Articles about PID control and loop tuning fundamentals, tablet-based augmented reality, high-performance HMIs, selecting flowmeters for natural gas, and improving flowmeter calibration were Control Engineering’s five most clicked articles from August 8-14. Miss something? You can catch up here.

The top 5 most read articles online, from Aug. 8-14 for Control Engineering, covered PID control and loop tuning fundamentals, tablet-based augmented reality, high-performance HMIs, selecting flowmeters for natural gas, and improving flowmeter calibration.
1. Understanding PID control and loop tuning fundamentals
PID loop tuning may not be a hard science, but it’s not magic either. Here are some tuning tips that work.
2. Tablet-based augmented reality helps predictive maintenance for pumps
Video: sensors on critical pumps can feed a system to help technicians or operators identify when failures are pending and improve energy efficiency. A major U.S. refinery will host a pilot pump diagnostic project, similar to an NIWeek 2016 stage demonstration held on Aug. 2.
3. Developing high-performance HMIs: Enhancing interface effectiveness
This two-part series examines the development of high-performance, human-machine interface (HMI) methodology. Part 2 focuses on accuracy versus context, accessibility, visual hierarchy, animation versus static indication, and 2-D versus 3-D screens.
4. Selecting flowmeters for natural gas
Different parts of the natural gas delivery chain require different instruments, such as differential pressure (DP), ultrasonic, and Coriolis flowmeters.
5. Improving flowmeter calibration
Instrumentation engineers should understand the common methods used in measuring viscosity and their effects on final flowmeter calibration data.
The list was developed using CFE Media’s web analytics for stories viewed on controleng.com, August 8-14, for articles published within the last two months.
Chris Vavra, production editor, CFE Media, [email protected].