I want to change the scope axes from radian to degree
MATLAB Simulink shows radian (the axes by default).
I want to change this from rad to degree. Thanks.
Use the R2D block for converting from Radians to Degrees after you calculate alpha_m. If you want to do the conversion by yourself, then just add a Gain block with gain equal to 180/pi instead.
Or:
Related
I'm trying to convert from quaternion to row pitch yaw using the as_euler() function, but I don't know which sequence to choose as the parameter "zyx", "xyz", "zyz", etc
Also what is the order of the output euler angles? Is it going to be [roll, pitch yaw] or [yaw, pitch, roll]?
Much thanks!
Yaw, pitch, roll axes are used for rotation around its principal axis sequentially. there exist twelve possible sequences which are;
Proper Euler Angles "z-x-z, x-y-x, y-z-y, z-y-z, x-z-x, y-x-y"
Tait–Bryan angles "x-y-z, y-z-x, z-x-y, x-z-y, z-y-x, y-x-z"
Most common usages is z-y-x in Tait-Bryan angles. "yaw" means rotate around z axis, "pitch" means rotate around y axis, "roll" means rotate around x axis.
If you use z-y-x order the euler-angles order is [yaw, pitch, roll]. You must choose the order depending on what field you work in.
I made the wrap angle code in the Modelica like below.
thetta_eq=mod(thetta, 720);
thetta keep increasing 0 to infinite angle and thetta_eq is the wrapped angle 0 to 720deg.
However, the problem is occurring when i differentiate the wrapped angle.
Furthermore, i'm not able to use the wrapangle block in the Modelica Standard Library 3.2.3 because i have to use 3.2.2 version.
Does anyone have solution for this problem? Code, Logic or options?
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I already know that it's not possible to differentiate when angle drops 720 to 0 deg, because it's discontinuous.
So, What i'd like to ask was making it continuous even the falling region.
Acutually, above picture is sigmoid function and i thought i can use this function when the wrap angle falls 720 to 0 deg.
If i make the sigmoid function's inclination really high, i thought this can be functioning like original wrap angle. And the derivative is not infinite or -infinite so it can be differentiated.
How do you think? and How can i make the logic for this idea?
ps) I really appreciate your reply!
Like matth commented, you can not differentiate a variable with discontinuities.
What would you expect for the derivative when theta jumps from 720 to 0?
Instead of using the wrapped angle, you can use the derivative of the original angle.
model Demo
Modelica.SIunits.Angle theta = 100*sin(time);
Modelica.SIunits.Angle theta_wrap;
Modelica.SIunits.AngularVelocity w;
equation
w = der(theta);
theta_wrap=mod(theta, 2*Modelica.Constants.pi);
end Demo;
Note: I used the proper SIunit type for theta, so I have to wrap to 2*pi radians, instead of 720 degree.
I'm trying to plot the output angular velocity of a Universal Joint relative to it's input angel which I call phi (in the link above phi= landa_1).
I'm using MATLAB to do this
please note the translations of the notation in the link and my code that is:
beta=Beta, phi=landa_1, Omega_2=Omega_B, Omega_1=Omega_A
here is my code:
clear all, close all, clc
phi=0:360; % one rotation of the input shaft
Beta=60;
Omega_A=1;
Omega_B=(Omega_A*cos(Beta))./(1-((sin(Beta))^2)*((cos(phi)).^2))
plot(phi,Omega_B,'LineWidth',2), grid on
BUT! the plot is not what it should look like (which is available in the link above)
My current plot
You need to convert degree to radian in order to use sin and cos. So
clear all, close all, clc
phi=0:360; % one rotation of the input shaft
Beta=60;
Omega_A=1;
Omega_B=(Omega_A*cos(Beta/180*pi))./(1-((sin(Beta/180*pi))^2)*((cos(phi/180*pi)).^2))
plot(phi,Omega_B,'LineWidth',2), grid on
Output:
I have an array of different length measurements to the walls of an arbitrarily shaped box from a point. They are taken during a 360 degree rotation and I also have a degree measurement.
Distance(1:k); % distance to wall of arbitrarily shaped box during a rotation
Degree(1:k); % degrees rotated from first measurement
Time(1:k); % time passed since first measurement
How can I used distance and Time/Distance to plot a shape that would look like the shape of the box? I tried the convhull function, wondering if there are better options.
Would this do the trick?
Rads=Degrees*(2*pi/360);
X=Distance.*cos(Rads);
Y=Distance.*sin(Rads);
plot(X,Y);
I have a very basic question. I am analyzing a movie. In the movie I am fitting a curve to define an object and computing the first derivative of a curve at it's starting point. The first derivative is changing in each frame. I want to measire the first derivative in the from of angle given in degrees or radians. Is there a faster way to do it in MATLAB.
I know its a very simple question, but if someone can explain me the concept then that would be very helpful. Thanks
The derivative of the curve is defined as dy/dx the ratio between the change in X direction and Y direction. This ratio is also the tan of the angle between the curve and the X axis. Therefore, if you want the angle (in radians) all you need it compute atan of the derivative.