SMS Garage Alert system using an Ultrasonic sensor

I've bought another USB-Charger for my project, because this Wall socket battery charger is unreliable. Twice my project stopped working using 2 of these and one of these chargers even got damaged.

I've bought this USB Charger instead from a local electronics shop named Conrad. This one seems to be more reliable, because my project is running for at least 3 weeks now without a hitch! I've also updated the components list.

And the testing phase is over! I've implemented the code from Log 2 into my sketch. You can also take a look at the code in the section Project code. The new sketch can be downloaded in the files section. The D1 Mini should consume less power now, when the watchdog isn't active. I will measure the actual currents on the weekend, when I'm less tired.  I'm really busy at the moment, because I'm doing an advanced training in the field of geoinformation systems (GIS) so please bear with me. 

Currently I'm trying to reduce the power consumption of my project setup by turning the WiFi module off, when it's not needed, thus during the time period were the watchdog isn't active. I'm testing my new code at the moment.

The following functions are essential for achieving my goal:

// function for turning the WiFi module off
void stopWiFiAndSleep() {
  WiFi.disconnect();
  delay(1000);
  WiFi.mode(WIFI_OFF);
  WiFi.forceSleepBegin();
  delay(1);
  Serial.println("WiFi module disabled...");
}

Why delay(1000)? If you want to know why, click on the link. :) I had the same problem and the suggestion of ardyesp fixed it.

// function for wake up and starting WiFi connection
void startWiFiAndWake() {
  WiFi.forceSleepWake();
  delay(1);
  // Bring up the WiFi connection
  WiFi.mode(WIFI_STA);
  WiFi.begin(WLAN_SECRET_SSID, WLAN_SECRET_PASS);
  while (WiFi.status() != WL_CONNECTED)
  {
    delay(500);
    Serial.print(".");
  }
  Serial.println();
  Serial.print("WiFi Connected, IP address: ");
  Serial.println(WiFi.localIP());
}

Till next time!

I've removed the mechanical timer switch from my original project setup to reduce one potential weak point. The downside is, that the Wemos D1 Mini is running all day every day now.  Furthermore I've changed my project code, which was required after removing the timer switch from the setup. With the new code it's also possible now to check out  the sensor measurements in a web browser on your comfy couch! :)

I've looked for a data sheet for the Wemos D1 Mini, but I couldn't find one. I've found a data sheet for the ESP8266 at least.  Even with a current consumption of 170 mA (in the worst case scenario in regards to the WiFi connection) and an operating Voltage of 3.3 V it seems the project is still financially reasonable (1.47 Euro per year). I will check out the consumption of my project setup in the next few days. 

Also I've found out about this waterproof ultrasonic sensor, which I wasn't aware of. I just ordered that one. I would definitely recommend this one for areas, which are colder and more humid (like a garage) to guarantee, that your sensor isn't decaying quite so fast. I will test the sensor I'm using right now though to get an idea about how reliable this one is in a harsher environment. I will do updates on this topic in the future.