i'll wade in with my opions too
Firstly congratulations on getting to final year!
General I would say consider if there are any mechnical/process elements to the design that could be passed of to another department's students for their design project - that will take the hassle off of you. Also is their any workshops (that are experienced with SS and Food & beverage work) that have an association with the university and could "donate" some time for anything that needs to be fabricated, in exchange for getting to brew on the gear and their name in lights
Also really sit down and map out what you want from the end project, and by end I don't mean what you can get done in a semester/year... consider the project as something that will be passed off to next years students to implement something new. Some of my suggestions will probably fall into this catagory. Select what you want to (and can) do in the time you have but document the future ideas/concepts.
1) Given a BeerXML file, uploaded via dropbox, the mobile app will parse the XML file, transfer it to the beaglebone, and the user will only have to put grain into the mill hopper, add hop additions during the boil (which the app will remind you to do), and add yeast at the end.
Automatic hop additions would be cool... one step further automatic grain and hop weighing from hoppers, this would be a good future extension.
2) Given no BeerXML file, or if the user prefers doing the process them self, options will exist on both the mobile app and beaglebone HDMI interface to control each individual brewing process such as: heating strike water, mashing, recirculating, transfer to kettle, etc.
Could the main UI be the second part of your comment, with the ability to import the BeerXML into it to autopopulate the feilds?
3) All valves will be edit: electric ball valve controlled (either 120V AC or 12V DC) I haven't decided.
If you can I would go 12VDC just for safety's sake
4) Tubing will be 3/8" Silicon with 5/8" outside Diameter.
Consider hardpiping with SS tube - check out if you can get donated/subsidised fittings,etc. from a local supplier
5) Fittings will all be 1/2".
6) Pumps will be DC. Now, I know many like March and Chugger pumps, but hear me out. With DC pumps, I can achieve 3GPM max at 0' of Head. In reality, the most head your pumps should see is maybe 2' if you're accounting for resistance in the tubing. Given that I never mash out at 3GPM, and transfering from kettle to fermenter isn't time sensitive, I've selected the US Solar 12V 3GPM pump. ALSO, with a DC pump, and flow rate sensors, I can MATCH flow rates of the Lauter Tun and the Mash Out by varying the voltages to the pumps. This means: you don't have to operate ball valves to match flow rates. Not that this is a big deal, but I think it's really freakin cool! I've been using the US Solar pump in my homebrewery, which consists of 1 Keggle for a HLT and a Kettle, a 5 Gallon rubbermaid cooler to store hot water, and a 10 gallon home depot mash tun. Also, pumps cost $70. Cheap as hell.
From what I have read the 12VDC pumps do not reduce speed with reduced voltage and potentially running at lower voltages will burn out the motor, Just confirm that your control method will work. I have seen some info that Ac pumps can be "speed" controlled by PWM with no ill effect, but not 100% sure a PSC motor can be controlled long term for this (I have done it but my motor hasn't blown up yet so I don't know if it will keep going
). Someone at Uni should be able to advise more.
Future project could be to actually look at making a low cost modulated control valve based of the OSCSys style
7) I'm designing this system for 15.5 gallon keggles. Now, If I have time, I'll try and make it possible to make this system scalable to 1 bbl, but I can't guarantee it.
I don't think you should worry yourself too much on scaling up - since you will be dealing mostly with the control side of things for the project bigger batch means bigger gear but the control will stay pretty much the same.
8) Sensors I plan on using include: 5 digital thermometers for: 1 in HLT, 2 in Mash Tun (averaged out), 1 in Kettle, and 1 in output of wort chiller. Flow sensors throughout to measure speed of fluid transfer. Volume sensors in Kettle and HLT. (I may add a PH monitor to the kettle, but my water is so good in Oregon that it's just not worth it to me.)
Do research on the volume sensing methods and their lmitations... then tell us what you think is the best
How are you going to do flowrate sensing?
A detailed PFD/P&ID will help you visualise where your instrumentation is and if you have to much / to little.
As a "fun" exicise consider running a HAZOP to give you some experince in them - this project would be pretty well suited for one to be done. Contact a local Engineering consulatant and I bet you they'll have someone that can spare a few hours to come out and talk you guys through it. It will give you something extra for your report/presnetation at the end.
9) Wort Chiller will NOT be a plate chiller (trying to be economical so everyone can implement this project). I'll be using 25' copper tubing, and a silicon hose to cover the tubing creating a counterflow chiller. (This is also easier to clean than plate chillers).
Again don't try and design this to use specific equipment just so others can use it - a heat exchanger is a heat exchanger, if you cosider a tube-in-tube to be best for your porpose use it, but it will make no differnce if someone wants to use a plate chiller for theirs.
10) There will be a clean in place (CIP) function on the remote
As mentioned above the "solarpumps" will not run a sprayball effectively, even a standard 815 March/chugger will struggle. I would go with a SS chugger and consider something a bit stronger than PBW if you want a good clean. 2% caustic soda should be good, just make sure you take all the precaustions. Future project automatic CIP kitching for the brewery!
11) Full integration between Brewtroller (arduino based), Beaglebone (linux based), and a webapp (java/html based). Realtime feedback on all temperature sensors, etc.
What is the brewtroller doing in this? Look at the brewtroller source code for ideas but I don't see any benifit from being able to talk to one. Or are you using the brewtroller to control the brewery as per it's standard package and the Beaglebones to do the extras?
12) Ability to be mashing one beer while another beer is boiling in Kettle! I estimate this could save upwards of 2 hours per batch if timed correctly.
Instead of time savin, maybe look at energy savings with heat recover (Someone mentioned it, using the hot cooling water as strike water in the next back), markers will give you more bonus pioints for being energy efficient than saving time
13) Oxygen aeration: I'd appreciate any ideas on this. I'd prefer NOT using an O2 cylinder, mainly because it's expensive and I want to keep this cheap for everyone.
Again design for what you want to do and others can either use it or not. I would guess the uni has a supply of oxygen so use that.
14) Ability to use Natural Gas / Propane / Electric for heating. Ability to use a combination for heating. Pulse Width Modulation via SS Relays to maintain HLT temperature instead of valve control on a propane / natural gas burner. This means: Use gas to achieve desired temperature, then maintain temperature / boil via Electric. Another option is to have a regulator in front of the Kettle to maintain boil with gas, because it's definitely a cheaper heat source.
Are you sure propane is a cheaper heat source? I would not mix gas with permenatly mounted electrical due to the need to watch where you cables are located and sheiled. Go electrical - easy to implement control of the heat source
15) Control over mill by using a motor I stripped out of my old washing machine.
Maybe leave this one out of the project and others can develop a mill speed control in future. Just state the projects boundry is milled grain is feed to the system.
16) I will not be using a hard panel monitor to display the current status of the system. Instead, I will be displaying the current status on a custom GUI outputted onto a crappy old computer monitor via beaglebone.
17) Easy Easy Easy network connection between mobile app, beaglebone, and router.
18) Most importantly, please list any features I've forgotten to add, or features you'd like to see. I'm not offended if you don't like my ideas, because we can only improve through discussion. I'll post new features below here from now on.
Again really sit down and detail what the limits of the project are and make sure you can do everything you set out to do in the time you have... if not take something out. Keep in mind to try and hand this project to the next year, you may find that you started the Purdue University Microbrewy
Have fun
(and sorry if I sound like a dick in any of that!)
Edit: After reading some of you other replies - is this going to be located at the uni or in you house? I would suggest pushing for it to be the university's property as you will get more support if it is tied specifically to the univesity and potentially has multiple years of input into it.