Robotic Floating Slurry Agitator

H.A.M

Hi guys,

I posted here before about a project I am doing on the safety of slurry tanks. The main aim of the project is to produce a product that will improve farmers safety around their tanks. I came up with a wide range of ideas and filtered through the best of them.

I decided to concentrate on keeping the slurry agitated as it will stop crusts forming and therefore stop the build up of harmful gases. The aim is also to keep farmers away from the tank as much as possible.

The final product that I am thinking of going with will be a robotic floating agitator. This will be a good way of constantly keeping the tank agitated and also eliminating the need for the farmer to agitate with a tractor. The agitator will work in a similar way to robotic lawn mowers or vacuum cleaners. It will have a main docking station at the edge of the tank and will complete agitation cycles around the tank.

The mechanics of this system has not been decided but I am in the process of it. Thats why I am here!

Do people here think that this is a good idea? If so, can you suggest any methods of powering the device? Initially I was thinking of battery power but I am now doubting that this method will be powerful enough to properly agitate a tank. Other options could be powering the main dock to the mains and tethering the agitator from this.

Agitation could be done by propellers or by aeration or by any other method that would get the job done!

Feel free to give any opinions you have on this idea!! I am just looking for some feedback from more farmers in the country!

Thanks in advance!

againstthetide

Use the roomba model and have it follow a path around the tank return to a doc for charging seems to be the way to go.
Not sure how you could keep the slurry out of the charger and away from the electricity though.
Mayne an airlock type system where the unit seals against a receiver pipe and automatically blows the slurry out of the pipe before exposing the the charging mechanism?

Timmaay

Hmm the current aeration systems are just a network of pipes, with very little to go wrong, like here http://www.dairypower.ie/html/slurry.html. Getting a robotic system to come in at a lower cost than the above system, and for it to be more reliable is going to be very tough I think personally!

Actually on second thoughts, the Dairymaster system above would be difficult to retrofit into an existing tank, as it probably needs to be completely emptied to lay the pipes on the floor, so some sort of system similar to it but much easier to retrofit would be a good idea.

pakalasa

Remember, it's not just about getting something that works, it needs to be cost effective too. A typical farmer has to look at it and think that's worth getting.
There are robotic slurry scrapers on the market too. Similar idea, I guess, but above the slats.
http://www.youtube.com/watch?v=bphBIwv5Vp8
http://www.youtube.com/watch?v=5FK2q8jn6vA

How about a device that could fit down through the normal slats from above and agitate that way. It could be connected to a standard air compressor. Could only be used when the shed is empty of cattle.

H.A.M

Timmaay wrote: »

Hmm the current aeration systems are just a network of pipes, with very little to go wrong, like here http://www.dairypower.ie/html/slurry.html. Getting a robotic system to come in at a lower cost than the above system, and for it to be more reliable is going to be very tough I think personally!

Actually on second thoughts, the Dairymaster system above would be difficult to retrofit into an existing tank, as it probably needs to be completely emptied to lay the pipes on the floor, so some sort of system similar to it but much easier to retrofit would be a good idea.

Yeah I think those aeration systems are a pain in the arse to install. The tank has to be completely emptied and cleaned out first! They are grand for new tanks to be fitted before slurry enters. As far as I know these systems can cost between €15,000 to €20,000 to buy and install? Can anyone here verify that as I could be wrong??

Thanks for the replies lads keep the opinions coming

blue5000

Could you power it by cows walking on a moving fluid? Something like 2 interconnected rubber bags with a generator located where the fluid moves from bag to bag as a cow steps on it?

maxxuumman

One thing that should be kept to a minimum when it comes to sh1t, is moving parts. To make something that is going to sit in **** 24hrs a day 7 days a week and keep it stirred would need to be as simple and as trouble free as possible. Remember you are dealing with 3 important factors, 1- deep tanks, 2-gases,3- mechanically retarded livestock farmers. you don't want a farmer having to "get in" to fix a breakdown.
To be honest I think the aeration system would take alot of beating. Minimal moving parts and any breakdowns are above ground level. I don't think the system is as expensive as was mentioned. I got a quote for one a few yrs back for a 60 x 60 tank, I'm not sure but it was coming in under 10k€. It would have been less if the tank had been in 2 or more sections, because smaller air pump could have been used. So not overly expensive.
Any realstic system is going to involve pumping either liquid or air, to keep things moving. Air is easier/cheaper pump, and has the additional free action of rising to the top, stirring as it goes.

St. Leibowitz

Just a thought. If going a battery and returning to dock for charge method, is there any danger from arcing when docking ?? I presume the methane concentration could be high enough to flash, especially after agitation ?? Or maybe the idea is to reduce the concentration through frequent agitation.

pakalasa

St. Leibowitz wrote: »

Just a thought. If going a battery and returning to dock for charge method, is there any danger from arcing when docking ?? I presume the methane concentration could be high enough to flash, especially after agitation ?? Or maybe the idea is to reduce the concentration through frequent agitation.

You would have to use EX rated switches and components. These are suitable to work in explosive environments. The circuit can be made Intrinsically Safe also, which prevents shorts like you mentioned from occurring. To be honest, you're opening a whole new 'can of worms' when you operated electricity in explosive environments, so best avioded, if possible.

keep going

am i the only one that think this idea is nuts

Tipp Man

keep going wrote: »

am i the only one that think this idea is nuts

I'm inclined to think the same

The current aeration systems on the market will take beating for simplistic sake alone

Timmaay

keep going wrote: »

am i the only one that think this idea is nuts

I got there before ya but I was much more diplomatic about it

H.A.M

keep going wrote: »

am i the only one that think this idea is nuts

That's fair enough and I appreciate it! I must just remind you that this is just a college project rather than a product that will be put to market. That said however I do hope to design the best possible product I can!

The idea may seem a bit far fetched, however I honestly do think that (if it could be worked out properly) it could really improve on the current aeration systems.

I did a lot of research and found that hardly any regular farmers had aeration systems installed. The fact that the tank would have to be emptied completely in order to install seems to be a massive drawback as well as the price. My thinking is that if this "robot" could just be placed into the tank by means of a dock that it would seriously reduce installation cost and hassle.

As regards the docking station my aim would be to have a platform that would rise up and down in accordance to the height of the slurry. The platform could drop the agitator into the tank when needs be and collect it after each cycle. Thus not having any connector points submerged in slurry. It would also solve the problem of the agitator being covered in sh1t 24/7.

Anyway im only talking sh1t at this stage (Pun fully intended)

maxxuumman

What's the project on, health and safety or slurry management. There might be more workable ideas here, if a broader starting point was given

pms7

I think it is a good idea, if you can get it to work. Why not have it connected to a long cable for power?
Not sure of the best method, propellor or air?
Let us know how you get on.

PMU

what about a wind powered agitator

keep going

better explain my earlier statement-i just think putting expensive kit into slurry 24 /7 is asking for trouble and would suggest a better alternative is some sort of biological additive that might also have other benifits. i know there are some products available but there does seem to be market penetration for some reason.as posted earlier can you give the scope of your project and we might be able to add something

H.A.M

My project has a massive scope. The course is product design and the area I picked was slurry tank safety. So basically I had to design ANY product that made slurry pits safer. Simple as that.

Anyway, I have chosen at this stage that I am more or less going with this idea and I am happy with it. The stage I am at now is finalizing how exactly it's going to work.

I like the idea of a power cable going from agitator to dock. This is one of the only ways I can see the power being sufficient enough to drive the agitator (without the use of a tractor).

What I am wondering is, how deep would a propeller or air blower have to go under the surface of the slurry in order to be effective? Or is this a major issue?

Thanks again!!

49801

how about a robotic pod power by pneumatic's same as an aeration sytem but on an umblical. so no need to lay pipes. pneumatic also used for propulsion. as someone else said keep it simple

have it crawl the floor with the main air outlet facing up... take some inspiration from those pool hoover type things maybe... could be an aeration retrofit then.

https://www.youtube.com/watch?v=70FhsNGntZQ

sorting the navigation is the tricky part. Think it would have to be an active system with broadcast unit say in each corner of the tank to constantly tell the pod where it is. These technologies should of come down in price with the advent of gps in recent years.

things like interal supporting pillars would be a complication.

We installed an aeration system with laid pipes retrospectivley... was not fun but was doable. They are a good job alright but water is the key!

just a thought on the proplustion you could possibly put airoutlets around the perimeter to aid proplustion like a jet driving a plane forward.

those are my hairbrained thoughts for you.
best of luck with it

freedominacup

49801 wrote: »

have it crawl the floor with the main air outlet facing up... take some inspiration from those pool hoover type things maybe... could be an aeration retrofit then.

https://www.youtube.com/watch?v=70FhsNGntZQ

Ya beat me to the punch with the pool cleaners. The mapping husquvarna probably have that sorted with those robot lawnmowers. They memorise the layout early on and then just work to a system after.

I don't think you're reinventing the wheel here rather pulling a good few already working tecs together. It might have a wider market than you think with all of the treatment plants recently installed. Westfalia might be worth a call if you van get a working design to prototype. I always wondered how a milk machine manufacturer got a name with seperator in it. Turns out the seperation is solids from liquids in treatment plants. I saw their gear in more than one treatment plant.

bbam

I come from an engineering maintenance background and your ignoring the premium rule in design.
I presume they still teach the KISS rule, Keep It Simple Stupid!

The submerged air agitation systems seem to work well with no submerged moving parts.

It will be impossible to design a "robot" style component to be so regularly immersed in slurry that will last. Or be economically affordable anyway.

I think your getting drawn in by thinking a robot will look good as a project, but as a product it's doomed.

I don't mean to be too negative, it's a very interesting and relavent topic.

Perhaps developing the air systems where they are easily installed, without emptying the tank. Go for a realistic project, better in the long run.

I spent well over a decade maintaining various robotic automated equipment, some of it in agriculture. What you are talking about cannot be done on a scale that would be in any way affordable.

bbam

Your also designing a system where a person will need to go down into the tank to maintain, possibly on an annual basis. Thus creating the exact situation we want to avoid.

F.D

honestly, if i was putting money into anything it would be a seperation system of some sorts, if you have safety in mind how about coming up with a different version of the ones that is out there at least then the only component that is in the tank is the hose sucking it out, try and design it in such a way that the liquid its putting back in is done under pressure to bubble it up or something