A Cooking Machine - Assembly

This post is the tenth in a series detailing the processes behind the research, design, material selection, online audience building, fundraising, application development, assembly, and programming of a cooking machine. See the column Stories of Food & Tech here.

This post discusses my journey of testing and assembling my first smart cooking machine. During the process, I realized that there are many mismatched components that currently prevent me from building a full running cooking machine. However, in this post I  provide a quick overview and test some of the working components.

Part I: Component Overview 

Whenever the yellow light started flashing on my Echo dot (a voice-controlled smart speaker), my heart would get excited because it signaled another one of my packages containing a component  had arrived. One by one, these packages began arriving from all over the world (especially China where the cheapest electronics are produced). 

Image 1.1 Hardware & Electronics for my cooking machine (not including spare parts or electronic tools for assembly) 

Image 1.2

Hardware & Electronics for my cooking machine - Induction Cooker

Since this process began, I have ordered and received 80% of my main components, and I’m quite satisfied with the components’ qualities. However, as I started unpacking these deliveries, small parts such as liquid pump tubes, batteries, and jumper wires were not included in the main components I bought, even though the seller posted a picture containing these small parts. 

“OHH, NO!” I thought to myself, “Now I need to spend additional time getting additional small parts; hopefully, they arrive soon so that I can start the testing processes.” After another round of online purchasing, I finally received enough parts to start testing. 

Through the past few weeks, I compiled this 1-minute video, which gives an overview of the various components in my machine:

Video of the testing processes: link

Part II: Testing Component Functionality 

Below, l also discuss two components in more detail to illustrate my testing processes:

1-    Testing the Stepper Motor:

Image 2. Stepper Motor Setup

Stepper motors can move at a customized speed continuously through a motor driver (the H-Bridge), both clockwise and counter-clockwise. Image 2 above shows the circuit built for enabling these stepper motor functions. The H-bridge was connected to an Arduino micro-controller and allowed me to customize the speed, direction, and motor control of the motor itself.

Image 3.

Motor testing Circuit & Wiring

During the motor testing, I went through the motor’s datasheet and circuit design and realized that without the motor driver and a basic Arduino microcontroller I could not move forward. So, I did another round of online purchasing to get needed electronic parts and tools. Since most of these parts sell in bulk, I got many spare parts that won’t be useful for now. “Maybe I’ll just use them if I decide to build another cooking machine in the future,” I thought to myself, as I made peace with the fact that there are always unknowns when building an engineering product. 

1-    Drilling holes on glass:

A second major testing process was learning to drill holes into glass. To insert the pot-stirrer and tubes for pumping oil/water into the pot, I need to drill three holes on the pot lid, which in my case, is made of glass and has a slight curvature. I had no clue how to drill into glass, but I knew a few people who might. So as a result, I went to MITERS, an on-campus maker space for engineers, to get some advice and brainstorm some approaches. Eventually, we came up with either using a waterjet, which is insanely expensive, or buying a cheap diamond drill bit and drill a hole on top.

Image 4.

First Test Run of Drilling Holes on Glass

Image 4 above shows the first hole I drilled on the back of a glass bottle as a way of practicing drilling holes on glass. It was a bit intimidating at first because the glass bottle didn’t stabilize well, so I needed to hold the bottle tightly and press it down with my hands while drilling. However, after a few practice, I felt much more comfortable with this process and proud of myself that I learned this skill.  

Conclusion and Next Steps

As with any technical project, the assembly and testing phase of this project is revealing a lot of unplanned technical issues and new (exciting) hurdles that I need to overcome. Apart from waiting for a few components to arrive in the next few weeks to assist in further testing, I also potentially want to swap out some existing components. These components include the pot with the lid, the liquid pump tube, motor housing, and potentially the motor itself. The reasons are: 1) the pot is a bit small in terms of cooking an actual meal, 2) the liquid pump tube is not food safe,  3) the house for the motor, which controls the stirrer, is from an off-the-shelf manufacturer and doesn’t allow customization, and 4) the motor torque might not be enough (still need testing). I am also thinking of re-designing the motor housing myself instead of purchasing one online.  

Aside from these hurdles, I can safely say that although these technical issues are inevitable, I am pretty excited about trying the many new components and adapting them to the rapid development changes of my cooking machine. 

For the next post, I will completely assemble the cooking machine and share the complete machine testing experience. I’ll also keep you updated on the testing of the new components that arrive in the next few weeks. Stay tuned :)