Week-16 System integration
This is my 16 week at FabAcademy. This week we needed to work on the integration of our final project. The assignment of the week is as follows:
- Design and document the system integration for your final project
‘Heroshot: My designed and fabricated PCB box and servos covers and elongations’
Integration that I face in my project: all components of the system
In the following image I illustrate all the components of my system:
So my challenge was integrating all those components in the best possible way. In the following sections I explain all the integrations works I did to achieve it.
PCB box cover and servo arm & body cover
Based on the electronic components of my design, see the list of componentes in the Midterm Review I designed in this week all necessary for integrating the components my autonomous wall prototype.
First of all I started working in my PCB (below I gave all the details of the PCB as well as the corresponding design and fabrication files). In summary, I will need to put external wiring for connecting an ambient light input sensor, 2 temperature input sensors, power wiring, and 2 output servos. In addition, I decided that the best choice would be to integrate the OLED screen in the PCB box because I experienced a similar design in a previous week (see details here Mechanical Design) and I think that could work very well in my case. The idea is that someone can see the ambient and inner temperature when looking at the side of the wall element. Therefore, first of all, I started designing in Grasshopper my box and used as inspiration the top cover of the box shared by RajPShinde for a camera slider, see his repository at https://github.com/RajPShinde/CamSlider, which is licensed under GPL-3.0 license. After importing this as a solid volume, I just started measuring my PCB and in particular the location of the different pins. After measuring the PCB I defined the overall size of the box as well as included 4 pins of for 3mm bolts and 2 fixing flanges, here you can see an image of the parametric design, you can see all the details of each operation in the Grasshopper file, which can be download in the last part of this website:
Once defined the main structure of the box, I imported as solid the OLED container of RajPShinde, you can see here what I imported from the other model:
Then I included this in my own box top by simple operations:
Finally, I defined the holes required for wiring, and substracted the corresponding volumes by boolean operations. The holes where done of about 1 cm in height, which I considered enough for the wiring. Here you can see the mesh of the resultin stl file
That I subsequently used for printing in our prusa MK3 printer. I used brown 1.5 mm filament available in our lab to achieve the maximum possible aesthetic integration of the box with the wood, here you can see the result after printing:
Once the box was printed I started fabricating a cover box for the servo that could allow for integration and fixing of the servos into my wood chords of the wall panel. Also after doing some testing I realized that I would need to design and fabricate a servo arm elongation becuase the deafult arm was not large enough for allowing proper opening/closing of the ventilation gates of the wall.
Regarding the servo box, firstly I downloaded an open model of my servo available at thingiverse. The model has been shared by lylesvendsen and is available at https://www.thingiverse.com/thing:2641076#google_vignette under Creative Commons - Attribution - Share Alike.
As for the PCB Box, firstly I imported the model of the servo as volume:
Then I created a bounding volume and applied solid difference:
Next, as for the PCB box I created a hole for the wiring:
Then, I created two flanges with their corresponding screwing holes for connecting with the timber:
You can download the Grasshopper file and stl file in the download section.
Regarding the arm, I essentially measured with a caliper the 2 archs and lenghts defining the arm that comes by deafult with the servo of my inventory:
Then extruded it:
Scaled it to a surroundinmg and longer one and applied solid difference:
Here you can see the result of the integration of all designed and fabricated pieces including already the wiring of the elments.
You can see further details of the wiring and mounting process here Project Development.
Regarding the wiring itself, I decided to use a flexible cover bought at amazon and intended to organize wiring. You can see further details of the wiring cover at Amazon. Then I fixed the wiring cover to the wood with conventional double sided tape that we had available in our lab:
Foam profiles for enhancing air tightness
After doing some tests during the final project development, I realized that a weak point of my project was that it was hard to assure the air-tightness of the components, even when they all were digitally designed and manufactured. Therefore, during the assignment of week 17 I decided to design and fabricate foam profiles for attaching at the edges of the metacrylate ventilation gates, enhancing thus the entire integration of my system. The design and fabrication process is explained with full details in week 17, so here I only present the resulting foam profiles, and the working process for integrating those in my system. The foam profiles I designed and fabricated look like this:
After fabricating it, I realized that if I just put the foam profiles in the metacrylate it will be raised by about 3 mm from its original position, therefore generating an air cavity that drops the possibility of air-tightness. Thus, I measured the size of the hinges and first cut by laser several rectangles of wood panel to make a perfect fit as base for the hinges. Here you can see the result:
Once that was done, I started gluing the foam on the metacrylate, here you can see the set up I used for the gluing:
I did some mistakes and need to wash the metacrylate….
Buf finally I got those pofiles glued and integrated in my system, improving the air-tightness and overall integration of components:
UPDATE OF THE WIRING INTEGRATION
After the project presentations, Neil advised my to improve the wiring of my system. Therfore I completely re made the wiring with the objective of maximize integration and avoid visible wiring. For doing that….
Files for download and replication
Here you can download the Grasshopper and .stl files of the my PCB_Box_Design as well as the cover and arm elongation of the servo Servo_cover_&_elongation.
Here you can download the profiles of foam: foam profiles