Jim Riggs
Missile Defense Agency - Advanced Technology Group
Developing simulations for the Missile Defense Agency - Advanced Technology group
30+ years experience in missiles, smart munitions and other aerodynamic systems.
Contribute at least one answer each month for 36 consecutive months
Awarded to Jim Riggs on 02 Dec 2020
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Awarded to Jim Riggs on 06 Aug 2019
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Awarded to Jim Riggs on 07 Jul 2018
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How to connect the two signals in one signal in MATLAB Simulink? I mean first signal finishes second signal starts.
You description of the problem is confusing to me, bu the statement in the title "first signal finishes second signal starts" ...
How to connect the two signals in one signal in MATLAB Simulink? I mean first signal finishes second signal starts.
You description of the problem is confusing to me, bu the statement in the title "first signal finishes second signal starts" ...
9ヶ月 前 | 0
回答済み
Numerical Integration in Matlab
There seem to be two problems: 1) your function "fun" returns "NaN" at zero, so you cannot integrate starting from zero. You n...
Numerical Integration in Matlab
There seem to be two problems: 1) your function "fun" returns "NaN" at zero, so you cannot integrate starting from zero. You n...
10ヶ月 前 | 0
| 採用済み
回答済み
Simulink counter block having an initial starting value of -1
Yes, the two counter blocks in the library do not allow you to set the initial value. Whenever I need to use a counter, I usual...
Simulink counter block having an initial starting value of -1
Yes, the two counter blocks in the library do not allow you to set the initial value. Whenever I need to use a counter, I usual...
10ヶ月 前 | 1
| 採用済み
回答済み
Finding the roots of an equation using Newton-Raphson method but I don't know the equation!
You use a numerical approximation for the derivative. Start at some initial guess for x & y. take a small step, and compute th...
Finding the roots of an equation using Newton-Raphson method but I don't know the equation!
You use a numerical approximation for the derivative. Start at some initial guess for x & y. take a small step, and compute th...
10ヶ月 前 | 1
回答済み
Implementing Angles as an input in Simulink
It appears (based on the icon on the block) that the block labeled "Robot Controler" is a Matlab function block. In order to a...
Implementing Angles as an input in Simulink
It appears (based on the icon on the block) that the block labeled "Robot Controler" is a Matlab function block. In order to a...
10ヶ月 前 | 0
回答済み
Pendulum using Runge Kutta
Yes, there are a few things wrong with this code. James Tursa has identified one obvious error. Another problem is with the lo...
Pendulum using Runge Kutta
Yes, there are a few things wrong with this code. James Tursa has identified one obvious error. Another problem is with the lo...
11ヶ月 前 | 0
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回答済み
How to return the index of time steps in Simulink?
One way to do this is to put a step counter in the block. This will keep track of the number of times the block is executed. T...
How to return the index of time steps in Simulink?
One way to do this is to put a step counter in the block. This will keep track of the number of times the block is executed. T...
11ヶ月 前 | 0
回答済み
Why is my code not working?
Not entirely sure if this is the reference in the error message, but this line has unballanced parentheses: f = (1/(t-t^(-1))*...
Why is my code not working?
Not entirely sure if this is the reference in the error message, but this line has unballanced parentheses: f = (1/(t-t^(-1))*...
12ヶ月 前 | 0
回答済み
SIR Simulink Model Function Block
In the Simulink library browser, on the "sources" pallet, you will find a "clock" function. Use this to create a time signal. ...
SIR Simulink Model Function Block
In the Simulink library browser, on the "sources" pallet, you will find a "clock" function. Use this to create a time signal. ...
約1年 前 | 0
回答済み
How can one do this calculation?
Look into using logical indexing. Not my strong point, but for example, if A is the 3 x 10 matrix, you can select all cases whe...
How can one do this calculation?
Look into using logical indexing. Not my strong point, but for example, if A is the 3 x 10 matrix, you can select all cases whe...
約1年 前 | 0
回答済み
Kalman Filtering for smoothing GPS speed data
The problem is with this line: P = (1-KG)*P; This causes the gain P to continuously decrease. After a while, the gain P is ve...
Kalman Filtering for smoothing GPS speed data
The problem is with this line: P = (1-KG)*P; This causes the gain P to continuously decrease. After a while, the gain P is ve...
1年以上 前 | 1
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numerical derivate and central difference
Here are some Numerical difference formulas using the central difference method (substitute dt = h). You can find more formulas...
numerical derivate and central difference
Here are some Numerical difference formulas using the central difference method (substitute dt = h). You can find more formulas...
1年以上 前 | 1
回答済み
Meaning of the following: function [y1,...yn] = input()
It simply means that there are no user inputs to this function. The long list of variable names are returned from the function....
Meaning of the following: function [y1,...yn] = input()
It simply means that there are no user inputs to this function. The long list of variable names are returned from the function....
1年以上 前 | 0
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Angle Between two vectors.
Given two vectors A and B, the dot product of the two vectors (A dot B) gives the product ABcos(ang), so to get just the angle, ...
Angle Between two vectors.
Given two vectors A and B, the dot product of the two vectors (A dot B) gives the product ABcos(ang), so to get just the angle, ...
1年以上 前 | 0
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Is it possible to summarize this code?
You could use a switch case structure, that would be a bit more compact. it would look like this: switch davar1.CC_CHECK ...
Is it possible to summarize this code?
You could use a switch case structure, that would be a bit more compact. it would look like this: switch davar1.CC_CHECK ...
1年以上 前 | 2
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help fixing the Heuns method
Heun's method is otherwise known as "explicit trapezoidal method", "improved Euler's method" or "modified Euler's method". Th...
help fixing the Heuns method
Heun's method is otherwise known as "explicit trapezoidal method", "improved Euler's method" or "modified Euler's method". Th...
1年以上 前 | 0
回答済み
I need help coding a human cannonball ignoring air resistance
Assuming zero drag and relatively low muzzle velocity ( acceleration due to gravity = constant), the point-mass trajectory can b...
I need help coding a human cannonball ignoring air resistance
Assuming zero drag and relatively low muzzle velocity ( acceleration due to gravity = constant), the point-mass trajectory can b...
1年以上 前 | 1
回答済み
Runge Kutta 4th Order Method
I think the problem is the T argument. in k1 you have a capital T, which is a 3-vector in k2, k3, and k4 it is a lower case t,...
Runge Kutta 4th Order Method
I think the problem is the T argument. in k1 you have a capital T, which is a 3-vector in k2, k3, and k4 it is a lower case t,...
1年以上 前 | 0
回答済み
Matlab Homework that im struggling with
To prompt a user to enter a value, try: x = input('Enter the number of equations (from 2 to 5): \n')
Matlab Homework that im struggling with
To prompt a user to enter a value, try: x = input('Enter the number of equations (from 2 to 5): \n')
1年以上 前 | 0
回答済み
I need help with this script
Try this: T = input('Enter your temperature') if T<=96 disp('You are either hypothermic or a zombie') elseif T<99 d...
I need help with this script
Try this: T = input('Enter your temperature') if T<=96 disp('You are either hypothermic or a zombie') elseif T<99 d...
1年以上 前 | 0
回答済み
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
1年以上 前 | 0
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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 ...
1年以上 前 | 0
回答済み
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...
1年以上 前 | 1
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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.
1年以上 前 | 0
回答済み
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 ...
1年以上 前 | 0
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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); ...
1年以上 前 | 0
回答済み
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...
1年以上 前 | 0
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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...
1年以上 前 | 0
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回答済み
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. ...
1年以上 前 | 1
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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...
1年以上 前 | 0
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