Put the H in HMI

Or maybe just incomplete.

I manufacture an emissions control system that is used on the generators of very large yachts. The control interface is a touch screen (6" X 3.5") HMI with a home screen that displays two guages, temperature and pressure in good old fashioned analog steam gauge form. In the lower center of each gauge is a box that displays the numerical reading.

The setpoint display is also a button that when pressed brings up a setpoint entry box on top of the active display. the new setpoint is entered keypad style, hit enter, and the box goes away. It is simple, uncluttered, does not require sliding a finger or stylus on a tiny and hard to manage input. The system is built for engineers who need information and a degree of control, not for IT folks or computer nerds.

There is room on the screen off to one side to present switch box to select auto or manual operation, another to display a setpoint, and another to display operating hours. There is a “button” to select a history page that when selected will change the page to a log file of operating parameters logged each minute of operation. Complete logs are also recorded on a removable USB drive for analytic purposes. The HMI has the capability to connect to the vessel network for remote monitoring of alarms, display, and control though most users do not use this feature.

It is not difficult to design a useful HMI that provides the user with all the information required without overload or increasing the workload. Different levels of users have different access levels. The watchstander gets what he needs and is not swamped with too much information yet a great deal of information is available to those who need it and can use it.

That is my philosophy when designing the human machine interface. But then I am a grumpy old steam engineer.

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Just Googled “nasa cockpit design human interface”

This is the first hit:

Fire_Hose

That is a 20 year old document that might just as well talk about what makes the best tool for making cave drawings.

Modern Flight Management Systems have relegated most of those issues to papyrus scrolls.

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This is so true and yet my experience would be your system is far above average. With reference to say a chiller or purifier they are going to offer you the off the shelf set up. Sometimes they are unwilling to change it even at the cost of a change order. They seem to be improving slightly lately.

I’m sure your success is not based on old, grumpy or steam but on a deep understanding of the fundamentals of the process you are trying to control AND knowledge of what an operator needs to do so.

Thank you for the compliments! My customers have never complained about too much information but often ask for more and sometimes it is hard to resist adding “features” that in my experience more often create more issues than they resolve.

As the system designer (the whole system, not just the interface) I am hungry for data … I can’t get enough but imposing my personal hunger for minutiae on a user who already has more on his plate than he could ever swallow is, in my opinion, counter productive.

Yes, I missed that it was that old. I was looking more at the H side of the HMI.

IIRC the situation on the McCain was with regards to the throttle. Helmsman was trying to shift control of throttle to a different station while keeping the helm. However there was a training shortfall and it wasn’t done properly.

The older design aircraft is much more complex but there was a long and steep learning curve needed to overcome bad design.

I would say they were less complex but more complicated to operate. That is why the first few generations of airliners required a flight engineer, the complication of managing what is today a far less complex system was beyond the saturation point of a pair of humans.

We increase complexity in order to reduce the complications of its operation. Automate what we don’t have the capacity to see, understand, and respond and make as much as possible invisible until or unless it becomes important to the task and at that point decide how much priority to assign that task.

The most critical task in airplane driving is “fly the airplane” … as long as you can do that you will have time to look at the other stuff. The object of a good system is to allow the operator to operate it or secure it without being drowned in a flood of useless bling.

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Yes more complicated to operate is a better way to put it. The comparison I was thinking about was the aircraft cockpit compared to the bridge of the McCain.

I have been fortunate to have launched and tested DDG’ 51 through 112 and DDG1000 and a bunch of figs and cruisers. These include Fitzgerald and McCain.
I have watched the Navy complicate the simple. Only a couple of times did they listen. Mostly they called me a dinosaur,KP 58.
When touch screens came to the bridge, I was totally against them and told them why and I told them to remember I told them so. It has taken way to long to listen.
If you step onto the bridge of these ships and see all the glass displays and wonder what is going to happen when the bullets start flying through that glass? Bye bye touch screens, menus and led’s. You will appreciate the feel of mechanical controls and valves that can be opened or closed by hand.

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It is a bit retrograde to replace touch screens with pneumatic and telemotor systems that are no less subject to damage just because they feel better to operate.

I think the issue is that the glass bridge has more design input from computer nerds than deckhands and mates and judging by recent incidents, have never been “stress tested.”

The deckhand and mate are as much a part of the system as the gee whiz panels but are certainly less dependable than the electronics. The only element missing that was capable of safe and dependable operation was the human one.

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I agree. If you get into design at all, even at the hobby level it quickly becomes apparent that trade-offs are involved.

In the case of the McCain; if too much stress is put on the system, increased tempo and decreased training for example, something is going to break.

It’s natural for the blame to focus at the tip of the spear because people tend to blame the person and thing closest in distance and in time to the incident.

EDIT: The touch screen may in fact not be the best solution for the throttle controls in this case. Just saying some other solution is going to be a comprise as well.

It would be interesting to hear from people who have actually used pre- and post- touch screen systems if they felt that anything was lost from being denied audible and tactile feedback from some controls. I know that drillers have spoken of the loss in their case.

Cheers,

Earl

On the same google search as before but filter for time:

It’s been mentioned on the forum before about the old gyro compass repeaters clicking off (IIRC it was 6 times per degree) during turns. It was helpful for judging rate of turn (ROT).

I was wondering why this was considered better than looking at a display. Is it just having to be in a specific spot to read a display or is it because the audio information used a different channel to the brain so to speak than did the visual info?

Or that a changing rate would be apparent without having to check?

In a highly dynamic environment it may become difficult to convert data to information quickly enough to manage several processes.

A great example is while flying a sailplane. When thermalling (remaining in the cone of rising air created by a hot spot on the ground) the pilot is watching bank angle, air speed, rate of turn and ascent or descent all the while dealing with some degree of turbulence. It can be a lot to juggle.

Instead of having to visually read an instrument on the panel to determine rate of climb or descent, a very sensitive instrument called a variometer is fitted on a sailplane panel. It displays rate just like the standard rate of climb but the modern version also sounds a tone, rising in pitch with climb and lowering when descending. The pilot doesn’t have to look at a display and that frees up a lot of brain space to deal with other inputs. The audio input reduces task saturation.

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On one ship I was master of the bow thruster was controlled by push buttons. Three speeds either way and off. In bright sunshine it was difficult to see which button was illuminated and I would have found a lever that I could sense where it was while looking where I wanted to look to be better. The vessel was a 400 teu container vessel and during berthing or leaving I was the only person on the bridge using the bridge wing engine controls, tiller and bow thruster plus UHF radio.
The helmsman and watch officer joined me as soon as they could.

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It seems to me that tasks like this differ.

Take a task like; say for example landing a small twin-screw vessel in unfavorable conditions. It is similar to something like down hill skiing, it takes skill and practice but it’s not really a situation where information overload would take place.

By contrast as you say keeping track of engine order, wheel position, bow thruster, tugs, lines etc it’s possible to temporally lose track of some vital part of the situation.

This, for example doesn’t strike me as a situation where information overload is an issue. It’s just a skill thing.

It might feel very intense at the time but there would be tight focus on only a few items that required attention.

touch screens are nice for some stuff but you get the double touch of your finger and operators learn finger touch combos by heart and not reading the display.
Using a mouse makes for much more deliberate decision as its slower.
I can think of the security push code to my office, I have forgotten the code but I know the combo to push.
Thats like displays, humans recognize everything except numbers so a dial with needles give an instant recognition by a human but not a number that your brain has to interpret as normal.
We remember where the gauge needle should be.

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what happens when water knee deep rolls thru the bridge? what happens when the battle ship gets straffed and a bullet hits this touch screen? … or shrapnel from a nearby hit blows the glass out along with the screen? doesn’t sound very survivable to me for a ship of the line!!

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Ulstein Bridge Vision has been around for a while: