日光温室前屋面覆盖物协调铺卷装置设计与试验

Design and Experiment of Coordinative Operation Device of Covers on Front Roof of Chinese Solar Greenhouse

前屋面是实现日光温室内外环境沟通的重要构建部分,通过控制前屋面覆盖物状态即可达到控制日光温室内部环境的目的。保温卷帘、通风卷膜以及遮阳网布作为日光温室常见的3种主要覆盖功能材料,在依靠共同前屋面构造面实现铺卷动作时,存在作业机械结构难以协调、自动化程度低等问题。结合3种覆盖物铺卷的功能需求,设计其彼此相协调的铺卷装置,包括外侧铺卷结构和内侧铺卷结构两个主要部分以及相配套的覆盖物协调铺卷控制方法。通过比例缩放的实体模型和实地试验相结合的方法验证了所设计日光温室前屋面覆盖物协调铺卷装置可以有效实现卷帘、卷膜和遮阳网布3种覆盖物的协调铺卷,且具有较好的控制精度和稳定性。模型试验结果表明:覆盖物开度控制的平均相对误差均小于3.5%,均方根误差均小于2.0%。覆盖物铺卷控制在各个开度下的变异系数均小于3.0%。而卷帘铺卷控制装置在实地试验中,其开度控制试验结果的平均相对误差均小于2.5%,均方根误差小于1.26%,测试数据的变异系数小于1.0%,也表现出较好的作业控制精度和稳定性。实地试验和模型试验结果中的测量数据整体变化趋势相同,进一步验证了装置模型试验结果的合理性和整体装置的实施可行性。

The front roof is an important part of realizing the communication between the internal and external environment of the Chinese solar greenhouse(CSG).The internal environment of CSGs is controlled by the state of the front roof covers in actual production.Three important covers(insulation quilt,transparent film and colored mesh)are laid on the arc-shaped front roof to control the internal environment factor of CSGs,such as the light,temperature and humidity.The rolling and laying of three covers usually rely on the common front roof structure surface.Due to the coincidence of action trajectory range and operation methods,there are problems that interfere with each other and lead to the low degree of automation in the actual production.It is also not conducive to the systematic and intelligent control of CSGs.According to the functional requirements of the three covers,a coordinative operation device was designed.The main research content included two hardware parts(the outer operation structure and the inner operation structure)and their coordinated control method.The specific corresponding transmission structure and the position detection method of covers were emphasized.The key points of this research were verified by experiments of the scaled model and field CSG.The experiments result of the scaled model showed that the mean relative error(MRE)of different opening values of three covers was less than 3.5%,the root mean square error(RMSE)was less than 2.0%.The value of coefficient of variation(CV)of the device was less than 3.0%at each opening point.The outer operation structure also showed good control accuracy and stability in the field experiments,the MRE was less than 2.5%,RMSE was less than 1.26%,and the CV was less than 1.0%.The overall measured experiment results of the scaled model and field CSG showed similar changing trends,which verified the model experiment results and the implementation feasibility of the overall designed device.The research provided a theoretical basis and systematic technical support for the operation of three covers,which was of great practical significance to the automation and intelligent development of the CSG.