Like any project there is always alternatives that can be done. I had thought a lot about this project prior to starting. I was certainly trying to find out a way to make this project the most cost efficient and easy to build so basically anyone anywhere could reproduce it and be able to add on to it without any issues. With most of our projects I am sure I am not the only one that is guilty of this and that is over thinking everything. When I started I had tons of ideas and things that I wanted to implement but after realizing time and parts available it had to come down to what was doable and not what was imaginable. So even after the project is completed there is always going to be little things that can be done and that one could add on. Using the Raspberry Pi for a project like this is probably one of the best things that I could think of that makes the project. Reason being its versatility and ability to automate something so quickly and add on anything else you could possibly ever need with ease.
But like I have had spoken about prior was the many issues that I came across both hardware and software related. Now this is only a limitation due to time. Given more time and more parts you could really come up with some amazing units. I thought about it more and more and every part you add the more it costs so keeping things to a limitation was a great start in my design. Catching myself constantly trying to over do it when it came to the amount of feature and parts required. I have a ton of 3D printed parts that I had printed just in case I needed to further add on more items to the unit then they were there ready and waiting for me.
But this is all the fun of the design process finding out what works, what doesn't and what you would change after if you can.
When it came to finding alternatives I really was trying to think outside the box using what was available as I think they would in any situation in space. From what materials are available to them and looking to find out what in space I would use in the situation. Starting with the enclosure there is conduit of sorts hiding throughout the ISS and that was one of those things I thought would have been great to add to the unit. But afterwords finding out that the other rails that they had on the ISS would have been just as good and being able to make and design a 3D clamp on to the rails. But try finding hand rails from a space station at your local home depot. So hence the conduit version was born this was a great alternative.
When it comes to the actual materials for enclosing the unit there would be many items that would certainly fit the bill when it comes to building this in space. The first thing I thought of was the garbage bags that they use on the ISS the big ones you know looks like it belongs in video game like portal.
When it comes to the mounting of the hardware it wouldn't be that hard to have it all mount to a rail on the side of the unit. I went with the conduit once again as then I was able to remove the electrical panel and be able to do any work on the reverse side of the unit without any major issues. being able to make it look a lot cleaner on the inside visually was a nice bonus. I know that my wire management skill are not as pretty as they should be but this is something that can be addressed at a later time once everything is up and running.
When it came to the watering system there was so much that was left to be done always thinking of what would be the best solution for in space. I think the main thing that I kept thinking of is the flow of water. it would certainly need a more fuller container of water that one would have to keep topped up so that there was enough pressure for the pump to suck more water then any air in the unit.
The containers for growing were one of those things that in space having them sealed would make it so that there would be no ability to allow for any soil or waste to float into the air. But with my issue of not having enough soil to make the unit a fully enclosed unit was not as optimal. The soil shouldn't have any issues with staying together once it packed together and using the peat pucks further helps this being said a tighter mesh wrap around soil or basically finding a way to tap into a soil bag directly to run the water lines and everything would probably be the best solution depending on what you are growing. I would certainly like to give a few more examples of what could possibly be done with the soil enclosures for growing. There is a lot of options available that we can take advantage of and once again make things cheaper and quicker.
Making a kit that you could be small enough and light enough for travel and then setup taking no time at all is one of the many goals that I had thought of. Once again it comes down to what you have available and what you "think" you can make work. Since most of this is trial and error but being able to think out the process and eliminate things that wont work soon then later will hopefully help you with the process of getting everything up and running sooner then later.
This brings me to a point I want to make as much as we want to come up with the ultimate ideas for being able to grow in any situation, be on earth on a spaceship or another world its really hard to make anything more then a educated guess of the outcome of the process. I would have loved to been able to been able to test further in more situations. Having a system that would be able to quickly be adaptable to any environment is manageable but certainly more work involved in the full process.
I was however quite excited to find out that the lights that I had installed actually produced enough heat to keep the enclosure at a sustainable temperature throughout the day which prevents the heating system to come on during the daylight hours. This is a great savings in power consumption. I wasn't sure what to expect when the LED growing lights where installed what they would do. As I have used some LED Light strips in the past in projects but there wasn't as much heat being produced. That would bring me to a point if we were in hotter environment and required cooling we would have to assume the LED Lights would add a sufficient amount of heat that the cooling system would have to take into consideration and probably have to work harder. There would be more power consumption in this situation so more environment monitoring and solutions would have to be implemented.
When it comes down to it there is tons of things I would certainly want to change in the project and probably will do over time and try new things out but the main thing right now is making the current unit produced enough to start a harvest. With the unit working and being as automated as it can be I still have a few more things to add to the software to help monitor the system but this being said I think I want to start creating my own dashboard as the software has its limitations when using other peoples work when using it for something it was capable but not intended for. But it sure is a great job done by them but its not what I am calling the best solution for the application.
In the end I am sure that it will do the job, but I will say there is many things that one could do to make things a lot better. I have to say you can really take a deep dive into learning by this project as there is a ton of unknowns and options that would be available as well as the ability to adjust something for your situation finding the ultimate one method that regardless of placement is most certainly doable. But would require a much larger testing facility and resources. But the adventure here is using what is available to me mind you yes there was cost involved to me through the project but not as much as I thought it would be as I did try to make sure that I did everything as cheaply as I could.
If you have not figured it out by now....I am pretty darn cheap.
With that being said soil and electronics and filament are not free so finding the most cost efficient in each situation was on the top of my list reusing what I could from what I had laying around to ordering some questionable parts.
All 3d printed parts can be found here:
https://www.thingiverse.com/thing:4644039