Developing simulations for the Missile Defense Agency - Advanced Technology group

30+ years experience in missiles, smart munitions and other aerodynamic systems. Specializing in systems engineering, aerospace systems design, simulation and modeling, aerodynamics, and numerical analysis.

Answered

Ballstic Impact of Bullets on armor

I don't know af any specific ballistics tools. You should browse the a list of Matlab products at this link: Matlab Products

Ballstic Impact of Bullets on armor

I don't know af any specific ballistics tools. You should browse the a list of Matlab products at this link: Matlab Products

4 days ago | 0

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Answered

How to find theta and theta dot in a simple pendulum simulation in MATLAB.

I'm not sure at all what your system equations are. The first rule of dynamics is where you have translational modes of motion ...

How to find theta and theta dot in a simple pendulum simulation in MATLAB.

I'm not sure at all what your system equations are. The first rule of dynamics is where you have translational modes of motion ...

11 days ago | 0

Answered

What is a "system variable" in a Simulink model?

In this context, the "system" is the device that you are modelling. Therefore, a "system variable" is one of the variables in y...

What is a "system variable" in a Simulink model?

In this context, the "system" is the device that you are modelling. Therefore, a "system variable" is one of the variables in y...

12 days ago | 1

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Answered

Undefined function 'simset' for input arguments of type 'char'.

simset is an obsolete function. See documentation here. It says to use the Configuration Parameters dialog box.

Undefined function 'simset' for input arguments of type 'char'.

simset is an obsolete function. See documentation here. It says to use the Configuration Parameters dialog box.

12 days ago | 0

Answered

Newtons method for finding minimum of a function.

Here is another variation; function [f,g,h] = myfunction(x) f1 = @(z) exp(2*sin(z))-z; %function dx ...

Newtons method for finding minimum of a function.

Here is another variation; function [f,g,h] = myfunction(x) f1 = @(z) exp(2*sin(z))-z; %function dx ...

13 days ago | 0

Answered

help me in trying to solve the secant method

Try preallocating x, right after you define n: n = 100; x = nan(1,n); ...

help me in trying to solve the secant method

Try preallocating x, right after you define n: n = 100; x = nan(1,n); ...

13 days ago | 0

Answered

trying to calculate the central diff approximation

There is a Matlab function "diff" which will do this. Otherwise, your subscripts must all match (2:end-1) Adi_1 = diff(Vdi_1...

trying to calculate the central diff approximation

There is a Matlab function "diff" which will do this. Otherwise, your subscripts must all match (2:end-1) Adi_1 = diff(Vdi_1...

13 days ago | 0

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Answered

Performing calculations (Newton's method) over values in loop

Yes, your loop is not quite right. Notice your placement of the three lines i=1; converge = false; po = p_init(1); These t...

Performing calculations (Newton's method) over values in loop

Yes, your loop is not quite right. Notice your placement of the three lines i=1; converge = false; po = p_init(1); These t...

14 days ago | 0

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Answered

Draw a circle for arbitrary orientation on spherical surface

My approach is to define the circle around the X-axis, then rotate it into the desired position through a Yaw-Pitch rotation. ...

Draw a circle for arbitrary orientation on spherical surface

My approach is to define the circle around the X-axis, then rotate it into the desired position through a Yaw-Pitch rotation. ...

16 days ago | 1

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Answered

the meaning of basic matlab words

an argument is a constant or variable that you provide to a function; e.g. sin(x) % here x is the argument to the function sin...

the meaning of basic matlab words

an argument is a constant or variable that you provide to a function; e.g. sin(x) % here x is the argument to the function sin...

17 days ago | 0

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Answered

How to alter Comet Speed

I don't see a way to control the speed of the comet function. There is a discussion of controlling the speed of an animated lin...

How to alter Comet Speed

I don't see a way to control the speed of the comet function. There is a discussion of controlling the speed of an animated lin...

17 days ago | 0

Answered

Incorrect Answer Calculated For Force Calculation

It is assumed that you want to find F3 and y such that the system is in equilibrium (this is not stated) (and I disagree with D...

Incorrect Answer Calculated For Force Calculation

It is assumed that you want to find F3 and y such that the system is in equilibrium (this is not stated) (and I disagree with D...

18 days ago | 0

Answered

Transformation Matrix Between Two Cartesian Systems

This is a very generic question and there are many ways to answer. It depends on what information you have about the two coordi...

Transformation Matrix Between Two Cartesian Systems

This is a very generic question and there are many ways to answer. It depends on what information you have about the two coordi...

26 days ago | 0

Answered

Why is ode45 changing the value of the state variable between calls to my dynamics function?

ode45 implements the Dormand-Prince method which is an embedded 4th / 5th order Runge-Kutta method. For every "step" in the sol...

Why is ode45 changing the value of the state variable between calls to my dynamics function?

ode45 implements the Dormand-Prince method which is an embedded 4th / 5th order Runge-Kutta method. For every "step" in the sol...

27 days ago | 0

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Answered

Implement friction into a model, related to the velocity. (Missile Launch)

This question is familiar. look here.

Implement friction into a model, related to the velocity. (Missile Launch)

This question is familiar. look here.

28 days ago | 0

Answered

How to make a marker circle bold?

plot(x, y, 'ro', 'linewidth',2);

How to make a marker circle bold?

plot(x, y, 'ro', 'linewidth',2);

30 days ago | 0

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Answered

how can i resolve this equation Runge kutta method

Ths is the equation for a parabola. y'' = -1 y' = -y y = -1/2 y^2 No need for a numerical approximation.

how can i resolve this equation Runge kutta method

Ths is the equation for a parabola. y'' = -1 y' = -y y = -1/2 y^2 No need for a numerical approximation.

1 month ago | 0

Answered

Missile Lauch friction gamma factor - Output deviating from desired output, please help!

Step 1: Draw a free body diagram that shows the body with all of the forces that act on it and the coordinate frame(s) that are...

Missile Lauch friction gamma factor - Output deviating from desired output, please help!

Step 1: Draw a free body diagram that shows the body with all of the forces that act on it and the coordinate frame(s) that are...

1 month ago | 0

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Answered

How to calculate the slope from geopraphical coordinates?

First of all, you should consider the relationship between the WGS84 lat/lon/alt and the ECEF frame. Altitude is perpendicular ...

How to calculate the slope from geopraphical coordinates?

First of all, you should consider the relationship between the WGS84 lat/lon/alt and the ECEF frame. Altitude is perpendicular ...

1 month ago | 1

Answered

calculate rotation matrix in 3D

I'll assume that we make the reference frame right-handed by negating the axis_3 vector such that axis_1 = [2.7239 -0.2014 -...

calculate rotation matrix in 3D

I'll assume that we make the reference frame right-handed by negating the axis_3 vector such that axis_1 = [2.7239 -0.2014 -...

2 months ago | 1

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Answered

Translational motion of a rotating object.

To begin, Chasles' theorem states that translational motion and rotational motion obey the law of superposition. Therefore, you...

Translational motion of a rotating object.

To begin, Chasles' theorem states that translational motion and rotational motion obey the law of superposition. Therefore, you...

2 months ago | 0

Answered

change variable value based on other variable in if loop

Your input command is requesting a string input: in1 = input('first: ','s'); in2 = input('second: ','s'); This results in in1...

change variable value based on other variable in if loop

Your input command is requesting a string input: in1 = input('first: ','s'); in2 = input('second: ','s'); This results in in1...

2 months ago | 1

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Answered

I don't know the problem involved Backward difference.

I am assuming that your question is that you don't understand Simpson's rule. Below is an exerpt from Wikipedia: Simoson'...

I don't know the problem involved Backward difference.

I am assuming that your question is that you don't understand Simpson's rule. Below is an exerpt from Wikipedia: Simoson'...

2 months ago | 0

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Answered

1-2-1 or X-Y-X rotation matrix not supported

I recently cataloged all of the permutations of the 2 and 3 axis planar rotations. It is easy to write your own functions. See...

1-2-1 or X-Y-X rotation matrix not supported

I recently cataloged all of the permutations of the 2 and 3 axis planar rotations. It is easy to write your own functions. See...

2 months ago | 0

Answered

Extracting data from simout MATLAB work space

simout is a timeseries structure. I like to extract separate vectors from the structure, for example: t = timout.time(simout.t...

Extracting data from simout MATLAB work space

simout is a timeseries structure. I like to extract separate vectors from the structure, for example: t = timout.time(simout.t...

2 months ago | 0

Answered

Where can I publish Matlab-compiled software?

If you want to share the source code, you can post it on Matlab File Exchange

Where can I publish Matlab-compiled software?

If you want to share the source code, you can post it on Matlab File Exchange

2 months ago | 0

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Answered

In my Simulink model I would like to conditionally write output data to selectable .mat files in different relative directories.

This sounds like a rather sophisticated way of constructing output. I'm not sure if that is easily acomplished with the "to fil...

In my Simulink model I would like to conditionally write output data to selectable .mat files in different relative directories.

This sounds like a rather sophisticated way of constructing output. I'm not sure if that is easily acomplished with the "to fil...

2 months ago | 0

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Answered

minimum feret diameter of particle

https://blogs.mathworks.com/steve/2018/02/20/minimum-feret-diameter/?s_tid=answers_rc2-1_p4_MLT

minimum feret diameter of particle

https://blogs.mathworks.com/steve/2018/02/20/minimum-feret-diameter/?s_tid=answers_rc2-1_p4_MLT

2 months ago | 0

Answered

Vlookup equivalent function for matlab

If your data is in a 2D table (matrix) and you want to locate a column that matches the exact value from another column, then lo...

Vlookup equivalent function for matlab

If your data is in a 2D table (matrix) and you want to locate a column that matches the exact value from another column, then lo...

2 months ago | 0

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Answered

How calculate the second and third numerical derivative of one variable f(x)

The Matlab "diff" function is basically the Backward difference formula. There are much more accurate ways to compute numerical...

How calculate the second and third numerical derivative of one variable f(x)

The Matlab "diff" function is basically the Backward difference formula. There are much more accurate ways to compute numerical...

2 months ago | 0