Veldscholte Lars B, de Beer Sissi
Sustainable Polymer Chemistry Group, Department of Molecules & Materials MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands.
HardwareX. 2022 Mar 9;11:e00288. doi: 10.1016/j.ohx.2022.e00288. eCollection 2022 Apr.
Humidity control is a crucial element for a wide variety of experiments. Yet, often naive methods are used that do not yield stable regulation of the humidity, are slow, or are inflexible. PID-based electropneumatic humidistats solve these problems, but commercial devices are not widespread, typically proprietary and/or prohibitively expensive. Here we describe OpenHumidistat: a free and open-source humidistat for laboratory-scale humidity control that is affordable (€500) and easy to build. The design is based around mixing a humid and dry air flow in varying proportions, using proportional solenoid valves and flow sensors to control flow rates. The mixed flow is led into a measurement chamber, which contains a humidity sensor to provide feedback to the controller, to achieve closed-loop humidity control.
湿度控制对于各种各样的实验来说都是一个关键因素。然而，人们常常使用一些简单的方法，这些方法无法实现对湿度的稳定调节，速度缓慢，或者缺乏灵活性。基于PID的电动气动湿度调节器解决了这些问题，但商业设备并不普及，通常是专有的，而且价格高得令人望而却步。在此，我们介绍OpenHumidistat：一种用于实验室规模湿度控制的免费开源湿度调节器，价格实惠（500欧元）且易于制造。其设计基于以不同比例混合潮湿和干燥的气流，使用比例电磁阀和流量传感器来控制流速。混合气流被引入一个测量室，该测量室包含一个湿度传感器，用于向控制器提供反馈，以实现闭环湿度控制。
