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In optical experiments, shutters are devices that open or close a path of light. They are often used to limit the duration of light exposure onto a target or onto a detector to reduce possible light-induced damage. Many commercial shutters are available for different applications – some provide very fast opening and closing times, some can handle large optical powers, and others allow for fail-safe operation. Many of these devices are costly and offer limited control options. Here we provide an open-source design for a low-cost, general purpose shutter system based on ubiquitous actuators (servo motors or solenoids) that are connected to an Arduino-based controller. Several shutters can be controlled by one controller, further reducing system cost. The state of the shutters can be controlled via a display built into the controller, by serial commands via USB, or by electrical control lines. The use of a microcontroller makes the shutter controller adaptable – only control options that are used need to be included, and the design accommodates a selection of display and actuator options. We provide designs for all required components, including 3D print files for the actuator holders and cases, the Arduino code, libraries for serial communication (C and python), and example graphical user interfaces for testing.
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A low‐cost modular control system for multistressor experiments
Abstract Marine organisms and ecosystems face multiple, temporally variable stressors in a rapidly changing world. Realistic experiments that incorporate these aspects of physiological stress are important for advancing our ability to understand, predict, and manage their ecological impacts. However, the experimental systems needed to conduct such experiments can be costly. Here, we describe a low‐cost, modular control system that can be used with seawater sensors and actuators to dynamically manipulate multiple seawater variables. It enables researchers to run a variety of realistic multiple‐stressor, variable exposure experiments with a range of marine organisms. This tank controller system is based on the open‐source Arduino prototyping platform and features a custom‐made circuit board with a 16‐bit analog‐to‐digital converter, a real‐time clock, a MicroSD memory card reader, a high‐voltage transistor array, and solderless screw terminal connectors for easy connection of sensors, actuators, and power supplies. The assembly and use of this controller system does not require extensive electronics engineering or programming experience, and each module can be assembled for under 80 USD in parts. To demonstrate the system's capabilities, we present seawater manipulations from experiments involving (1) simultaneous manipulations of dissolved oxygen and pH; (2) fluctuating dissolved oxygen levels; and (3) a controlled stepwise decrease in dissolved oxygen at different temperatures. The low cost and high customizability of this Arduino‐based control system can contribute to expanding capacities for running global change experiments for researchers and students worldwide.
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- PAR ID:
- 10455059
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Limnology and Oceanography: Methods
- Volume:
- 18
- Issue:
- 10
- ISSN:
- 1541-5856
- Page Range / eLocation ID:
- p. 623-634
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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