Ultrazvukový anemometr

| Kategorie: Diplomové, bakalářské práce  | Tento dokument chci!

Práce popisuje principy a problémy při realizaci ultrazvukového anemometru. Je popsán princip výpočtu rychlosti větru a následné korekce výpočtu. Pro realizaci jsou využity ultrazvukové sensory a microcontrolér ARM Cortex-M3. Práce se zabývá generováním PWM signálu, jeho analogovou filtrací, zesílením a odvysíláním. Na přijímací straně jeto nízkonapěťový zesilovač a komparátor. Vyvíjený kód je popsán pomocí vývojového diagramu.

Vydal: FEKT VUT Brno Autor: Michael Dvořácek

Strana 31 z 49

Vámi hledaný text obsahuje tato stránku dokumentu který není autorem určen k veřejnému šíření.

Jak získat tento dokument?






Poznámky redaktora
Then adc_ppx_aver and adc_ppy_aver are used for averaging actual adc_pp value. The last what can measured temperature. As input argument are adc_pp variable and addresses adc_ppx_aver, adc_ppy and i variables. don’t measure every cycle we measure when wind speed for axis was updated. Here starts measurement axis. Input arguments are with actual measured time, adc_pp for time correction based peak peak ADC value received signal. Program continue with display initialization. The temp variable serve for temperature measurement. Addresses of tx_array and ty_array are given count time values first position array and keep last averages here. In adc_peaktopeak function calculated ADC peak peak value stored sequence. For calculation ADC sequence peak peak value, adc_pp takes place. Second condition fulfilled after timer interrupt. Here flag variable tested. Forth conditions tests flag measurement results are convenient add actual measured time wind speed calculation. Therefore input argument first field captured ADC sequence. It means that signal was received, it’s triggered timer_post_int function.4. The function returns actual adc_pp value. first adc_sample function stored captured ADC samples adc_array field. first level there are conditions. With first condition pwm_prepare function called.3 Main function Function start with local variable definitions. used capture time from timer, tx_array and ty_array are used buffer time averages from measurements before. The last variables are and serve for counting cycles.4. Then temp variable adjust airspeed constant actual temperature condition. Program continues infinite while loop. When flag doesn’t fulfill any condition, program waiting interrupt. After that initialization functions are called. that moment variable equal to 23 . Then gpio_post_int gives measured time and the time correct range, set flag X_WIND_CALC Y_WIND_CALC state. Then function adc_pp_average called inform us about adc_pp value. With 32th calling this function, new wind speed value calculated. we received signal, third condition fulfilled. Functions inside third condition serve measure received signal and calculate wind speed. The function called with address first field adc_array. Address and variables let know number order this function. see adc_pp averaged value from last ADC sequences. Otherwise set flag measure again with X_PWM Y_PWM state. first line the display printed application name