Wireless stem flow sensor and its control method

Abstract

The invention relates to a wireless stem flow sensor and a method for controlling the same. The sensor comprises a sensing parameter acquisition unit and a wireless on-chip system, wherein the sensing parameter acquisition unit comprises a heating element clamped on the surface of a stem, and an upstream temperature sensor and a lower downstream temperature sensor which are symmetrically arranged with the heating element as a center and acquire an upstream temperature electrical signal and a downstream temperature electrical signal of the stem respectively; the wireless on-chip system comprises a microcontroller; and according to the upstream temperature electrical signal and the downstream temperature electrical signal, the microcontroller acquires and temporarily stores stem flow data in an on-chip memorizer by a thermal equilibrium method, receives an inquiry instruction and sends the stem flow data out; and a wireless radio-frequency unit receives various instructions sent by an upper computer of a wireless sensing network, retransmits the instructions to the microcontroller, receives the stem flow data sent by the microcontroller and sends the stem flow data to the upper computer by the wireless sensing network. The method adds the wireless sensor to the wireless sensing network and carries out dormancy, the sending of the stem flow data and the adjustment of acquired frequency according to various instruction sent by the upper computer. The equipment is simple, accurate and convenient to manufacture and utilizes a wireless mode to reduce wiring cost.

Description

technical field [0001] The invention relates to the field of sensor technology, in particular to a wireless stem flow sensor and a control method thereof. Background technique [0002] Water is not only an important part of plants, but also an important ecological factor for plant growth and development. Plants change water from a liquid state to a gaseous state, take away heat, and keep the leaf temperature relatively stable in order to grow normally. Most of the water absorbed by plants is consumed in the form of transpiration, so transpiration is a very important factor of plant physiological information, and it is very meaningful to measure and study it. [0003] In the field of plant physiology, the transpiration of plants can be calculated by measuring plant sap flow. The main methods for measuring plant sap flow include heat pulse method, heat diffusion method and heat balance method. Most of the heat pulse method and heat diffusion method use intrusion Type heat so...

AI Technical Summary

Problems solved by technology

However, due to the fact that multiple pairs of temperature sensors are used in the upstream and downstream positions of the heating element in this technical solution, although the measurement accuracy is improved, the power consumption is relatively large, and the cost of the entire stem flow sensor is also increased. The function of the flow meter is also relatively single and lacks flexibility

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