Team:NCKU Tainan/Temperature

Temperature Sensor DS18B20

About this section, we are showing how to use DS18B20 one wire water proof temperature sensor.


Motivation


Because E. coli is sensitive to temperature sensor. According to the experiment, it grows the best in 37°C (99°F), and its acceptable range is about 22 to 40°C (72 to 104°F). Therefore, we need temperature sensor to monitor our medium's temperature.







Experiments


  • Experiment 1: Temperature measuring

    1. Purpose

      • Because the buffer solution wouldn’t change too much in the environment, we used the buffer solution to calibrate the pH meter to ensure that the deviation would the same every time.

    2. Method

      • We put our temperature sensor into the incubator. We wire the sensor with the LCD to keep it closed.

    3. Result

      • We placed the sensor in an environment of incubator 37 degrees, and the temperature measured by the LCD display sensor was 37.06 degrees. The error is 0.06 degrees, which we think is not big. But in order to make the measured temperature more accurate, we designed Experiment 2 - Temperature experimental curve fitting.

  • Experiment 2: Temperature experimental curve fitting

    1. Purpose

      • Since the error value of the temperature sensing device is not necessarily, we use multiple sampling methods, and then average the values measured in each temperature interval to reduce the error value without excessive error.

    2. Method

      • We use the above method to take 150 strokes as training data, and use the basic accessories of MATLAB to find the appropriate nine temperature model formulas.

    3. Result

      • We found a 7th degree temperature curve to reduce its error. (You can see more information in software temperature.)


    4. Materials used

      1. Arduino UNO

      2. DS18B20 temperature sensor
        1. Power supply range is 3.0V to 5.5V
        2. Measures temperatures from -55°C to +125°C (-67°F to +257°F)±0.5°C accuracy from –10°C to +85°C (14 to 185°F)

      3. a register of 4700 ohms





Wiring






Reference


  1. Konstantin Dimitrov.(2016).Arduino Thermometer With DS18B20. Retrieved from
    https://create.arduino.cc/projecthub/TheGadgetBoy/ds18b20-digital-temperature-sensor-and-arduino-9cc806