Design and test on real-time measurement system of mat roller workload for sunlight greenhouse

Abstract: In the paper, a study was conducted on the workload change of a mat rolling machine, which belongs to the agricultural machinery research of a sunlight greenhouse. The specific content is the on-line measurement for the mat roller workload on the foundation of the summarization of current related research. To be exact, first, the paper analyzes the working conditions and operating feature of the mat roller. Then, choosing a dynamic torque sensor of the strain gauge type, the real-time load measurement system was designed and developed on the LabVIEW platform, with the application of VI (virtual instrument) technology. Finally, the on-line test system for mat roller workload was launched and completed, whose main hardware was composed of the sensor and the signal amplifier, the data acquisition card, the electrical control system for mat roller, the stroke limiter, and the accessory device for sensor installation, etc. Additionally, its staple software function consisted of acquiring data, processing data, saving data, and automatically controlling the mat roller.Generally, the rollers can be divided into the reel-type and the rope-type in light of its working principle. We choose the side mat roller with a reel pushing up covering and the rear mat roller with a rope pulling up covering as subjects. Therefore, for one thing, aiming at the reel-type, load change was measured out when employing heat-insulating coverings of two materials and three lengths. For another, aiming at the rope-type, load change was measured out when utilizing heat-insulating coverings of three materials and two conditions (dryness and wetness).Specifically, in the beginning, prior to have the workload test, the sensor was calibrated, together with systematically testing the system. Next, during the test, according to the different rolling machines, diverse sunlight greenhouses were selected while with the same type of roller was utilized. Secondly, regarding test data collection, after configuring a collected sample of 1,000 and a sampling frequency of 10,000 S/s, the mean value was acquired as the instant load at the moment by means of using the LabVIEW statistical module to count and analyze the sample. Thirdly, the roller ran continuously, thereby gathering the data that represented the load variation. Eventually, when the test was complete, the acquired data was disposed and analyzed with Excel spreadsheet software. The test, measuring the instant loads of a reel-type roller and a rope-type roller respectively, is the initial study on the real-time measurement for roller workload, whose entire data error does not exceed ±6N.m. The results of the test showed that first, the mat roller with a reel pushing up acquires the maximum working load at the top of the sunlight greenhouse while the rear mat roller with a rope pulling up receives the maximum working load in an uncertain position. Secondly, the working load of the rope-type, whose change curve is more modest, is far less than that of the reel-type. Additionally, the rope-type mat roller, currently used in the production, has an overlarge maximum load. Finally, the study was initially focused on actually measuring the workload of the mat roller, thereby having some deficiencies. And there are three suggestions that can be carried out on deepening the research, including increasing the length of heat-insulating coverings, analyzing the relationship between the front roof slope of the sunlight greenhouse and the workload of the mat roller, and actually measuring the workload variation curves of the front mat roller with a reel pushing up covering.