Recent content by synMehdi

I would like to undertand more the force caused by unbalance in a rotor, assume that the bearing is represented with 2 springs like above: The geometrical center of the rotor ##O## is equivalent to it center of gravity ##C_g## and the center of the stator (bearing) ##O'## The rotor is perfectly...

Great answer, I understand more my problem. let's see: Hmm yes, but I may have not used the right word by saying independent, what I mean is that they are approximations. Let's say that the system is just ##a\cdot x=b## and i have: $$a\cdot x_1 = y_1 \\ a\cdot x_2=y_2$$ I agree that if...

Thank you, but I'm not able to prove what I've done or if the approach is correct. Well, ##[X] _{m \times p} ## is of rank ##m## because ##p>=m## and all ##p## equations are independent. For the type of solution I would say mathematical for the rigorous understanding but the goal is to make...

Summary: I need to Identify my linear model matrix using least squares . The aim is to approach an overdetermined system Matrix [A] by knowing pairs of [x] and [y] input data in the complex space. I need to do a linear model identification using least squared method. My model to identify is a...

Well I thought multipliers were for equality constraints not inequality. Can they be used in this case? I now understand what you were proposing and it is a good idea, like an infinity penalty for going outside the bounds of ##u(t)##, right?. I will see at the maths of it, try it and get back.

Thanks for the answer. The solution that you propose seems difficult to include analytically. My question is more about how the Pontryagin Minimum Principle works when whe have constraints. I suppose that ##\frac{dH}{du} = 0## is no longer valid so I will have to look in the borders...

Hi, I am trying to solve a control problem where I have to minimize the fuel consumption of a vehicle: $$J=\int_{0}^{T} L(x(t), u(t),t) + g(x(T),T)dt$$ ##L(u(t),v(t))=\sum\limits_{i,j=0}^{2} K_{i,j} u(t)^i v(t)^j ## is convex (quadratic) and the term ##g(x(T),T)## is to have a constraint in the...

Can you please further explain what do you mean? If I simply apply the Pacejka model and my understanding of it. If my torque is bigger than the traction force. I will end having no vehicle acceleration and only wheel acceleration.

Hi, I'm simulating the behavior of a car and I have some troubles with the tires. Specially with slip when the car is accelerating. I've seen many documents over the internet and I understood 2 main things: Wheel slip is necessary to accelerate & the coefficient of friction depends on the slip...

Hello, I'm a mechanical engineering student and I'm working in traction control for Formula 1 cars. The traction control in the cars is simple, too simple: an engine cut is done when the engine is at a certain RPM and slip value. A matrix of four values of RPM and slip has to be provided to...

Hi, I have a question concerning car front suspension geometry/design like the macPherson suspension. I would like to know the influence of geometrical factors in the suspension behaviour. The factors in which I'm interested are : spring/damper angle, spring/damper position relative to the wheel...

Hi, I'm a beginner in mechanics so I need some help with a project I started. My project consists of a small kart-like car. The car will be Rear-Wheel-Drive and Rear-Engine too (RR layout). and I am willing to use a small 110cc moped engine. I have a trike Differential Gear for the rear shaft...

Thank you for your help I want the IF frequency to be around 2Mhz, I'm going to sample it so it is going to be a digital demodulating. I think that what I want is named a diversity or a MIMO receiver because I want two antennas and a dual LNA/Mixer, do you know a good one suited for me like the...

Those are really bad news. what i need is a dual LNA and downconverter Tu operate around 900Mhz... Are you saying that the LNB can possibly not work in lower frequencies? (Assuming that I take off the filters..) If not.. what can I use?

The VCO replaces all the oscillator in the LNB. Isn't just simpler and cheaper to replace the resonator?