RoastLogger with USB & webcam input

[GreenBean]

Before posting this revision I went to the trouble of testing the RoastLogger extensively on Windows (7, Vista & XP), OSX and Linux.

I have just found that compressing the distribution folder for distribution and extracting it for installation on Linux is stripping the executable permission from the included USB HID reader. This only affects Linux.

For Linux users who wish to read directly from a Victor 86 multimeter it is necessary to change the executable permission after extracting the files by navigating to the installation folder in a terminal and entering the following:

chmod +x USBHIDReader_Linux

Edit:
I have now included a .tgz version of the distribution on the download section of my website. Linux users should use this to avoid the problem discussed above.

[bruceb]

Ermmm… that isn't the ambient temperature Bruce, it's the environment temperature in a hot roaster.

Hmmmm, how do you measure that? Or where? In any case I thought that your roaster was actually refrigerating since the roasting temperature was lower than ambient! In fact, I like that idea so much I think I'll just stick with that.

[Tristan]

Will any USB multimeter work?

[GreenBean]

Hmmmm, how do you measure that? Or where?

I placed a thermocouple about 2 cm above the beans near the bean loading chute and towards the front of the roaster. This is probably not an ideal location and you will obviously get different results in different locations but I had to start somewhere.

[GreenBean]

Will any USB multimeter work?

The short answer to a short question is no, I am afraid not. Unfortunately there is absolutely nothing standard about the interfaces multimeters use.

This is all very much more complex than people realise and I know that others will also ask me to get it working with their multimeter so I offer a much longer answer:

Most Multimeters with a USB cable do not use a HID interface as it is more difficult and I guess expensive for the manufacturer.

The advantage of the HID interface is that Windows, OSX and Linux all provide a HID manager as part of the OS and all comply with more or less the same basic functionality.

This program is written to take advantage of the multi-platform nature of the HID interface and will only ever work with multimeters with a HID interface.

Even given the above there is no high level computer language that can work with a HID interface so I have had to write three different C++ programs, one for each OS to communicate with the OS's HID manager and pass the data back to the RoastLogger. The RoastLogger selects and runs the correct one of these depending on which operating system you are using.

The C++ programs have been written specifically to work with the Victor 86 C multimeter. I have mentioned that it may work with other Victor 86 multimeters such as the 86 B or 86 D but I do not have these so I can not test it. Success would depend on whether the manufacturer has used the same HID attributes and the same coding of the data. If they have it will work. I am confident that if I obtained these multimeters I could get it working with them reasonably easily as they will be very similar. If anyone has one of these I would be very grateful to know if it reads the data OK so I can add it to the list of suitable multimeters.

Other multimeters by other manufacturers would be more difficult. Unfortunately none of the manufacturers publish the information required. If they have a HID interface then given the multimeter and enough time I could make it work. Without having the multimeter in my hands or the manufacturers detailed data on the HID attributes and coding of the data I would not even try.

[bruceb]

I, for one, am very impressed. Thanks for your efforts on this. Even without a multimeter readout the program has changed my roasting routine and given me a great deal more information on which to base changes to my roasting profiles. I may try something similar to what you are now doing, but will use one of my Fluke meters with thermocouple and a second webcam (if I can ever find one of my old ones). I will certainly let you know how it works, if I get it working. thanks again, GB!

[GreenBean]

I, for one, am very impressed. Thanks for your efforts on this. Even without a multimeter readout the program has changed my roasting routine and given me a great deal more information on which to base changes to my roasting profiles. I may try something similar to what you are now doing, but will use one of my Fluke meters with thermocouple and a second webcam (if I can ever find one of my old ones). I will certainly let you know how it works, if I get it working. thanks again, GB!

Sounds interesting. It is a pity that your roasters bright red LED display is so different from the Fluke multimeters LCD display. Otherwise you could position your Fluke display adjacent to the roasters display and captured the image of both displays in the one webcam. It may still be worth a try, if you can find settings for your webcam that give a reasonable image of both displays. To make it easier to align the displays one or both can be upside down.

[GreenBean]

This is absolutely amazing, can't believe I missed this thread!

I've been looking for a solution like this for logging roasts as well as monitoring temperature on my distillation equipment.

With regards to the genecafe (because I have one), it displays the target and actually temperature intermittently. IIRC it flashes between the two every 2 or 3 seconds and/or when the temperature is adjusted. Could the software be modified to only read temperatures between the times that the roaster displays the target temp?

Sorry Tristan, I missed this post yesterday as it overlapped with one of my posts that changed the page.

The issue with the Gene Cafe display came up earlier in this thread. What you are suggesting could be done at some time in the future. I would be interested, for now, in how well the roast logger reads the display on the Gene and if there is some way to force it to only display the actual temperature, perhaps by holding a button for a few seconds. Even a "square wave" plot as it switches between the two readings would still clearly indicate the actual temerature profile.

[GreenBean]

With regards to the genecafe (because I have one), it displays the target and actually temperature intermittently. IIRC it flashes between the two every 2 or 3 seconds and/or when the temperature is adjusted. Could the software be modified to only read temperatures between the times that the roaster displays the target temp?

I have just had a look at a Gene Cafe owners manual and see that it states that the temperature display alternately displays the actual temperature for two seconds then the set temperature for one second. I had assumed in my previous answers on this subject that it would have a longer time period than that.

The roast logger takes readings from webcam images once every second and already contains a filter to filter out any one or two readings that are more than 2 degrees away from the previous good reading.

If the Gene Cafe manual is correct then the existing filter may already be sufficient to filter out the set temperature readings and just display the actual temperature readings.

The logger was not designed for the Gene and it assumes that it will get a set of at least three readings over three seconds within 2 degrees of each other to reset it to the correct readings. This will not be the case with the gene so it may never settle on a reading, especially if it starts with the set temperature.

If you want to test it I would suggest you do the following:

Set up the webcam as covered in the readme and help files, it is important to do this carefully to get a good clear steady image. If you see a reading in the results message area at the bottom of the main window that corresponds with the actual temperature you are done, it will then filter out the one second set temperature readings. You just need to click load beans to start logging.

If you do not see a reading or see the set temperature displayed click stop to stop capture and click start again as soon as the webcam image of the Gene display changes to the set temperature. This will give it two seconds to settle on the correct set temperature.

If you try this please let me know how it goes. I may then be able to change the existing filter, if necessary, to avoid the need to stop/start.

[Tristan]

Thanks for the explanation. I'll give it a go soon, but having trouble running the .jar install file at the moment though. I'm running OSX, tried everything, including terminal, that you suggest in the readme file, but the jar launcher that OSX just fails after 4 seconds. No error message, nothing.

Any ideas?

[GreenBean]

Thanks for the explanation. I'll give it a go soon, but having trouble running the .jar install file at the moment though. I'm running OSX, tried everything, including terminal, that you suggest in the readme file, but the jar launcher that OSX just fails after 4 seconds. No error message, nothing.

Any ideas?

I guess this is related to the version of OSX and/or Java that you are using.

As it states on my website, and in the readme files in the distribution, all of my programs require Java(TM) SE Runtime Environment 6 or above to run. This is available for all versions of Windows and Linux but for Apple this is only available for 64 bit Intel based Macs.

The following is taken from my website:

Apple Mac OS X - Apple have provided a suitable version of Java for 64 bit Intel based Mac's only.  This program has been tested on this version.  It is hoped Apple will issue a suitable version of Java for their remaining computers in the future.

You can test the version of Java on your system by going to my website and clicking on the RoastLogger Introduction section where you will see:

"Test the version of Java on your system: Sun Java Test"

Or open a terminal and enter the following:

Java –version

You should get a response similar to:

java version "1.6.0_17"
Java(TM) SE Runtime Environment (build 1.6.0_07-b06)
Java HotSpot(TM) Client VM (build 10.0-b23, mixed mode, sharing)
 
If the version is less than 1.6 then you need to update to a more recent version of Java.  If you have installed version 1.6 or above but the reported version is still less than 1.6 you need to make the latest version your default version of Java.  How this is done varies for different operating systems.  Currently it is necessary to take this step with Mac OS X Leopard which still uses Java version 1.5 as the default.  For Mac OSX Leopard set Java version 1.6 as the default version by running  /Applications/Utilities/Java/Java\ Preferences.app/Contents/MacOS/Java\ Preferences .

Hope this helps.

[Tristan]

Checked and double checked, I am fully up to date, but no luck.

[GreenBean]

Checked and double checked, I am fully up to date, but no luck.

Could you advise what Mac what processor and what version of OSX you are using. Also copy the output from the terminal to java -version.

You may also like to have a read of the "New Coffee Roast Database" thread. EricC had exactly the same problem with that program, we thought at the time that these programs were not compatible with OSX and would not run. We found in the end that Eric's computer was corrupted (although he had no other problems than running java) and as soon as he reformatted and reinstalled the OS and Java the same version of the program ran perfectly fine.

I now have two different Macs both run the program without difficulty. I actually wrote this program and did all the testing on a Mac.

[GreenBean]

To make installation easier for Linux users I have added a .tgz version of the distribution to the download section of my website. Linux users should download this version to avoid the problem of file execution permissions being stripped by .zip files.

As I was doing this I decided to include the latest version of the program which is available here. The version information follows:

Version 0.51 - 17/1/2010

Minor update to remove leading zeros from the DMM output.  This is for consistency with the output from the OCR tabs and does not affect the operation of the program.

[GreenBean]

An update is now available here that fixes two issues.

1. The previous release highlighted a bug that has existed in all previous versions of the program. The bug stopped the chart updating correctly when a previous log was loaded that contained temperature data as decimal values rather than integers. As soon as I saw this bug I realised that Ola (who's roaster has a display that reads to one decimal place) had mentioned this issue some time ago, Unfortunately I did not understand what he was telling me . So apologies to Ola and it is finally understood and fixed.

2. The USB HID reader in the previous releases worked on OSX 10.6 but not 10.5. It has been updated and now works on 10.5 and above.

Version information follows:

Version 0.52 - 19/1/2010

Fixed bug which stopped the chart updating correctly when a previous log with temperatures saved as decimal values was reloaded.

Fixed issue which stopped the USB HID reader for OSX working correctly with OS X 10.5. Now works with 10.5 or above.