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46  Using Arduino / General Electronics / IC with internal tempreture sensor and analog output on: April 16, 2013, 11:54:30 am
Hello,

I am looking for a reliable ambient temperature sensor (integrated in an IC) with analog output (0 to 5V) to be read by arduino.
Note: Thermistors are not an option for me.

Thanks
47  Using Arduino / General Electronics / Re: Fast Response - Contactless Thermometer to Arduino on: April 15, 2013, 01:09:16 pm
Hi Billo and BoardBurner,

Thank you guys for your responses.
So here is what the system is about.
First you have to know what this is: http://en.wikipedia.org/wiki/Shape-memory_alloy
what I am doing is testing a piece of this material to find a very high cycle behavior like (100,000 cycles)
I am heating the wire electrically using 14 A in less than 100 ms from room temp to 100 degrees C.
right now we have position and force feedback which are used for control. I want to add temperature to the system not as feedback but just raw data to be analyzed later( hence NO processing).
the position and force are working and logging and analyzing fine. My problem is a temperature sensor (non contact).

To answer Billo question about why noncontact? I do not want to take out heat from the wire, no matter how small, because if I take out heat, then it will change the behavior of the wire.

I have consulted this page which has a list of all companies that manufacture IR temp sensors: http://www.directindustry.com/industrial-manufacturer/infrared-temperature-sensor-71767.html
I came across this which has the closest match to what I am looking for: http://www.micro-epsilon.com/temperature-sensors/thermoMETER_CT_basic/thermoMETER_CTfast/index.html
its the same company that Boardburner mentioned.
what I am exactly looking for are these specs:
- fast response (1 ms or less) (under 10ms is OK too)
- measurement of spot size of 0.5 mm
- measurement range of 0 to 200 degrees C
- 0 to 5V analog OR digital output to be read by microcontroller.

Also I think using photomultiplier and kinda making my own sensor would become too costly and not very accurate...

Thank you,
48  Using Arduino / General Electronics / Re: Fast Response - Contactless Thermometer to Arduino on: April 12, 2013, 03:41:36 pm
I kinda need the response time to be 1 ms or less.
I have system that changes temperature from room temp to 100 Degrees C in about 100 ms. Then it cools back down to room temp in 3 to 4 seconds. I want to be able to record this change of temperature.
So a response time of 100 ms is kind of useless!

I was searching online about only the response time... Does any company make non contact digital sensors with 1 ms response time???

Thanks
49  Using Arduino / General Electronics / Re: Fast Response - Contactless Thermometer to Arduino on: April 12, 2013, 03:13:40 pm
Wow man... you rock!!!

I cant find the datasheet for this thing though... what is the response time of this thing?
50  Using Arduino / General Electronics / Re: Fast Response - Contactless Thermometer to Arduino on: April 12, 2013, 12:53:54 pm
I kinda need a off the shelf part.
I would imagine building optics would cost more than that.
Could you give the part for your 'solution'?

Thanks
51  Using Arduino / General Electronics / Re: Fast Response - Contactless Thermometer to Arduino on: April 12, 2013, 12:41:40 pm
Thanks for the response Billo,

This is a good part, but I was looking for something that can measure surface temp of a wire o.5 mm diameter. This part is not suitable for this. Also I did not find the response time for it.

Thanks,
52  Using Arduino / General Electronics / Fast Response - Contactless Thermometer to Arduino on: April 12, 2013, 12:09:03 pm
Hi,

I looking for a fast response ( 1 ms or less) contactless (laser or IR) Thermometer that can accurately measure surface temperature of a wire (0.5mm diameter).

Does anyone have any ideas as to where to look? What company? etc...

Thanks
53  Using Arduino / Programming Questions / Re: Serial Communication bottleneck on: April 10, 2013, 01:55:20 pm
Hi Rob,

Thank you for taking the time to recognize this. You are absolutely right!!! thanks a lot for that.

The fact is that this line is blocking everything: myPort.readStringUntil('\n');
The 'if' statement has nothing to do with it. I commented out the if statement and it still was lagging.

Now, how do I process each character and achieve the same result as I am trying to do, but much faster?

Thanks
54  Using Arduino / Programming Questions / Re: Serial Communication bottleneck on: April 10, 2013, 01:18:10 pm
Thank you guys for the input.

I tested another program to measure the speed of the serial data comming in. Here it is: (it is a modification of the example code on processing website)
Code:
import processing.serial.*;
 
Serial myPort;    // The serial port
PFont myFont;     // The display font
String inString;  // Input string from serial port
int lf = 10;      // ASCII linefeed
 
void setup() {
  size(400,200);
  println(Serial.list());
  myPort = new Serial(this, "COM5", 57600);
  myPort.bufferUntil(lf);
}
 
void draw() {
  background(0);
  text("received: " + inString, 10,50);
}
 
void serialEvent(Serial p) {
  inString = p.readStringUntil('\n');
}


This code displays the data steam as fast as the arduino.
I think the reason that the original code is slow is because of write speed of processing. I am writing the serial data into an array and I think thats why this thing is very slow.
Correct me if I am wrong.
Is there a way to store the data faster into the Data[] array.

Thanks
55  Using Arduino / Programming Questions / Re: Serial Communication bottleneck on: April 09, 2013, 07:07:02 pm
The code is intellectual property of my company. Thats why...

Let me ask my question another way.
Is there any other way make the comm link between arduino and processing faster (not necessarily serial) ? I need at least 1MB/sec of transfer rate.

Thanks
56  Using Arduino / Programming Questions / Re: Serial Communication bottleneck on: April 09, 2013, 06:29:21 pm
I can't post the code.
this is the only relevant part that I am having problems with.
57  Using Arduino / Programming Questions / Re: Serial Communication bottleneck on: April 09, 2013, 06:16:20 pm
Hi Paul,

You can assume the whole processing program is just reading and storing the data into an array (the code). I tried this myself to narrow down where the lag is occurring. The 13 second lag is because of this section.
The Arduino is sending 6 sensor values every 5 ms for 5 seconds and then it stops.

Thanks
58  Using Arduino / Programming Questions / Serial Communication bottleneck on: April 09, 2013, 05:54:31 pm
Hi,

I have a serious problem with how the PC is receiving serial data from Arduino. I am trying to send a large amount of data from arduino to pc using serial comm. When have the serial port window open, the data steams nicely and there is no lag between sending and receiving. But when I use a Processing program to read this data stream and store it in an array, there is a huge amount of lag. For example, I am streaming data from arduino for 5 seconds and it takes an additional 13 seconds for the processing program to finish recording data into an array. I am reading the data like this on the processing side:
Code:
case 2: // write incomming data to large array
      if( myPort.available() > 1 ) {
        myData = myPort.readStringUntil('\n');
      }
      if ( myData == null ) {
        myState = 3;
        break;
      } else if ( myData != null ) {
        Data[n] = myData;
        n++;
        myData = null;
      }
     
      break;


Someone please tell me what the hell the processing program is doing that it is taking so long to finish this simple task.
Is there a way to make it faster?

Thanks
PS. I know my post is more directed towards processing, but I thought there are more people here too.
59  Using Arduino / Programming Questions / Re: ints and long calculation on: February 07, 2013, 03:10:27 pm
how come?

I changed the type of variable 'a' to long. So the operation should return a long variable. shouldn't it???
60  Using Arduino / Programming Questions / Re: ints and long calculation on: February 07, 2013, 02:57:54 pm
I am using arduino mega 2560. so the ints are 16 bit long.
so I guess an int calculation will return an int...

How about this:

if I have the following variables:
long a = 10000;
int b = 10000;
long c;

c = a * b;

what will be the value of c?
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