Washing machine: bad communication between user and system. The position of the controls on the keyboard is not logical; the hand has to move from one extreme to another of the surface. Changing the cycle the washing machine automatically resets the spin. Gulf of Execution. Gulf of Evaluation.

1. HUMAN-COMPUTER INTERACTION
Massimo N. Marrazzo - 2017Washing machine
Gulf of Evaluation:
How do I know what happened?
What does it mean?
Have I accomplished my goal?
Bad communication between user and system.
Gulf of Execution:
How do I know what I can do?
What actions are allowed by the system?
How do I do it?
1
What is wrong?
The terms 'Gulfs of Evaluation and Execution' were introduced in Norman (1986) (The Design of Everyday Things)

2. 2
This washing machine has a single knob.
It would seem easier to use but in fact this is more complicated.
Instead of having a washing cycle for each type of tissue and a selector for the temperature,
you can see there is a duplicate of the same cycle, but with different preset temperature values.
The temperature can not be selected outside the values determined by the designer.
To start the machine you have to respect the numbers on my labels because if you set up before
the spin and then the cycle, the washing machine automatically resets the spin according to the
value determined by the designer (default 1000 rpm).
The correct numerical sequence is: 1cycle - 2centrifuge - 3rapid - 4start.
You can not do 2 - 3 - 1 - 4 or 3 - 2 - 1 - 4;
because when you change the cycle (1) it resets the other parameters (2 and 3).
The position of controls on the keyboard, for the correct start sequence (1-2-3-4) is not logic:
the hand have to move from from one extreme to another of the surface, risking to forget a
step, such as to set the 3 (rapid) to reduce by half the time of washing and use less energy.
The position of the controls on the keyboard is not logical; the hand
has to move from one extreme to another of the surface.
Changing the cycle the washing machine automatically resets the spin.
HUMAN-COMPUTER INTERACTION
Massimo N. Marrazzo - 2017Washing machine
What is wrong?

3. grooves/countersinks
HUMAN-COMPUTER INTERACTION
Washing machine
3
Examples of control panel that work better
In this model the improvement of reading the
program numbers is accomplished by
grooves/countersinks
linear flow of choice
Set Cycle / set Temperature / set Spin speed / Start
Suggestion
Massimo N. Marrazzo - 2017

4. Set Cycle / set Temperature / set Spin speed / Start
4
HUMAN-COMPUTER INTERACTION
Washing machine
redesign interface so you have a linear flow of choice
mechanical or LED buttons: evident state for other parameters
rotary knobs with timer or LED display: show time progression of the washing cycle
linear flow of choice
Suggestions:
Examples of control panel that work better
Suggestion
Massimo N. Marrazzo - 2017