In this paper, we investigated a pyramidal hopper with extended discharge at the exit to make a bag of particles to a designated weight. Any feedback control strategy cannot be applied because the exit gate does not have any encoders to check its size, the gate size cannot be adjusted precisely during the closing motion, and the speed of the closing gate is relatively slow compared to the discharge rate of the particles. By only processing the weighing scale measurement in real time, we need to find the best point of time to start the exit gate closure of the pyramidal hopper to fill precise amount of particles into the bag. We developed and compared two control methods to determine appropriate point to initiate gate closure. First, we developed a control method by applying an empirical model describing the correlation between the gate size and the particle discharge rate, which is established by thorough experiments. Second, we developed a control method using curve fitting to predict the discharge rate of particles during gate closing motion without experiment. Both control methods were demonstrated using real time experiments, and the first one with an empirical model showed better result for final weight. This method can be directly applied to weight control of bag filling hopper without modifying the hardware system.

中文翻译：

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锥体料斗出口门的颗粒排放率分析及控制规律

在本文中，我们研究了一种锥形料斗，在出口处延长排放，以制造一袋指定重量的颗粒。无法应用任何反馈控制策略，因为出口门没有任何编码器来检查其大小，在关闭运动过程中无法精确调整门大小，并且关闭门的速度与出口速度相比相对较慢粒子。通过仅实时处理称重测量，我们需要找到最佳时间点开始关闭锥形料斗的出口门，以将精确数量的颗粒填充到袋子中。我们开发并比较了两种控制方法，以确定启动闸门关闭的适当点。第一的，我们通过应用经验模型开发了一种控制方法，该模型描述了浇口尺寸和颗粒排放速率之间的相关性，这是通过彻底的实验建立的。其次，我们开发了一种使用曲线拟合的控制方法，无需实验即可预测门关闭运动期间颗粒的排放速率。两种控制方法都使用实时实验进行了演示，第一个带有经验模型的控制方法显示出更好的最终重量结果。该方法可直接应用于袋装料斗的重量控制，无需修改硬件系统。两种控制方法都使用实时实验进行了演示，第一个带有经验模型的控制方法显示出更好的最终重量结果。该方法可直接应用于袋装料斗的重量控制，无需修改硬件系统。两种控制方法都使用实时实验进行了演示，第一个带有经验模型的控制方法显示出更好的最终重量结果。该方法可直接应用于袋装料斗的重量控制，无需修改硬件系统。