Ever since I was a small child, I always loved figures. 1:6 scale action figures of Barbie, Ken, Action Man and Batman, to smaller 1:12 scale figures of Spiderman and local Australian football players, I always enjoyed receiving them from my family.

As I grew, the love for these figures never changed, however the subjects did. As I progressed into my teens, my attention changed to cheap PVC figures you would find in gatcha machines and arcades, to posable 1:12 figures of characters from Japanese Animations, to figures from Good-Smile Company and then, as I aged into adulthood, to high quality figures from the likes of Alter.

Recent I decided to study different forms of articulation found in standard action figures in order to better understand and have the opportunity to 3D print some myself in the future.
Surprisingly there was less information about different types of joints online that I had expected. Hasbro Toy Designer Paul Bennett was featured as a guest at the 2019 Pixologic zBrush Summit and during his lecture, he briefly talked about the different types of articulation found in Hasbro action figures.

The lecture is fascinating and I highly recommend watching it if you have the time.

Below is a quick introduction to various areas of articulation. These are useful when 3D modelling.

A Ball Disk Joint allows for a 45° to 60° movement forward and backwards, where a Snap-On Ball Joint allows for full 360° movement depending on the size of the head.

Butterfly Shoulder joints allow for full 360° horizontal movement of the arms joints. The Double Barbell Hip Joint allows for easy attachment of legs and provide 45° to 180° movements depending on the design of the hips area.

Chest joints are self-explanatory. A Single Barbell Joint provides a large degree of movement from the centre of the chest. The advantage of a Barbell joint is that you can move side to side. A U-hinge/T-Hinge Joint allows for a very limited range of movement, but is cheaper and more sturdy of the two chest joints.

A Flat-Plane Joint allows for full 360° movement between the hips and chest. A single-disk joint allows for a varying degrees of movement depending on how the joint is fitted in the limb.

A Single-Pin Joint connects two full limb sections together. While the degree of movement varies depending on the model itself, it can provide up to 100° of movement forward and backward. A Double-Pin Joint gives a wider array of movement, providing up to 180° depending on the joint.

There are more intricate types of joints and articulation that can provide a more flexible frame, such as those found in Ball Jointed Dolls. While older dolls used a series of pullies and strings to move around, newer dolls use plastic ball joints to form the base skeleton. A good example of these skeletons are those found in the Dollfie or Smart Doll brand. Putting together the joints covered in this post today provide a basic skeleton on which you can model a basic action figure.

Back in January 2020, during the weekend of LoveLive Fes at Saitama Super Arena, I was struck with the idea of constructing the mask of one of the characters, Tennoji Rina, of the idol group Nijigasaki School Idol Club. It would make for a great cosplay set piece and a fun challenge to construct.

According to character lore, the mask itself, called the “Automatic Emotion Conversion Rina-chan Board”[ オートエモーションコンバート璃奈ちゃんボード] was developed by the computer department of the fictional school in order to assist Rina in expressing emotion. It is theorised that she is on the spectrum and struggles to express emotion, and thus the mask was born to help her do so.

During that cold weekend in the middle of January, Tanaka Chiemi, the actress who plays the role of Rina, entered the stage at Super Arena wearing the mask, and it was impressive.

It was very well polished, with what appeared to be frosted Perspex plastic on the front face to hide the LEDs behind. Obviously, without the support of a large conglomerate to fund my exploits, I would have to rely on the knowledge and ability I have, while researching new methods. Frosted Perspex could be an option for hiding any grid line the LEDs may create.

While researching and sketching up initial designs, I ran into an acquaintance who just so happened to have the same idea, but was already leagues ahead of me. While I really wanted to design my own mask from the beginning (It’s exciting!), I knew that the time spent could be used on other projects, so I reached out to my friend and they were more than happy to share their current work with me.

While discussing electronic configuration, Arduino code, LED setups and programming, we both discovered that a Japanese fan had already engineered his own mask and provided the mock up designs for the electronics on a handy blog post. He also had created a video on YouTube, displaying his work.

Requirements - https://qiita.com/hamahamabe/items/9216df345bb908eb5199

Design - https://qiita.com/hamahamabe/items/f2a5497aea395eb9699d

Programing - https://qiita.com/hamahamabe/items/6612540a72b915410b99

For someone who claimed they were an absolute beginner at 3D printing, design and soldering, Hamato did an excellent job and is a great example of accomplishing great things when you put your mind to it. There are some improvements that could be made to the electronic, such as

Hamato didn’t provide 3D designs (for good, legal reasons), but did provide great notes on LEDs with measurements included for the front face. With this information, it was easy to mock up potential faces on grid paper.

Hamato recommended these LED strips for the face in his blog posts, so rather than reinvent the wheel, I’ll make the trip over to Akihabara for these.

https://www.akiba-led.jp/product/1772

Finally, here are some pictures of the 3D parts to be printed on an FDM printer. Some parts are almost 200mm large, taking up all the space of a standard, run of the mill FDM 3D printer.

-=Parts List to be acquired=-

Arduino Nano (preferably Arduino Due for scalability)

3 x Switches (at least)

5V1A Battery Pack (at least) (Nano/Uno cannot go higher than 5.5V)

NeoPixel 2020 Extra Fine Tape LED 1m / 120LED [ 9779 ]

Breadboard Jumper Kit (for good measure and testing)

Transistors

Stay tuned for the next post. Up next is 3D Printing!

For legal reasons, these 3D models will not be available to download.

Due to currently only having immediate access to an SLA 3D Printer, this project has been put on hold for the time being until a suitable FDM 3D Printer is acquired.