[comp.society.futures] Proper design

engelson-sean@cs.yale.edu (Sean P. Engelson) (05/06/91)

In article <16@nvuxr.UUCP>, ccw@nvuxr.UUCP (christopher wood) writes:
|> In article <1991Apr30.225521.755@husc3.harvard.edu> mason3@husc9.harvard.edu (Richard Mason) writes:
|> 
|> >(And yes, a bug in that automatic system can be fatal: witness
|> >the Audis that unpredictably lunged into first gear and killed people due
|> >to a fault in the cruise control chip).
|> 
|> No faults were ever discovered in the Audis.  This is a popular
|> misconception spread mostly by the media.  The cars lunged forward
|> because drivers stomped on the gas, thinking it was the brake.  I saw
|> the woman on 60 minutes: "I pressed harder and harder on the brake, and
|> the car just kept going faster and faster".  After the accident, no
|> problems were found with either the cruise control or the brake system
|> on that car (or what was left, after it was stopped)
|> 
|> It is tragic that people were injured or killed by these incidents, and
|> it's easy to "blame the engineers" rather than admit that the driver
|> could have possibly made a mistake that had tragic consequences. 
|> Improved driver education is probably the only answer - If your car
|> surges forward, take your feet OFF the pedals.  then find the brake, and
|> stop your car.

But in fact, this too could be due to a design error---one which encourages
the mistaking of the accelerator for the brake.  It is easy to say "well, the 
user should have known what to do; they read the manual, right?"  but this is
not always appropriate.  It is the responsibility of the designers to take
into account the human factors relating to the equipment they build.  It should
always be kept in mind that the machines are there to serve people, and that
if a machine requires the operator to be "redesigned" its time to rethink the
design of the machine.  See _The Psychology of Everyday Things_ by Don Norman
for an excellent explanation of this and other related topics.  Thus, most 
likely, *improved design*, not driver education, is the answer.



-- 
Sean Philip Engelson, Poet Errant	Make your learning a fixture;
Yale Department of Computer Science	Say little and do much;
Box 2158 Yale Station			And receive everyone with 
New Haven, CT 06520			   a friendly attitude.

ccw@nvuxr.UUCP (christopher wood) (05/08/91)

In article <1991May6.131027.2783@cs.yale.edu> engelson-sean@cs.yale.edu (Sean P. Engelson) writes:

>In article <16@nvuxr.UUCP>, ccw@nvuxr.UUCP (christopher wood) writes:
>|> In article <1991Apr30.225521.755@husc3.harvard.edu> mason3@husc9.harvard.edu (Richard Mason) writes:

>|> >(And yes, a bug in that automatic system can be fatal: witness
>|> >the Audis that unpredictably lunged into first gear and killed people due
>|> >to a fault in the cruise control chip).

>|> No faults were ever discovered in the Audis.  This is a popular
>|> misconception spread mostly by the media.  The cars lunged forward
>|> because drivers stomped on the gas, thinking it was the brake.  I saw
>|> the woman on 60 minutes: "I pressed harder and harder on the brake, and
>|> the car just kept going faster and faster". 

[my own comment trimmed]

>|> Improved driver education is probably the only answer - If your car
>|> surges forward, take your feet OFF the pedals.  then find the brake, and
>|> stop your car.

>But in fact, this too could be due to a design error---one which encourages
>the mistaking of the accelerator for the brake.

[trimmed]

>It is the responsibility of the designers to take
>into account the human factors relating to the equipment they build.

[trimmed]
>Thus, it is most
>likely, *improved design*, not driver education, is the answer.

[trimmed]

I am not arguing against ergonomics.  Devices must be usable.  But IN
THIS CASE, I hacve seen nothing to indicate an engineering nor ergonomic
design flaw.  Read the top paragraph I left in - the origional poster
said people were killed (which is true) "due to a bug in the cruise
control chip", which is not!  IN THIS CASE, the designers of an
inherently dangerous piece of machenery (an automobile) were "hung"
because of MEDIA PUBLICITY.

I have seen a study (well, a quick examination of locations of gas and
brake pedals and steering wheels relative to driver's seat center line,
and the force required on the brake and gas pedals).  The Audi was not
extraordinary in any respect.  And drivers in other vehicles have
experienced "unexpected acceleration".

Remember, driving an automobile is something sufficiently tricky and
dantgerous that individuals must be tested and lisenced before they are
allowed to drive at will.

This discussion has wandered off topic.  I'll take a stab at a
conclusion.  Too summarize, good, intuitive design of the human
interface is vital in the design of any object that will be used by
humans.  In spite of this, the user will still make mistakes.  Designers
must make those mistakes as easy as possible to undo.  However,
sometimes, with dangerous devices, it's hard to make everything
undoable.  In these cases, it is imperitive that users be trained to DO
THE RIGHT THING -- recognize those mistakes, then take the appropriate
corrective action.  Occasionally, users who make errors operating
dangerous machinery, will publically blame the engineers.  Once in a
while, the media will smell a good story, and stir up a witch hunt. 
These witch hunts, and the "blame the engineers" attitude, whether
deserved or not, is what was trigerred when Richard Mason repeated the
media-hyped _STROY_ of a bug in the cruise control circuit.

>Sean Philip Engelson, Poet Errant	Make your learning a fixture;


-- 
Chris Wood     Bellcore     ...!bellcore!nvuxr!ccw
                         or ccw@nvuxr.cc.bellcore.com