Introduction: Back to the Future Mind Reading Hat
I have a scientific background and since I remember I was into sci-fi too. Few years ago, I have discovered another passion which is 3D printing. With time I have learnt to design and build my own printers and then I started to learn CAD design. Couple years ago I found out about Fusion 360 and I fall in love instantly. I'm still a beginner and I have a lot to learn, but Fusion 360 allowed me to recreate props from my favorite movies.
In this instructables I will show you how I designed and 3D printed mind reading helmet from classic sci-fi trilogy 'Back to the Future'
Supplies
- PLA
- 2m x 10mm OD perspex tube (3D printed alternative available)
- Arduino Nano
- 13 x 5mm White LED's
- 13 x 220 Ohm 0.5W resistors
- 9V battery
- 9V battery clip
- On/off slide switch
- Red wire (1mm to 3mm thick)
- Grey wire (5mm to 8mm thick)
- Equipment wire
- Cable ties
- Super glue (I recommend gorilla glue)
- Solder
Tools:
- 3d Printer
- Soldering iron
- Screwdriver
Software:
- Arduino IDE
- Cura (or any other slicing software)
Step 1: Design Part 1
I have started the design from the coils and cylinders which are quite straight forward to design, but I come across few issues. The original helmet have transparent pieces and at the moment you can't print them on FDM printers. I have decided to incorporate clear perspex tubes (10mm OD and 90mm long).
If you do not wish to mess with perspex, you can use an alternative and 3D print this part, preferably in clear PLA.
As you can see I have designed the coils (red and grey), but I also decided to wind real wire instead. You can 3D print them as an alternative too, but then you will have to paint the coils - the choice is yours.
On the pictures above you can see in what order all the parts should be assembled.
Step 2: Design Part 2
The next step was to design connectors with specific shape to join the cylindrical parts made in previous step. I have created a headband and then I have arranged all cylinders similarly to the original helmet from the movie. After that I had to design few different connectors (length and shape) to connect all the parts together.
When I finished the helmet started to look like the one from the movie, but I'm always trying to add something as I'm not a fan of perfect copies. I decided to add the LED's inside the cylinders and control them with Arduino nano. Adding all the wires, LED's and resistors made it look more 'realistic' plus you can program different patterns for LED's. I even recommend to use RGB LED's which will give you more freedom over the colours you wish to display in the helmet.
Step 3: Assembly Part 1
Below you will find all STL files and, in the name of each file, I have included the number of the parts you need to print, and also the colour of the connector which corresponds to the map above.
After printing, I recommend to assemble all the coils with perspex rod (or 3D printed alternative) and then begin to connect them starting from blue connector. Use superglue and make the initial ring (blue) and leave for 5-8 hours for glue to cure properly.
Then glue the orange and purple connectors, making a dome like structure and then leave it for another 5-8 hours. Finally glue the red and green connectors.
UPDATE: Someone requested to cut headband files in half and I just uploaded the new files. Headband_v2_splited.stl is split in half and Headband_v3_splited.stl is split into 4 pieces.
Attachments
clear_cylinder_x13.stl
connector_blue_x8.stl
connector_green_4.stl
headband_2.stl
inside_cylinder_x13.stl
main_coil_x13.stl
headband_1.stl
ouside_cylinder_x13.stl
perspex_tube_coil_alternative.stl
screw.stl
connector_yellow_x4.stl
connector_green_4_v2_flat.stl
connector_pink_x4.stl
connector_red_x8.stl
perspex_tube_x13.stl
main_coil_alternative.stl
headband_v2_splited.stl
headband_v3_splited.stl
Step 4: Assembly Part 2
Here you have a diagram for wiring the LED's. You will also find STL files to print box for the electronics (arduino and battery) which you can attach to your belt for example.
If you wish to learn more about uploading Arduino code and setting up STL files for printing, please visit one of my other Instructables:
https://www.instructables.com/id/Self-Calibrating-...
The code is quite simple. The LED will light up randomly for random amount of time. You can, of course, temper with the code and change it to your needs, especially if you decide to use RGB LED's.
Step 5: Assembly Part 3
Here are the pictures of assembled helmet. As you can see, I have decided to use 10mm clear perspex tubes, and I have also used red and grey wire to wind the coils instead of printing and painting them.
All the cables from LED's I have wrapped around the connectors and then secured with clear cable ties.
I have left about 1.5m long cable from each LED. All of them go into 3D printed box which I can clip to my belt.
I'm not going to lie to you, it's not easy project, but for a massive geek and movie fan like me, it was totally worth to do it. On the 3D model all parts fit perfectly but, as many of you know, FDM printer are not super accurate and, if your printer isn't perfectly calibrated, some parts might not fit. For those who are new in 3D printing, you can use hair dryer to warm up the plastic part and then reshape it slightly to make a perfect fit.
Step 6: Comic Con Time
When I finally finished my helmet, I went to Comic Con dressed up as Doc Brown. Unfortunately, I quote:
'This damn thing doesn't work at all'
I hope you will enjoy this project :)

Runner Up in the
3D Printed Contest
17 Comments
1 year ago
Do you know what this means?
Reply 1 year ago
That this damn thing doesn't work at all :D
3 years ago
Hahaha! Yo, Doc! Great job :D
3 years ago
Love Back to the Future. Great Job!
Reply 3 years ago
Cura does not allow the split headband to slice. Can you put one quarter in each file instead of all four in one?
Reply 3 years ago
Hi, will do tomorrow. Can you let me know which version of Cura you are using? I'm using old one and it can split models. Try to right mouse click on the model loaded in Cura and then there should be option to 'Split object into parts'. If you won't be able to do that I will upload separate files tomorrow morning :)
Question 3 years ago on Step 3
Thank you so much for listing this. It looks like you did an amazing job. I have a question about headband 1. I have a Prusa 3i printer. The headband won't fit on the bed. Is there a way to print it in 2 pieces and glue it together? I wouldn't know how to slice it into 2 parts. All suggestions would be appreciated. Thank you in advance.
Answer 3 years ago
Hi, I will cut in half for you and upload the files within next 24 hours. In the future I would recommend using Sli3er (https://slic3r.org/download/) Usually I'm using Cura but Sli3er has one really cool feature, you can cut stl as you like. I'm using it very often and the slicer itself is free :) I hope that helps
Reply 3 years ago
I'm old. I'm just happy that I figured out how to use Cura ! Thanks for cutting the headband in half for me and helping me with this. I appreciate it.
Reply 3 years ago
Hi, I just uploaded headband cut in half and into 4 pieces. I hope that helps and if you will need anything else just message me :)
Reply 3 years ago
Where do I access the .stl file? I don't see it here. Thanks!
Reply 3 years ago
I just check on my wife profile and to see new stl files you must refresh Instructables website. When you open it again, press F5 on keyboard to refresh and then you should see new stl files which will be at the bottom of Step 3
Reply 3 years ago
All stl files are in Step 3 below pictures and text. Just before Step 4. You should see white blank icons with the file names and download button next to them. After that you will see Step 4.
3 years ago
LOVE the trilogy, absolutely brilliant!
3 years ago
Hilarious! And such a fashion statement.
3 years ago
Love it! : )
Reply 3 years ago
Thank you :)