Mugsy

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Precision

Hey folks! Hope all is well today. Gonna jump right in...

Water Flow Control

I'm extremely excited to show everyone what kind of precision we were able to get with Mugsy's water flow controls. In the following demo, there was variance of 1 gram during the bloom. As the brew progressed the variance compensation caught up and allowed us to hit our extraction targets perfectly.

Demo Pour Over Settings: Step, Seconds, Water(g)

  • 1, 30 seconds, 50g(bloom)

  • 2, 45 seconds, 100g

  • 3, 45 seconds, 100g

  • 4, 45 seconds, 100g

  • 5, 15 seconds, 50g

Total time: 3 Minutes

Total Water: 400g

Video is sped up and I'm a second or two late starting the stopwatch.

So yeah, that's pretty great! I expect that we will see an average variance of 0-2 grams of water per brew cycle. Adding that second motor controller seriously improved our ability to control water flow. 

I was also able to update the water pump controller code to utilize the same command chaining that the cone stepper utilizes. So you can send all water flow commands at once and the system will handle it perfectly.

Command example (Pour Step, Flow Rate, Time On, Time Off) : <Bloom,4.1,3,2><2,4.1,4,2><3,4.1,5,1><4,4.1,3,5><Final,4.1,4,2>

Here is the serial terminal responding:

Im using fake timings here as a quick example.

When you enter your coffee weight, total water and brew timing preferences Mugsy automatically calculates the correct flow rate, number of steps and each step's on/off timings for the best extraction. It then sends these values over serial and executes the pour over. Pretty damn nifty if you ask me!

You can find a copy of the motor control Arduino code here: https://github.com/margyle/MugsyDev/tree/master/arduinoScripts

The flow calculations are in python and I'm still cleaning that up for upload.

Where We Are At

  • Flow rate testing is done and done

  • Heater testing is at 75% complete

  • I need to add tiny heatsinks to our boost converters. Temps are currently within spec but they are getting warmer than I am 100% comfortable with. This is not a blocker and more of a QA safeguard. I will have the heatsinks on hand tomorrow.

  • Servo testing started this eve(this one is quick)

  • I'm just getting started on complete brew testings(tomorrow).

  • I still need to set up a clear panel head unit for folks to compare to(as discussed on the community forum)

  • I'm about 24 hours behind on email/dm responses. If you are waiting, apologies. I will be getting back to you ASAP.

  • Still need to release the cloud machine control links

Tomorrow I will be adding in the new command chaining code to the main runtime. Once thats done brew testing will start. 

I have an additional 2 hours or so of interface work to do, mostly related to the recipe creation functionality.

OK, next update will be on Thursday. If brew testing goes well I should be able to give an OK on shipping prep. 

I'm feeling really good about where we are at today. These systems are running better than I had even planned for. I hope all of you are feeling good too and I'm really looking forward to our next update!

Cheers,

-m