13. Applications and implications¶

UPDATE: See final project page for updated scope, project, and everything else!

Learning outcomes - Define the scope of a project - Develop a project plan

Have you answered these questions? - what will it do? - who has done what beforehand? - What will you design? - what materials and components will be used? - where will they come from? - how much will they cost? - what parts and systems will be made? - what processes will be used? - what questions need to be answered? - how will it be evaluated?

The Project¶

For my final project, I propose to build a temperature regulation system for an offset barbeque grill used in smoking meats.

Temperature regulation is an important aspect in the preparation of smoked meats. Too high a temperature, and the meat will dry out before the structural proteins can fully break down. Too low, and the meat will be in a dangerous position for pathogens before the meat can cook or take a much longer time than expected. Therefore, maintaining the proper temperature of about 225℃ is paramount. The first part of the object will consist of a k-type thermocouple paired with a thermistor to determine the temperature of the grill chamber. An LED display will show the ambient temperature and the chamber temperature. To maintain the temperature, a separate unit will be housed near the air intake of the offset smoker box equipped with a radio receiver and a fan. Should the temperature drop below 225, a radio signal shall be sent from the temperature sensor to the fan unit. The purpose of this is to introduce additional oxygen into the coal bed to promote further ignition and heat generation to raise the temperature. Additionally, I envision the entire system being solar powered, because you might as well use the nice weather and sunlight while you are barbequing on a nice day. There will be a battery backup, in case of smoke or clouds.

More upgrades to the system for the future could be an audible alarm if the temperature drops too low, so that a new set of coals can be lit and added. A PID system could be added to control the fan or vent openings, however the complexities involved their may exceed the scope of this course. Additionally, a meat probe may be added to let you know exactly when you can dig in, though it’s application would not be compatible with some methods of smoking meats including mid cook foil wrapping.

Sketches¶

coming soon

Background¶

There are several DIY barbequers out there, since people who are willing to spend all day cooking meat also tend to not mind building their own stuff. Commercial products are available from several companies (in terms of digital thermometers with phone connectivity) from large companies such as Weber and Maverick, among others.

Other people have built their own temperature monitors {1, 2, 3, 4}, while some have even attempted an automated system to regulate temperature. The digital temperature sensors serve as an inspiration for the project, while the PID nature of the other systems seems like a project that, while interesting, is not as feasible for the setup I would be using. A bomb style smoker is better suited for the PID system shown, while the offset box is a more unpredictable system given the scale of the smoker. Also, all of the systems are directly connected, running wires around a hot grill, which is potentially a safety issue. I feel the remote application of the control to the fan would be a large improvement.

What I will Design¶

I will design the boards for use in the thermocouple system, LED output, and fan actuation. I will design storage cases for everything so it looks pretty, as well as the power system. I will also design and construct the housing of the fan assembly to ensure the generated airflow goes into the smoker box as desired. I have previously designed a solar charger for use with phones (5V, 1A output) that could be used to power the respective systems.

Materials and Components¶

I will require several microcontrollers, an LED output, one or 2 k-type thermocouples, a fan, the radio output and receiver, as well as the electrical components.

Source

Digikey for electrical components
Everything else can be found parts Cost
Solar chargers specced for less than $20 each (depending on volume of parts ordered)
K-Type Thermocouple probes are ~$10 each

Parts and Systems¶

There will be a few different modules in the system. There will be two power supplies connected to the units via usb. The thermometer unit will consist of the thermocouple, thermistor, LED screen, and radio frequency generator. The fan unit will have a receiver, fan, and attachment manifold to the smoker box.

Processes Used¶

The processes utilized in the system would be: - Electronics design - Electronics Production - Computer Controlled Cutting - 3D design - 3D Printing - Embedded Programming - Networking and Communication

Questions to be Answered¶

Some questions are: What will the display show? Do the temperature systems need to be calibrated? Will the board and microprocessor used allow additional space for mentioned upgrades? How much power will be required for the fan?

Evaluation of Project¶

The project can be evaluated based upon the accuracy of the temperature sensor, the display, and if the fan works or not. Locally, it can be evaluated by the deliciousness of the meats cooked with the system in place.