Determine speed from hall sensor output

Hello,

I am working on a student project and want to calculate the RPM of the wheels and thus the speed of the vehicle using a hall sensor. Assuming the hall sensor output can be simulated as a block signal with a varying pulse interval as the speed changes, how can I determine the time t(n)-t(n-1) where n indicates the occurence where the output signal rises above a threshold value for a continous signal? In other words: I want simulink to scan a continous input signal and output the time difference between the two most recent peaks.

Any help is appreciated. Thanks.

[ANGETI JIVAL]

please i have a similar problem i need help too. am using brushless dc motor with 3 hall effect sensor. i need to get speed from the hall sensor so as to feedback in a simulnk arduino. i am implementing fuzzy PID on arduino uno board. please i need help urgent in orther to help me complete my thesis. am a master student in control and intrumentation. thanks.

[ROYAL SUTNGA]

Please I am having the same problem. I want matlab code for calculating the speed and position of the motor using the signals of the hall sensors.Thanks.

Answer 1

[Vineeth Kartha]

Hi Robin,

Please go through the model that I have attached ' DifferenceofPeaks.mdl' and see if this works for you. An explanation of the model is also provided.

[Robin Egberts]

Hello Vineeth,

Thanks for your help. I am looking for the time difference between the two peaks, the actual peak height different is of no practical concern. I can see how this might work within your model, but I would need to make input a en b continously running time signals for this, such that output(a-b) corresponds to the time difference. I am not sure how to do this... ;-)

Edit: Might it be possible to use a counter with a given sample time to count the instances where the input rises above the threshold and divide the sample time by the amount of counts to give an average time difference?

[ROYAL SUTNGA]

Sir, can you send me the matlab code for calculating the speed and position of the motor using the three signals of the hall sensors.