Mindboards

jojoguy14 wrote:So, basically, what everyone's is saying is that...the touch sensor can NOT be used as a pressure sensor as it is analog?

jojoguy10

P.S. Thanks for the fast responses! I think this made the high score for most posts during a short amount of time!

The NXT touch sensor is not a variable sensor. It is either pressed, or not pressed. The RCX touch sensor IS a variable sensor. It changes values based on the amount of pressure.

nxtreme wrote:

jojoguy14 wrote:the touch sensor can NOT be used as a pressure sensor as it is analog?

Digital, actually. Analog is more like the light sensor.

Actually, a touch sensor IS an analog sensor, even if it only has two states (like the NXT Touch sensor, but NOT like the RCX touch sensor). The light sensor and sound sensor are also analog. Sure, it could also be considered digital (as in boolean), but normally we use the term "digital" to refer to an I2C sensor or UART.

mattallen37 wrote:Actually, a touch sensor IS an analog sensor, even if it only has two states (like the NXT Touch sensor, but NOT like the RCX touch sensor). The light sensor and sound sensor are also analog. Sure, it could also be considered digital (as in boolean), but normally we use the term "digital" to refer to an I2C sensor or UART.

Ok, so we can define it in two ways .

• It's digital because it's either open or closed, i.e. boolean.
  It's analog because it's not digital.

Analog would probably be the more correct term, but digital is more... memorable? for me .

I personally would strictly avoid usinge "digital" referring to touch sensors.

The sensor states of a light or a temperature sensor (configured as analog sensors) are analog, are passed through the 10 bit A/D , and are interpreted as 10 bit numerical values (0...1023).

The sensor state of a touch sensor (configured as an analog sensor) is analog too, is passed through the 10 bit A/D , and is interpreted as a 10 bit numerical value (0...1023).

The sensor state of a touch sensor (configured as a touch sensor) is analog again, is passed through the 10 bit A/D, and is interpreted as a boolean value
(0=FALSE=open= 0 Siemens
vs.
1=TRUE=closed= 0 Ohm ).
There is a threshold in between beyond which the "open" and "closed" states are distinguished from each other (maybe 30 or 50 Ohm or whatever).


Neither of all are digital sensors.

doc-helmut wrote:...Neither of all are digital sensors.

No, but in boolean logic, it could be considered a digital value. Because a 100% ideal switch only has two states, it can be called a digital sensor. It is an accepted term, but I would discourage it's use.

in Boolean algebra I don't recall that I ever had heard or read the term "digital" or "digital value"...
AFAIR there are defined only elements of boolean sets like { 0, 1} or {FALSE, TRUE} (or Power Sets of those sets), equipped with two binary operations called "and" and "or"

Oh fine then, I surrender . I know the correct term isn't digital, it's just an easier way to think of it. Sorry to start a war .

no war, just an explanation.
Correct thinking starts with correct lingustic terms (if you want to read more about it: read Benjamin Lee Whorf: "Language, Thought, and Reality", IIRC)

Ok. And yes, I do agree with you that "Correct thinking starts with correct lingustic terms". Thanks!

Welcome.
Although I must admit that in English my terms are often not that correct :P
(and it's the RING to rule them all...: the Lord of the Rings. But the KING has returned and the Lord of the Rings finally been destroyed.
The trilogy in one line ;) )

doc-helmut wrote:Although I must admit that in English my terms are often not that correct
(and it's the RING to rule them all...: the Lord of the Rings. But the KING has returned and the Lord of the Rings finally been destroyed.
The trilogy in one line )

Well, the best forum is the one that has a big mix of all people from all places! I know it's the Ring, and I'm not talking about Aragorn when I mention the King...
This thread is going OT...