Hello everyone. I need help with some relay experiment for process identification, i.e to make appropriate scheme in Simulink. I have to put a relay in front of process, and process should start to oscillate(system with negative feedback). After two or three periods of oscillations, I have to find a frequency of oscillations w. Then, I have to "turn off" relay, and continue activation of process with sine wave sin(w*t), w is a frequency which is determined earlier. After few periods I should find new frequency w2 and lead that value to block sin(w*t), and so on until frequency show certain convergence. Every help is welcome. I know how to find frequency, i.e. how to make a scheme which calculates frequency all time. I know how to do it manually with sine wave generator, but it is not problem. All process should be automatic and my main problem is how to take value of that frequency after some periods of time, or after few cycling periods, few zero crossing of process or relay etc. Thank you in advance for any help.
