Smart LED Mining Lamp
Most mining activities are conducted deep underground where fatal accidents such as collapse, flooding and gas explosion happen from time to time around the world. So it is necessary to establish an effective monitoring system to ensure the safety of miners. For example, a system that can give an alarm signal for immediate evacuation when dangerous gas leakage is detected, or can search and rescue the miners who are trapped underground after collapse. The solution of smart LED mining lamp introduced in this article is such a system that can work well.
A smart LED mining lamp is composed of two modules, that is, lighting module and a module for gas detection, communication and locating.
The lighting module includes LEDs, reflector, driver, battery and charge management unit. Li-ion battery is the best choice because of its low weight and developed technology of charge management. LED boasts diverse advantages like low power, environment friendly, long service life and explosion proof over traditional lighting sources. LED drivers used in this solution supports dimming function. This function is realized by PWM signal from a MCU in order to implement a software-controlled switch instead of hardware ones that have the possibility of producing spark. National Semiconductor, Analog Device, ON Semiconductor, Linear Technology and Texas Instruments are offering high-performance LED drivers; and Cree, Broadcom, and Optek technology can provide LEDs.
The module for gas detection, communication and locating is made up of an ultra low-power MCU, gas sensor, and ZigBee sub-module. It monitors underground gas level and sends signal to MCU for processing. If gas level is higher than the preset value, the module will give a voice alarm and send alarm signal to remote devices through the ZigBee sub-module. The ZigBee sub-module is an end device in a ZigBee system. It works with the wired or wireless ZigBee network (implemented with ZigBee router or gateway) to broadcast alarm signal and help locate miners' positions. In addition, an underground voice communication between miners can be achieved if microphone, audio codec and amplifier are added to this module.