Bad Ergonomics: Press GO to STOP

Bad Ergonomics: Press GO to STOP
[人因工程 ]
(2003/02/20)

Bad Ergonomics: Press GO to STOP

This example is taken from a European project called SAVE. Imagine that you drive a car that can take over control in case of an emergency, e.g., a cardiac arrest. To be sure, the system asks whether it should take over control, but it does so in a complex way.

Apart from being hardly audible, the text is difficult to understand. Literally the metallic voice says:

“It is supposed that you have severe problems to drive. If you do not want an activation of the autopilot, press the Confirm button.”

Naturally a “Cancel” button should have been used, because that is what happens if the button is pressed: the action is cancelled.

Actually, I must say that the SAVE project is not bad at all. I worked on it, so how can I say bad things about it? But errors are made everywhere. I also believe that in the end this text was changed.

Editor’s Comments:

The editor has cited numerous examples demonstrating why the term “ergonomic” must not be equated with “form-fitting” or “tactile”. To do so debases the term. The sense of touch is one of the factors in Human Factors Design, but hardly the only factor, and often not the primary factor. The sense of sight is usually the first sense engaged in any Man Machine Interface, and as this example demonstrates, hearing runs a close second.

Let me be clear. The designers’ less than perfect English grammar is not the problem. We are addressing design, and ergonomic defects transcend language. The problem is a failure to appreciate the life or death importance of clarity to industrial design.

The sentence “It is supposed that you have severe problems to drive”, while awkward in its construction, is nevertheless understandable. This is not the problem. The problem is the second sentence, “If you do not want an activation of the autopilot, press the Confirm button.”

Consider the way the choice is put to the user. “If you do not want an activation of the autopilot, press the Confirm button.” The designer is saying “If you do not want something, confirm that you do not want it.” Only not so clearly.

The product designer is demanding that the driver of a moving vehicle, possibly undergoing cardiac arrest, barreling down a public highway, to clear his head, unravel the designer’s double negatives, then make a decision about whether or not to press a button, a decision which may or may not end his life.

The designer might as well ask the driver to play Russian Roulette with a double-barreled shotgun.

Obviously this has nothing whatsoever to do with foreign language skills, and everything to do with the fact that the product designer was not thinking clearly in any language.

How should the designer have worded the message? How about:

“If you can drive, press OK.”

Wording the instruction in this direct and intuitive fashion is the linguistic equivalent of “natural mapping” in physical space. The positive state “can drive” is mapped to the positive affirmation, “OK”. Positive is mapped to positive, just as when an electrical circuit is turned ON, the power switch reads “ON”. This allows a user to understand his situation and react spontaneously, without hesitation or delay.

Other possibilities come to mind. The exact wording is not critical as long as the meaning is clear. The bottom line, as always, is “KISS”. For those unfamiliar with the expression, it means “Keep It Simple, Stupid!”

— Bevin Chu

Explanation: Bad Ergonomics: Press GO to STOP
Illustration: None
Author: Dick de Waard
Affiliation: Human Factors and Ergonomics Society Europe Chapter
Source: http://utopia.ision.nl/users/hfesec/index.htm
Publication Date: 1998-1999
Original Language: English
Editor: Bevin Chu, Registered Architect

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Nonergonomic! Long Live Analog!

Nonergonomic! Long Live Analog!
[人因工程 ]
(2003/02/20)


Long Live Analog!

The author/editor likes living in the Digital Age. On the whole, I prefer digital technology over older analog technology. I definitely prefer smaller, lighter, more durable DVDs to bulkier, heavier, easily damaged VHS video tapes. I even prefer audio CDs, warts and all, to easily scratched vinyl LPs. Audiophiles should admit that the problem with “gritty” or “harsh” sounding audio CDs is not that the music has been digitized, but that the digital “bits” are too coarse, because the recording industry set the bar too low when they established industry standards for the compact disc.

Digital data displays however, are another story altogether. For many purposes, analog dials are vastly superior to digital data displays. The reason should be obvious. Traditional circular analog dials communicate far more useful and important information than modern digital data displays consisting of a horizontal row of arabic numerals.

Many engineers and designers assume that the function of a clock or a speedometer is to provide the user with the time of day or the speed of the vehicle, and nothing more. They assume this bottom line data is all the information available and all the information worth communicating.

They could not be more mistaken. The traditional analog speedometer dial in the accompanying illustration doesn’t merely inform the driver that he is standing still at the moment, it provides the driver with all sorts of additional, valuable information. Even with the engine turned off and the handbrake pulled, the traditional analog speedometer speaks to us, revealing the vehicle’s theoretical maximum speed.

The general position of the needle on a large circular analog dial can easily be determined out of one’s peripheral vision. Once a vehicle is in motion, the position of the speedometer needle along a 270 degree arc instantly informs a driver where his speed falls within the vehicle’s “performance envelope”. A race or rally driver can continuously refer to his analog speedometer and tachometer to time his gear changes, without ever taking his eyes off the twisting road ahead. Try that with a digital data display! Even the movement of the speedometer needle as it alternately swings clockwise and counterclockwise constantly updates a driver about his rate of acceleration and deceleration.

Now turn to the illustration of the digital speedometer. Contrast the poverty of information provided by a conventional numeric digital display. No comparison is possible.

Note: The terms “analog” and “digital” in this context refer only to how instruments display data, not how they process it. Therefore a PC clock that displays an old-fashioned circular clock face featuring hour, minute and second hands on a LCD monitor would be defined as “analog”.

— Bevin Chu

Explanation: Long Live Analog!
Illustration: Nonergonomic! Long Live Analog!
Author: Bevin Chu
Affiliation: CETRA Design Information Section
Source: http://www.philly.com/mld/philly/business/4814052.htm
Publication Date: 2003
Original Language: English
Editor: Bevin Chu, Registered Architect

Bad Ergonomics: The (In)Famous Palm Beach County Ballot

Bad Ergonomics: The (In)Famous Palm Beach County Ballot
[人因工程 ]
(2003/02/18)

Bad Ergonomics: The (In)Famous Palm Beach County Ballot

Submitted by Heino Widdel

Editor’s Comments:

More proof that the term “ergonomic” must not be equated merely with design that is friendly to the touch. Far more is involved, in particular the sense of sight. Ergonomics is important. Unfortunately the general public seldom pays any attention to ergonomics until problems such as this create utter chaos. The Florida ballot fiasco was an object lesson in the importance of ergonomic design that should not be forgotten simply because election fever has passed.

— Bevin Chu

Explanation: Bad Ergonomics: The (In)Famous Palm Beach County Ballot
Illustration: The (In)Famous Palm Beach County Ballot
Author: Heino Widdel
Affiliation: Human Factors and Ergonomics Society Europe Chapter
Source: http://utopia.ision.nl/users/hfesec/index.htm
Publication Date: 1998-1999
Original Language: English
Editor: Bevin Chu, Registered Architect

Bad Ergonomics: Keep Right

Bad Ergonomics: Keep Right
[人因工程 ]
(2003/02/17)

Bad Ergonomics: Keep Right

Thanks to John Rietveld, who has a large set of signs and signals on his homepage

http://signalfan.com/

Editor’s Comments:

Normally this editor cannot resist the urge to editorialize at great length about the fundamental principles of bad ergonomics, but this sign has says it all!

— Bevin Chu

Explanation: Bad Ergonomics: Right?
Illustration: Keep Right
Author: John Rietveld
Affiliation: Human Factors and Ergonomics Society Europe Chapter
Source: http://utopia.ision.nl/users/hfesec/index.htm
Publication Date: 1998-1999
Original Language: English
Editor: Bevin Chu, Registered Architect

Bad Ergonomics: Tonearm Control Lever

Bad Ergonomics: Tonearm Control Lever
[人因工程 ]
(2003/02/13)

Bad Ergonomics: Tonearm Control Lever

When the user of this poorly designed turntable lowers the tonearm control lever, tilting it down toward himself, the tonearm does exactly the opposite of what he has a right to expect, it rises up off the surface of the record!

Editor’s Comments:

I have no doubt that the designer of this turntable was earnestly attempting to solve a difficult mechanical engineering problem to the best of his ability, and not indulging in mere product styling. I am sure he worked late into the night working out the complex geometry of the control lever linkage to the tonearm. Unfortunately he neglected the most important consideration of all. Mechanical engineering solutions are meant to be used by human beings, and human beings use mechanical devices certain ways and not others based on long experience with the world around them. It is not reasonable to expect human users to abruptly forsake these hard-won and usually correct instincts. Rather it is the responsibility of architects, urban planners, interior designers, and industrial designers to make sure the man-made environment conforms to the requirements of human physiology and psychology.

— Bevin Chu

Explanation: Bad Ergonomics: Tonearm Control Lever
Illustration: Tonearm Control Lever
Author: Niels Taatgen
Affiliation: Human Factors and Ergonomics Society Europe Chapter
Source: http://utopia.ision.nl/users/hfesec/index.htm
Publication Date: 1998-1999
Original Language: English
Editor: Bevin Chu, Registered Architect

Bad Ergonomics: The Double Negative

Bad Ergonomics: The Double Negative
[人因工程 ]
(2003/02/13)

Bad Ergonomics: The Double Negative

In Czech ‘Bez poplatku’ means ‘without toll’. The above sign indicates a toll road.

Editor’s Comments:

If you were seeking proof that “ergonomics” is not just about “anatomically correct design”, here it is. The “Man Machine Interface” includes all sorts of ways for humans to interact with human artifacts beyond the tactile. Gripping an automobile steering wheel is one way of interfacing with a machine, but hardly the only way. Merely reading the engine RPMs off an automobile tachometer also qualifies as interfacing with a machine. One need not actually touch a machine to interface with it. Therefore any defect that creates difficulty for users of technology qualifies as bad ergonomics, even a hard to read instrument gauge, even bad grammar on a road sign, such as a double negative.

Fiascoes like this occur when people in positions of authority forfeit their responsibilities. Clearly it was not a matter of cost. The only cost item here was paint for the letters on the sign. The text in the road sign read “Toll Free”. The diagonal red slash painted across the text was some faceless bureaucrat’s way of saying “NOT Toll Free”. Apparently the mental effort needed to pause, clear his mind, and come to the realization the sign ought to simply read “TOLL ROAD” required too much initiative on his part.

— Bevin Chu

Explanation: Bad Ergonomics: The Double Negative
Illustration: The Double Negative
Author: Dick de Waard
Affiliation: Human Factors and Ergonomics Society Europe Chapter
Source: http://utopia.ision.nl/users/hfesec/index.htm
Publication Date: 1998-1999
Original Language: English
Editor: Bevin Chu, Registered Architect

Bad Ergonomics: Stove Controls 2

Bad Ergonomics: Stove Controls 2
[人因工程 ]
(2003/02/13)

Bad Ergonomics: Stove Controls 2

On our holiday in the Alps we found this classical example in our rented house. Apparently they still exist, absolutely no clue is given which knob operates which heater. And only one light indicates that either heater is switched on.

My wife knew that as we read from left to right and from top down, the left hand knob had to operate the top heater, which was correct, but we frequently made a mistake. The best solution is to have the knobs arranged the same way the heaters are, two knobs below each other. If this is not possible for whatever reason, two indicators would be useful:

Although you could add a red surface on the right hand knob as to indicate that this one operates the heater with the red circle, you have to be aware that that circle becomes invisible as soon as you put a pan on it. Therefore, the cheapest solution is an engraved line to the heater.

Editor’s Comments:

This set of stove controls represents essentially the same design problem cited in “Nonergonomic!: City Bus Door Controls”. The problem here, as there, is the failure to clearly “map” control switches to the devices they control, be they bus doors or heating elements. Instead of being arrayed alongside and parallel to the heating elements, the control knobs have been relocated to the end of the stove, perpendicular to the heating elements.

This decision does not appear to have been arbitary. It was probably motivated by an entirely reasonable desire to position the controls close to the front of the kitchen counter. Nevertheless it was a mistake. The predictable result has been the loss of natural mapping, and the introduction of ambiguity, uncertainty and confusion. Imagine the cumulative frustration experienced by everyone who has ever had occasion to use this stove. Now multiply that by the number of units sold. I think you will agree that more alternatives should have been explored.

— Bevin Chu

Explanation: Bad Ergonomics: Stove Controls 2
Illustration: Stove Controls 2
Author: Dick de Waard
Affiliation: Human Factors and Ergonomics Society Europe Chapter
Source: http://utopia.ision.nl/users/hfesec/index.htm
Publication Date: 1998-1999
Original Language: English
Editor: Bevin Chu, Registered Architect