WorldWide Drilling Resource

Make It Intuitive by Britt Storkson Owner, P2FlowLLC There is much to be said for familiarity - being comfortable with people, places, and things where you work and play. A similar concept when it comes to building and operating computers and machinery, a good design practice is to make the control systems “intuitive”. Wikipedia defines intuitive (intuition) as: “The ability to acquire knowledge without proof, evidence, or conscious reasoning, or without understand- ing how the knowledge was acquired.” One could say intuition requires little in the way of the thought process to perform successfully. Often, this reduction of in- tellectual engagement is the result of past experience with similar equipment or processes. We can cite many examples of in- tuitive operations or processes, as they are everywhere. Take the average machine screw for example. We all know it’s “righty tighty” and “lefty loosey”. Of course there are exceptions with left-hand threads for specific applications, but those are the ex- ceptions and most people are aware of it. The idea here is, most of us, when using a machine screw, automatically know the screw needs to turn clockwise if we want to tighten it and counterclockwise if we want to loosen it. This does not need to be learned over and over again. Often, other functions are standardized, such as the gear selector on an automatic transmission. Standardization allows people to drive different cars without having to relearn automatic transmission gear positions for each car. This has safety implications because one may intend to put the transmission in one gear, but unintentionally put it in another gear - which could cause an accident. Lack of intuitive control systems is not only an inconvenience, but has been cited in accident reports a number of times over the years. In 2014, Asiana Flight 214 flew in too low and too slow to the San Francisco airport and hit the seawall, resulting in three deaths and a number of injuries. According to news reports, an overreliance on automated cockpit systems has figured in dozens of air crashes and incidents in recent years. While overreliance is certainly a factor in a number of crashes, coun- terintuitive control systems can exacerbate the problem even further. John Cox, an aviation safety consultant, was quoted during the investigation as saying: “Some people, if they believe the autothrottles are engaged, and if they are used to flying with the autothrottle engaged, will not realize that the autothrottles are not engaged and will let the plane get pretty slow. That has come up before.” His point is, whether the autothrottles are or are not engaged is not clearly obvious or intuitive, resulting in confusion and leading to errors. When making control systems it is important to make all functions consistent and clearly obvious to the user. We automat- ically associate a red light with an alarm or stop condition. What if someone used a purple light instead? What if a control systems manufacturer made a machine that turns on a purple light to warn of a problem condition? At best, there would be confusion because we are all used to red lights being a problem condition and a green light being a good condition. This is not intuitive and should be avoided for this reason alone. In my opinion, computer touch screens can present a problem with regards to intuitive operation because there is no “tactile” feedback to the user. Tactile means having to do with the sense of touch; and if one touches the screen, one should have some sort of feedback mechanism to verify to the user the command was received. For most applications, I prefer to use high-quality mechanical switches which provide not only tactile feedback, but also audible (a click when pressed), as well as a visual, feedback on the display to confirm to the user the switch was pressed. This visual feedback can be a numerical value increasing or decreasing, or some- thing on the display changing in some manner to indicate to the user the switch has been pressed. While customers do not typically comment specifically about how great these features are, they are pleased they do not have to consciously think about pressing the correct switch to do what they intend to do in terms of programming the control unit. It’s very intuitive because they don’t have to think much about it to get it right, and this is a good thing. So while intuitive control programming concepts are difficult to quantify, cus- tomers know good programming practices when they see them because they make the system a pleasure to work with instead of a problem to work with. Britt Britt Storkson may be contacted via e-mail to michele@worldwidedrillingresource.com 12 JULY 2018 WorldWide Drilling Resource ®