ABSTRACT

In this chapter, the authors discuss a small robot that detects heat radiation from a fire, moves towards the heat source, and starts beeping once it reaches the source of the radiation. They require the robot to either move autonomously, or to be manually controlled by remote controller. The authors base the hardware of the robot on a ready-made chassis with two DC motors and an on-board battery pack with five AAA cells providing up to 7.5 V. The remote control is based on a second NodeMCU. It connects to the WLAN spanned by the first NodeMCU on the robot and to the server running on it. On the remote controller they connect MCP3408 8-channel ADC via SPI to the NodeMCU, and set the input voltages of the analog-to-digital converter channels with two joysticks, two potentiometers, several voltage-dividers, and two switches. Testing for ADC values progresses from smaller to larger values, such the buttons are prioritized in a natural way.