Take the 2-minute tour ×
Electrical Engineering Stack Exchange is a question and answer site for electronics and electrical engineering professionals, students, and enthusiasts. It's 100% free, no registration required.

Dyson keep going on about their new "digital" motor. What is a digital motor? How can a motor be digital, it is inherently analog? Is it just marketing doublespeak?

share|improve this question
1  
Could it be a stepper motor in disguise? :p –  sybreon Apr 15 '11 at 1:11
7  
It could be a motor that is on or off :L –  Dean Apr 15 '11 at 8:51
16  
You push it around with a finger! –  Pete Kirkham Apr 15 '11 at 17:30
1  
@ThomasO, you need to provide links to information like this. –  Kortuk Apr 15 '11 at 20:40
4  
@Dean, People easily found the information, so I assume it was easy to come by, but when you want to discuss someone's claims it helps if you link directly to their claims. This will improve the quality of the site directly. Directly quoting the claims with links will provide best results. This way in 20 years people can still understand the context. –  Kortuk Apr 16 '11 at 13:27
show 3 more comments

6 Answers 6

Unfortunately the term digital seems to be applied inappropriately to all sorts of things.

Here is a good video from the EEV blog taking Dyson to task for their "Dyson digital motor".

Here is Dyson's take where they say "Dyson digital motors use digital pulse technology, spinning at up to 104,000 times a minute"

Then again most switched to turn a motor on or off are digital, binary in fact ;-)

share|improve this answer
    
So basically it's a standard brushless motor? Why do they say it uses an iron core? I thought you needed a magnetic core for high power applications. –  Faken Apr 15 '11 at 4:37
11  
"And as the carbon brushes wear down, they emit carbon particles, which is bad for the environment." What a bunch of nonsense. –  endolith Apr 15 '11 at 16:06
7  
That EEV blog is hilarious! –  BG100 Apr 15 '11 at 17:51
1  
@Majenko, Use the vacuum and you will change your tone. Helluva great vacuum, I could care less about their marketing, my carpet is clean : ) –  Kortuk Nov 13 '11 at 5:05
1  
Our intelligence has been severely damaged, at times, by the likes of marketing schemes the world over. –  JYelton Dec 11 '12 at 17:07
show 4 more comments

Turning something on and off does not make it "digital". Switch-mode power supplies are not digital. Class D amplifiers are not digital. Just because something outputs square waves doesn't mean it's digital.

"Digital" means data or information being transferred in the form of discrete symbols. As long as a symbol is received without error, the signal suffers zero degradation, unlike analog which is incrementally corrupted by noise and distortion.

Those symbols can be represented by on and off pulses, like in digital logic, but also by any other scheme you can think of, like phase shifts of a sine wave, or by frequency shifts of a sine wave, or whatever. They're all digital.

share|improve this answer
3  
Be careful here, remember that Morse code is digital. Not all digital codes contain error correction or check bits, so just because it is digital does not guarantee perfect reception. –  JonnyBoats Apr 16 '11 at 2:09
1  
I didn't mean that it guarantees perfect reception. I mean that, if there are no errors, the signal is transmitted with zero degradation. If you transmit it through the same channel many times it will not degrade, while analog will, even if the noise floor is very low. –  endolith Apr 16 '11 at 4:04
3  
As an audio guy I've had the Class D is not digital argument far too many times. I keep feeling the entire thing may have been avoided if they simply skipped 'D' in topology naming... –  Mark Jun 21 '11 at 22:29
    
@Mark: Yeah, or just call it a "PWM amplifier". I guess PDM amplifier or other modulations schemes would also be considered Class D? –  endolith Jun 22 '11 at 17:26
1  
Things like like PWM and FM can be analog or digital, depending upon what's generating or receiving the signal (in particular, whether the receiver will "care" about details finer than the resolution of the channel). My point was that the time and voltage domains can independently be continuous or discrete; making one or the other discrete can offer considerable advantages even if the other is continuous. In a true digital signal, both time and voltage are generally discrete (though the sampling rate and number of levels may be large relative to the semantic content). –  supercat Nov 14 '11 at 17:00
show 4 more comments

Agreed, it's all marketing. I do a lot of work with ac motors, all the stuff they talk about on the website is comical. The motor itself is not digital, the power regulator to the motor is, but who cares. It's a vacuum, not exactly a precision machine. As far as the materials, they probably just lower the over all weight (the motor is probably the single most heaviest part) to reduce shipping cost. And one last thing, carbon dust isn't going to hurt the environment.

share|improve this answer
add comment

They could be referring to the control method as well. Most motors are controlled with PWM from an external source, but if there's a built-in driver then you might command it with serial protocols or DIO instead of voltage. I've seen 'smart motors' like that. It looks like there's electronics integrated on to the Dyson motor, so that might be it.

But yeah, marketspeak.

share|improve this answer
add comment

Here's a counterpoint view:

The vacuum cleaner motor in question will either work or go kaput. That sounds legitimately digital... to the marketing folks, at least!

Then again, that's more of a Binary Motor. Did I just give the marketing team a big "O"?

share|improve this answer
add comment

According to this article stepper motors are sometimes called digital motors because they are driven with pulses which control the degree of rotation.

I'm sure Dyson choose to call the motor a digital motor in their marketing because it sounds more sciency, and that seems to be a bit of a trend these days... at least they don't say it will give your carpet up to 90% more shine.

share|improve this answer
2  
It would need nutritive fruit micro-oils and a good dose of Nutri-ceramides to do that! –  shuckc Oct 19 '12 at 15:48
add comment

protected by Community Jan 23 '12 at 6:08

Thank you for your interest in this question. Because it has attracted low-quality answers, posting an answer now requires 10 reputation on this site.

Would you like to answer one of these unanswered questions instead?

Not the answer you're looking for? Browse other questions tagged or ask your own question.