Completion Nearing

A project log for Bin Temperature Monitoring System

A grain monitoring system that will cost about $500CAD (raw materials) instead of $4000 CAD. Also open source instead of closed source.

kody-alan-rogersKody Alan Rogers 08/27/2021 at 15:300 Comments

First I should apologize about the lack of updates, and for my next project I intend to to logs more often.

The first iteration of this project is more or less completed. I am currently waiting for what I hope to be the final PCB design to arrive from Oshpark, and one of the earlier PCBs is connected to 3 bins that each have a cable and are reporting well.

At the moment it is just a monitoring system (no alerts) where current and past temperature data can be viewed on the Arduino cloud. I know when the project started it was going to be 100% alert based, but that changed when I realized how easy it was to launch things on the Arduino cloud. 

The current monitoring is going well, except that some of my dad's peas were increasing in temperature drastically for a while, so it would seem that the design works well.

One thing that may have to be changed varying on deployments is the size of the pull-up resistor on the PCB board for the DS18B20 sensors. If too large a resistor is used on the long cables then the sensors will not read, and for one of my dad's bins this was the case for the standard 4.7K ohm resistor. In this case a smaller resistor needs to be used, and I will describe this in the instructions in more detail. 

That brings me to the last major work that needs to be done ..... documentation. It is not my favourite part but it is very necessary, and I hope to have very descriptive documents for this project. The instructions on this project page will be how to build the device from scratch, but there will be other documents on the GitHub on how to build each part of the project separately. Also in the GitHub will be a document describing how to simply assemble the grain sensor with finished cables, an Arduino MKR board, and an assembled PCB board. 

Of interest to some people might be that I plan to sell kits with all the disassembled components, as well as assembled monitoring cables and assembled PCB boards. The price for the disassembled components will be just above what I paid for them (enough to cover my time of packing it up), so maybe around $550 or so (all together separately the components are $500 or so). A kit with the cables and PCB assembled it will be about $1000 (I calculated this price roughly by paying myself $50 an hour). Both of these kits are to monitor four 5000 bushel bins. A wild card in the price is how spread out your bins are since if the two bins are close together and another two bins are further apart (like my dad's) they way it is set up now a lot more wire will be needed. In a different project log I will give a more updated explanation of pricing.

The price to run the system once it is assembled is the price of an Arduino IoT account, which for up to two devices is free, and the price of communication. When I was using the GSM Arduino the communication costs were about $10 CAD per month using hologram, but it will vary based on how often you want to report the temperature.

For anyone interested in this project please do not hesitate to contact me, or to express interest in purchasing the kits.