WiFi Beerbug Initial Review

beerbug initial trial

Not long ago I received my third hardware example of the BeerBug, namely the current WiFi model.   Previously I had tested two previous incarnations that connected to the world using Bluetooth (see my blog posts tagged beerbug).  After seeing some good looking data from the new models, I took advantage of a reasonably priced upgrade process offered to Kickstarter backers to get the latest version.

Initial impressions were pretty good.  It has more LEDs than the earlier model to provide more information (though these could be documented better), and an integrated LiPo battery that so far has provided outstanding battery life compared to the older Bluetooth prototypes.  This BeerBug uses the Electric Imp platform to connect to a remote server using your home WiFi network, and from there data is accessible by smartphone apps and a web interface.  The hardware gets configured for home wifi by something they call blinkup where your smartphone flashes a coded signal onto a receiver on top of the device.  It is nice being able to see the data from anywhere you have internet connection, especially compared to the older version which required a windows device in bluetooth range.

I’d made a simple PVC holder to allow the “torpedo” weight to hang in sanitizing solution or water without occupying a fermentor, and used this to check the performance of the device.  Here the optional temperature sensor dangles alongside.

beerbug test rig

The software is not fully developed yet, though I thought it was in better shape that the earlier versions I had spent many hours trying to get working, exchanging dozens of emails with the ParasitX crew.  This time I was stymied trying to get the Android app to tare (i.e., calibrated to 1.000 specific gravity in water), receiving a message saying “did not receive a response from the imp servers.”  I thought I had a network firewall issue which led me down a fruitless path of trying to reconfigure my router and DSL modem.  Eventually I installed the iOS app and got the thing tared.  Even later I found that there is the ability to tare from the web interface, though this option was difficult to see.

I haven’t tested it in brewing yet, but here are some results from testing in water as I have done before, to check for drift, accuracy, precision, etc.   The very first run, below, had pretty quick drift up to about 1.005 in the first day or two but after that was steady with small variations of about +/- 0.002  specific gravity units.

beerbug initial trial

On around August 28 I tared it to re-zero at 1.000.  Instead of a vertical line in the chart as might be expected, there is at least one intermediate data point going down to after the completion of the tare, which is strange (see below chart).  I wonder if this is some sort of smoothing algorithm.  After having looked at some of the raw data from the bluetooth devices, I don’t miss seeing it, though the scientist in me is a bit put off  seeing a data point (as opposed to an interpolated line) where there should be none.

beerbug wifi longer test

Anyway, once I got the device set up initially it seemed to be working quite well overall with better consistency and usability than the bluetooth prototypes.  Supposedly the WiFi will connect from inside a refrigerator.  I look forward to using it with a beer.

Another BeerBug trial

summer porter beerbug

I forgot to deploy the BeerBug in my last batch until the primary fermentation was a couple of days in.  After making sure it was level and relatively well behaved (see the last post on this) I was eager to try the BeerBug but as it isn’t part of my routine now it didn’t occur to me until after fermentation was well underway.

Anyway here’s the data I collected, starting around 1.025 gravity and quickly going to terminal gravity:

summer porter beerbug

If you click to see the chart in full size you can see that the oscillations are not on the same pattern as the temperature fluctuations (which are from normal diurnal heating and the air conditioner cycling on).  Strange stuff.  There isn’t much if any drift, just oscillations of about 0.006 gravity points in amplitude.  Measuring with a conventional hydrometer found the terminal gravity at 1.011.

Additional BeerBug Testing and Review: More Stable, Less Drift

BeerBug level tare test

Since my last review of the BeerBug hydrometer I’ve had a chance to do some more testing.  At first the data was pretty poor.  I sent those results to the BeerBug folks who thought it might be because the device wasn’t level.  It seems pretty sensitive to this, as it couldn’t have been more than few degrees off.

I got a stick-on bubble level like this one, re-tared, and left it for a couple of days in some santizer solution (approximately SG 1.00 and with the taring should read 1.000 regardless).  The results were much better than I’d seen before:

BeerBug level tare test

There is still a little drift that seems to be temperature related.  The indicated specific gravity varied from about 0.999 to 1.007.  Probably because I tared at a time when the temperature was relatively low, the drift is mostly at the upper end.  It would be better to tare at the average fermentation temperature.

As usual, I have a batch of beer just coming out of primary so it will be a while before I can test it under actual conditions, but I think if it the device is kept level it will work well enough to ascertain the end of primary fermentation.

Another BeerBug, Another Review

new tare test

The BeerBug folks were kind enough to send me a replacement BeerBug (with a green LED instead of blue) in view of the problems I had with my early model.

I happened to have a beer fermenting so I tried it right away, but had some issues likely related to the line holding the torpedo weight being too long so that the weight partially rested on the fermentor.  And the beer was about done fermenting.

After shortening the line, I tried in again in a carboy of water to make sure things were sorted.

3g allon carboy

Normally the BeerBug is supposed to go to sleep after not talking to the app after a while, but in this first trial it never slept: the LED didn’t go to more the more dim flashing that indicates the low-power sleep mode, and the battery didn’t last very long.  Turns out you can soft-reset it by pulling the battery for a moment (it saves your data through this), but I didn’t do that this time.

Another trial of leaving it in water (starting with a new battery) for a while worked out much better:

new tare test

There is some drifting with the mild temperature fluctuations, but if you look at the scale you will see it is only about 0.04 gravity points.  The spike in mid-morning of May 12 is when I squired a little StarSan down the snout of the BeerBug just to see what sort of impact it would have.  Not too bad.  Overall this BeerBug seems pretty stable and definitely much better than the last one I had.

I look forward to trying it in a fermentation.

BeerBug Review

drifting and oscillating

UPDATE: a newer BeerBug unit seems to have resolved these problems – see Another BeerBug, Another Review.

SECOND UPDATE:  Further test results reported here

THIRD UPDATE: the currently most recent fermentation trial here.  For all my BeerBug stuff, check my posts tagged BeerBug

To follow up my first impressions, here are my experiences after using the BeerBug hydrometer to measure the gravity of a batch of beer as it brewed.  As one of the first recipients of the device, I understood that there might be some snags, and so far the people at BeerBug have been very responsive in answering questions and the like.  For example, several of the issues I had were resolved by new Windows software.  Despite this, I found that my BeerBug is not (yet) usable for its intended purpose of measuring gravity during fermentation.

The beer I’d planned was a weizen. After letting the torpedo stabilize in water for a couple of hours while I finished the brew, I put it in the wort which was intentionally under-pitched.  The first few hours showed what seemed to be a vigorous fermentation with a quick drop in gravity, but there was actually no airlock activity.

Incredible fermentation

This was my first encounter with a wicked tendency of the BeerBug to drift.  Shortly after this, the battery died: turns out the BeerBug has a built-in memory so it’s better to leave it disconnected from the Bluetooth connection to the PC which will spare the battery and also allow the on-board software to average the collected data (over a user-selected period of time, recommended as 10 minutes) while discarding any odd outlying points.  The data was also preserved while swapping the battery.

With the new battery the BeerBug seemed to work OK for a few days.  The weather was such that the air temperature in the basement varied considerably between day and night, but the beer in the 10 gallon fermenter held a relatively stable temperature.  There’s not yet an immersed thermometer and as a result, it seemed that the temperature compensation of the BeerBug over-corrected in calculating the specific gravity, as seen in the beginning of the below data with diurnal swings.

the beginning of the end

The chart immediately above begins at a time near the end of fermentation with the BeerBug SG matching closely with that determined by a conventional hydrometer.  But a downward drift began that had the SG at times below 1.000, well below the actual beer which finished at 1.011.  Then the depicted gravity started drifting upward substantially.

Around the time the above chart ends, I bottled the beer and put the BeerBug in water to see what it would read.

Then things got really weird:

drifting and oscillating

The BeerBug went from the fermenting beer into water at around the time of the big spikes in the above chart.  The upward drift continued and then some really strange oscillations began as well.  I have no idea what caused this.

Here’s a photo of the “guts” of the BeerBug after I opened it up so see if some crud from the fermentation might be causing some problems.  There was a little yeast but it didn’t seem like enough to produce the weird results.  The oscillations happened even after I cleaned up the little bit of material in this photo.

bug guts

In summary, the performance of the device has been very erratic to the extent it’s not really useful for me right now.  Hopefully this can be fixed in software, though so far the cause of the drift and oscillations remains obscure.

BeerBug Wireless Brewing Hydrometer: First Impressions Review

Capturing the flashing status light on the head unit

Today I received my BeerBug Digital Hydrometer as an early backer of their Kickstarter.  I had some minor issues with the setup, but they were quickly resolved by email from one of the project’s principals.  The device is pretty elegant, with a weighted Teflon “torpedo” suspended in the fluid, connected to a head unit by monofilament line.  The head unit has a strain gauge (correlating the weight of the torpedo to specific gravity) and communicates readings by Bluetooth.

At this early stage there appears to only be Windows software – a screenshot below shows some of the expected drift when first using the device (readings are very steady now as I write this post) – at the time I also had it installed incorrectly which couldn’t have helped.

The initial release of the Windows software

The initial release of the Windows software

Here’s a photo showing it in a three gallon carboy, with the white torpedo in water.

showing the "torpedo" suspended in the liquid

showing the “torpedo” suspended in the liquid

Here is a close-up showing the head unit

Capturing the flashing status light on the head unit

Capturing the flashing status light on the head unit

I am very excited to try this in a batch of beer!