = r*y(t) is simple proportional growth with a...

Hi, i’m looking for some mathematical tools for analysis or classification of solutions of optimal control problems/variational. Equations of motions and optimized function depend on some parameters eg. dX1/dt = f(X1,X2, u1, p1) dX2/dt = f(X1,X2, u2, p2) where X1,X2 are state variables, u1,u2...

Problems of control and automation, help please! 2. What are the 4 classes of programming languages of PLC? 3. How to illustrate the meaning of control system in control and automation system? 4. How to illustrate the major role of CPU in a PLC and what is the major role of CPU? 5...

Homework Statement Your tone control circuit must satisfy the following specifications: 1. peak input signal voltage of 8 V; 2. peak output signal voltage of 8 V; 3. operating frequency range of 20 Hz – 20 kHz (audio band); 4. three tone bands with cut-off frequencies at 200 Hz and 2 kHz...

I'm trying to get the transfer function of this rigid control system that uses rate feedback to stabilize it. Using k=1 and kv=0 Attempt at a solution. When kv=0, the rate feedback is removed. In the block diagram, I moved the pickoff point and used the cascade rule to get 1/s^2 and...