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Airsoft - Capture points (DOMINATION) - Arduino + WiFi

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Airsoft is an outdoor game of radiation to extreme sports. The game is very popular, so it has also served through various styles of play, that is, game modes. Most of them are based on popular FPS titles such as Counter Strike or Call of Duty. From offensive and defensive modes to Free-for-all. One of the most popular modes is Capture Points, or DOMINATION. In this game mode, there are at least two locations that teams are fighting for. The goal of the game is to occupy and maintain both points by one team. Points are placed in a neutral location, for example at the center of the map at the sides, or each at the headquarters of the other team. In order for the game to be fast enough, it is enough to have both points. If it is written on both points (it does not have to keep it after x seconds), the game ends and thus won. To make the game more interesting, I made these two points. Each point contained a hardware page: Arduino Nano/Uno buzzer wifi module nRF24l01 + PA + LNA 2 pu

RFID access system via web interface with ESP8266

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Today I want to introduct my RFID access door system with web interface. Administrator Manages the Web Interface Seeing real-time attachment of card Historically sees the last 100 attachments One click can approve already attached card Manual Card Entry User uses ATM card, ISIC card, meets ISO / IEC 14443 A standard Removing a card Graphical representation of approaches + doorman statistics See source code for NodeMCU User Physically attaches the NFC tag / keyring / bracelet / card If user is verified, door will be opened for 5 seconds When a user is not verified, doors will not open User doesn't have access to web interface System offers: Verify cards and web access to the object The reader reads the ISO / IEC 14443 A card, sends its MAC address to the web, where OK / NO is verified ISIC cards, ATM cards, employee cards can be used In the case of the OK NodeMCU reply, it activates the tab to open the door. From the inside of the building it is possible to o

Water level monitor in waterwell - Arduino / ESP8266 / ESP32

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The water level monitor project is a type of data recording and storage project that can be used for extended daily water level development statistics. This makes it possible to determine the months of the year when there is a lack of water in the wells and the opposite, when there is enough water, or even an excess. It is also possible to integrate extended control of power elements - pumps, waterworks, solenoid valves, which can be used to water the garden and beds - to irrigate or to pump water and use it as a utility for flushing, washing. The basic version project used only logging data to MySQL databases at regular intervals of several minutes. To record the water level (but also the height of another variable, such as snow, coal, wood), I used the ultrasonic distance sensor HC-SR04, which is characterized by high reliability and simple operation and low consumption. It can measure 3-450 centimeters. It uses ultrasound at a frequency of 40kHz with a transmission pulse of 10 micro

Mastermind - Logik (Arduino + LCD 20x4 - I2C)

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Hi, I'd like to introduce today my implementation for Mastermind, also known as Logik. In this implementation, the player does not guess the colors and their order as in the original - desktop version played by two players, but guesses the numbers and their order. It should be stressed that numbers cannot be repeated. The task of determining numbers and their order is Arduino, which generates them. Arduino continues to serve as an experiment counter and receives logic inputs through 5 buttons that switch against the ground (INPUT_PULLUP). Use the buttons to enter the user input in the form of numbers for positions. The last button confirms the entry and sends it to Arduino. In addition to the current user input, the LCD also shows the result. If the user does not guess the number or the position, the display will show the corresponding position - if he guesses the number with the position, = will be displayed; if he guesses the number but not the position, C will be displayed. unco

ESP32 control via UDP datagrams

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Today I would like to point out the possibility of controlling the ESP32 development board by sending UDP messages for easy ON / OFF control. This is one of the easiest ways to send data, process it, and take action based on the information received. ESP32 is a platform that is used in most cases in connection with WiFi connectivity as a webserver or webclient, which connects to a remote server and POST, GET method, or with the integration of the MQTT protocol, sends data to a remote server / guest. Libraries for ESP32 written in C++ Arduino core (framework) also allows to use asynchronous UDP libraries for sending and receiving data. An interesting feature is asynchronicity, as they work in the "background" and the user does not have to program complex functions to accept connections, process information, etc. To send data to the ESP32 development board, we need a simple UDP client. In my case, I used the Windows version of the relatively well-known Packet Sender client. It

IR RPM meter with Arduino

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Arduino is a platform of omnipotence. It allows to create simple flashers, but also complex systems for more advanced automation. Thanks to the different buses, the Arduino can be expanded to include different peripherals. Today we will take a closer look at the obstacle infrared sensor and its use for the tachometer. The sensor principle is very simple. It contains 2 diodes, emitting and receiving diode. The receiving IR diode is connected directly to the 5V digital output, and a potentiometer can be used to control the sensitivity (distance of the object) to which the receiving diode will react. The module is powered by Arduino 5V, it is also used to supply a transmitting IR diode that emits light permanently at 38kHz at a wavelength of 950nm / 940nm (depending on the diode used). The module can be found at retailers (Aliexpress and others) under the name KY-032, respectively Obstacle Sensor. There are several versions, I used the first version, which is constructed very simply. Ther

Currency rate - currconv.com - ESP32 - Webclient

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The currency exchange rate is a very interesting piece of information that can be used in a project with Arduin or a development board from the Espressif platform. There are a number of freely available and documented APIs that can be used to get the current exchange rate of two currencies. For this tutorial, I used the service http://free.currconv.com/, which offers a simple exchange rate of two currencies in JSON format. The user uses his API key and the mentioned currencies in the query to access the exchange rates of those currencies. To get the key just ask via the form on the page, it requires only email. For this tutorial, we'll show the exchange rate between CZK and EUR. I we will count the value of one euro in Czech crowns. The free program currconv service is limited to 60 queries per hour. If it is exceeded, the user is blocked within the next hour. JSON is a data format with a value that belongs to a variable. The variable is enclosed in quotation marks, and the entire