Simulink USS block - probability analysis

[MrsZiggy]

Here are the basics - I've got a model with a computed distance between 2 objects. The likelihood that object A will detect object B is a probability dependent on distance (and its a cumulative lognormal curve).

I want to include a probability function based on that computed distance. So that at X meters, the probability of detection is 20%. At Y distance its 50% etc. At each step of the model, the distance will be different, so it needs to redo its random draw from the probability function and output whether or not object B was detected.

I was under the impression that the uncertain state block within the robust control toolbox was the direction to go, but so far I haven't been able to decipher the "help" information to learn how to use and apply it. (And as far as I can understand, it would be ideal b/c I can also run the model varying all the uncertain variables a certain number of times from the command line).

HELP PLEASE!

 

[NateD]

The easiest way to do this is to use the MATLAB Statistics and Machine Learning Toolbox. You can use the function 'lognormcdf' to calculate the cumulative probability of detecting object B given a certain distance. Then, you can generate a random number between 0 and 1 and compare it to the probability output from the lognormcdf function to determine if object B is detected or not. For example, if the distance is X meters, then the probability of detection is 20%. The lognormcdf function will return a value of 0.2 for this distance. Then, you can generate a random number between 0 and 1, let's say 0.6. If the generated random number is less than or equal to 0.2 (the probability output from lognormcdf), then object B is detected; otherwise, it is not detected.