Kurt: So the way I got started in the stuff Oh my name is Kurt Forsberg and I am the founder of Linux Automation. The way I got started on the stuff is I was at a common Linux user group meeting, and a gentleman by the name of Chris Negus was giving a presentation about his book “Linux Toys”, and he had these temperature sensors that one of the chapters in the book was about. And he said, “Unfortunately, these are no longer available.”
So I approached him after the presentation, and I said, “I work in electronics, I can probably reverse engineer that and maybe we can make those available again.” So we talked about it, I did a prototype, and we were talking about going into production; but that never happened. But I had these temperature sensors sitting around, and I have been a home brewer for about 12 years now (I don’t know, a few years at that point). So I decided temperature sensors I could use for monitoring my home brew. And monitoring turned into controlling.
It started out controlling the fermentation temperature and eventually went on to controlling the mash which is the unit we have behind us which is RoboHop 2. And we got a hot liquor tank at the top which is controlled by a module similar to this. This module controls four transistors for switching DC devices, 2 [Tray-x] for switching AC devices and takes two channels of input. So for the top burner on the hot liquor tank, it is using one channel for the gas valve, one channel to actually spark it to light the ignition, and then one channel to detect the flame. So this unit will control two burners and switch a pump on and off.
Starts with the hot liquor tank, heated up to 180 degrees, automated. From there we go into the mash tun which usually lives right here. The mash tun maintains mash temperature, automated, recirculating through the pump also automated. After the mash is completed, this thing will be full of hot water again, then we sparge through the boil kettle. The boil kettle turns on automatically at that point. And then once we are done boiling the beer with hops in it, we transfer it to our fermentation chamber which is also automated.
Tim: Now the beer tray behind you is made out of what?
Kurt: A server rack.
Tim: That is a craigslist finding?
Kurt: Yeah. Free stuff on craigslist.
Tim: Now the rest of your setup, which mean you’ve got the control over here, and you’ve got those things that they're controlling behind you....
Kurt: These controllers are simply I/O, so all the code execution takes place on a Linux computer. Right now it is a series of batch scripts. But we are looking for software developers who can help us build a web interface and a graphic interface to make it a little bit more user friendly.
Tim: Now you are using to control the making of beer. What are some other purposes that the same kind of controllers could be put to? Where do you see this going?
Kurt: We’ve considered doing greenhouse control, you can use it for home control, my colleague Ryan has it controlling the furnace so he can remotely monitor the temperature in his house and change it if he needs to. We’ve considered doing sprinkler system. Basically, I don’t know, anything you can automate, but we spend all our time brewing beer, so we haven’t explored many of those yet.
Tim: What kind of beer do you brew?
Kurt: We stick with mostly English style ales, but the west coast variety of English style ales. So pale ale, IPA, porter, with a northwest twist.
Tim: You’ve got the warm portions of the brewing process here, did you also automate the fermentation process?
Kurt: Yes, for fermentation, we have a water-cooled glycol chiller propylene glycol solution made out of a chest freezer (found on craigslist) and that uses pond pumps to recirculate the coolant to the fermenters. And each fermenter is individually cooled.
Tim: You brought up to this year’s Linux Fest the beer that you made last year?
Kurt: Correct. Our old technology Barleywine made it at last year’s Linux Fest aged it for a year.
Tim: You served that last night?
Kurt: We served that last night at the after party.
Tim: It went down pretty well?
Kurt: Well, there are a lot fewer people here today, so I think it went down pretty well.
Tim: All right.