Under the advocacy of the international community, more and more research topics have been built around the ocean. This paper proposed an implementation scheme of marine wireless sensor network monitoring system based on LoRa and MQTT. Different from the traditional network architecture, the system was constructed by combining with two network forms, and according to their respective characteristics, the overall design followed the transition from LoRa to MQTT. We first used LoRa to interconnect the sensor nodes with the gateway, and on this basis, the collected data was sent to the server visualization platform through MQTT, the backend management server would continuously refresh the monitoring page. At the same time, the client could use a browser-based web application to directly access and call data for global maritime information monitoring. In the future, we will further improve the system and optimize the algorithm, to achieve more dimensions and deeper exploration of the underwater world.

MQTT protocol is a publish/subscribe message protocol based on TCP/IP protocol. It has the characteristics of low power consumption, scalability, openness and simplicity. HTTP protocol is an open and low-cost request/reply message protocol based on TCP/IP protocol. It is the main protocol of Internet communication, but it is not suitable for the environment of computing, processing and bandwidth limited. In this paper, a simplified wireless sensor network node was designed based on MQTT protocol. The node was designed to use the Arduino development environment and use the WiFi for networking. It has the characteristics of simple structure, low power consumption and so on. The design can be widely used in smart home, environmental monitoring and medical applications, and is the main contents of the Internet of things (IoT).

No abstract

With the rapid development of somatosensory controller, it is more and more difficult for traditional man-machine interaction to meet people's needs. So designing a robotic arm with gesture control, Leap Motion controller can be used to replace the traditional man-machine interaction mode. And collect hand data, after the gesture is analyzed and processed by computer, transmitted by ZigBee to the Arduino board, then robot arm is controlled to grasp objects by mimicking the movements of a human hand. The experimental results show that the system can control the robot arm in real time and simulate most of the movements of human arm more accurately, robot arm can be controlled remotely for rotating, grasping and other tasks. It can be applied to most situations that serve human life.

No abstract