Structural Refinements and New Explorations

by fingerplayers

Daniel: We are now three months into Xin Feng’s exploration in The Maker’s Lab. In the previous few weeks, Xin Feng has built several prototypes of the eye mechanism, tinkered with Arduino and circuitry, researched into possibilities of animatronics and grappled with the reasons, ethics and implications of incorporating animatronics into puppetry. It is important to also acknowledge that the journey of a maker and designer is not just technical. There is always the self-doubt and uncertainty of whether a new idea will even work, or whether your construction skills are sufficient to turn a design into a working prototype. That then perhaps turns into blind faith or self-denial for a while and then into frustration when even at the end, you have still just built a prototype with flaws and improvements to be made.

At this stage in The Maker’s Lab (TML), we have had our first creative meeting with Myra and Ellison, collaborators who will be creating a work emerging from Xin Feng’s design. Intriguingly, we discussed ideas of whether animatronics can expand the possibilities of puppeteering, allowing the puppeteer to both consciously and subconsciously manipulate a puppet. How can the puppeteer gain more flexibility in manipulating? What if the puppet’s expression is dependent on a subconscious aspect of the puppeteer’s body? Is the puppeteer entirely in control of the puppet, and what happens when the puppeteer is not?

Structural Refinements to the Eye Mechanism

Xin Feng: The main objective for August was to create a working eye mechanism with a more refined base.

Through the previous prototypes, it was found that:

  • Servo arms were not aligned with the holes of the ping pong ball and that causes complications when connecting the servo arms to the ping pong ball
  • Metal wire connecting the ping pong ball to servo motors had started to rust which makes the metal wire not viable as a long-term material for the eye mechanism 
  • Basswood was not the most ideal material to work with as it breaks easily when cutting

Additional pointers to consider in refining prototype:

  • Reducing weight of the base to try to lighten the weight of the entire mechanism
    • Through changing the type of wood used
    • Adjustments to the amount of materials used
  • Searching for the most suitable and easily available material used for various parts of the eye mechanism
  • Working out the electronics
    • Through tidying up the circuitry and soldering wires to make connections more stable
    • Working on the programming of the Arduino commands

#1: Refining Part 1

For more consistency and accuracy in the making of the base plate, a digitised 1:1 template was created. This was spray-mounted onto the wood materials and cut accordingly, using the band saw (Figure 1).

Figure 1: 1:1 printed template spray-mounted onto the wood
Figure 2: Digital template of the entire structure

An issue that came up from the previous prototype was the misalignment of the back servo motors’ arms that controlled the up-down movement of the ping pong ball. Previously, the up-down servo motors were stuck on with tape. Housing for the back servos were added for better alignment (Figure 3).

Figure 3: Building the housing for the back servos

Figure 4 shows the finished prototype (left). The arms of the back servos still faced some alignment issues.

Figure 4: Current prototype (left) in comparison to the previous prototype

#2: Refining Part 2

Figure 5 shows the improved template of the base plate. To reduce the weight, amount of materials used and number of connecting parts, the part highlighted in yellow would now be part of the same plane.

Figure 5: Improved template of base plate

While building the base plate, it was noted that using basswood as the base material was not the best choice. Parts of the wood frayed and weakened during the process of using the band saw as well as the drill press. See figure 6 and 7.

Figure 6: Chipping of wood
Figure 7: Cracking of wood while cutting

Another issue to be resolved was the alignment of the up-down servo motors’ arms. The default plastic arms are not long enough to allow the wires to be perpendicularly attached to the eyeball. As such, I had to make extensions using aluminium strips. I had to re-build them a few times as the holes were not aligned. To help with the alignment, an awl was used to mark the positions for the holes. This helped the drill bit to stay in position to create a precise hole.

Figure 8: Arm extension attempts

It was also noted that the metal wire thread originally used to connect the ping pong balls to the servo motors had started showing significant amount of rusting. This wire thread was purchased from Art Friend and is usually used for jewellery, but is useful in this application as a very fine but stiff material to connect the servo arms to the ping pong balls. With the rusting though, it becomes not viable as we will then need to keep changing them out as the rust will obstruct the functioning of the wires.

Figure 9: Rusting of wire thread

Fishing line was therefore used to replace the metal wires. Figure 10 shows the fishing line connecting the ping pong ball to the back servo motor. Because the left-right servo motor was in the way of the bottom fishing line, a rubber tubing was used to route the line to facilitate the up-down movement of the ping pong ball.

Figure 10: Rubber tubing used to re-route the bottom fishing line

Plywood was later used as an alternative for the base. Figure 11 shows the near-complete base plate using the improved template.

Figure 11: Near-complete base plate

Some minor adjustments had to be made to the base plate holding the dowel supporting the ping pong ball to create a more secure holder (Figure 12).

#3: Refining Part 3

The coding and wiring of the mechanism was the final focus of the refinements.

Figure 12: Changes made to base plate to align the strings

The previous configuration of the wiring (as seen in Figure 13) was really chaotic, making troubleshooting extremely difficult. Figure 14 shows the improved version of the wiring. Some jumper wires had been replaced with flat wires.

Figure 13: Initial use of jumper cables during prototyping

The previous configuration of the wiring (as seen in Figure 13) was really chaotic, making troubleshooting extremely difficult. Figure 14 shows the improved version of the wiring. Some jumper wires had been replaced with flat wires.

Figure 14: Tidied up cables

This will not be the last refinement, as the current configuration is still a little bulky.

Further Refinements

While visiting Sim Lim Tower, a staff at Amicus Engineering shared that the breadboard can be replaced with PCB Board and the Arduino UNO be replaced with an Arduino Nano. These will be things to explore in the coming weeks, in an attempt to reduce size and weight of the eye mechanism so as to lighten the load on the puppet’s head.

Result of the Refinements

Video 1: Latest Prototype

More things to work on

In the upcoming weeks, I will be working on the following:

  • Power on the eye mechanism
  • Testing with remote control
  • Testing with joystick, Arduino Nano & PCB Board

Conceptualising the Second Mechanism

In the earlier stages of The Maker’s Lab, three focal areas were shortlisted based on the important focal areas of puppeteering:

  • Eye Focus
  • Breath
  • Movement

Why Joints & Movement?

I decided to focus on the aspect of movement after attending The Maker’s Assembly at the beginning of August on “Joints”. The workshop made me curious about the role of joints in creating movement. During the joint workshop, there was emphasis on precision in making joints. One of the joints that was a little shaky was put aside and considered “not as good”. This made me wonder how such “mistakes” in joints can be made on purpose to create certain specific movements in a puppet, such as a puppet with Parkinson’s.

In a human, joints are an important aspect in daily life. Joints help a person move better and can tell a lot about a person’s health. For example, someone with knee problems would move slower. Someone who is obese may have knee problems in old age, due to the pressure placed upon the knee joints. Bad posture can also lead to unnecessary knee pains.

While researching on injuries and pains in puppeteering, I came across Mary Robinette Kowal’s blog ( on “good pains” and “bad pains” in puppeteering.

A quick summary of my understanding or good and bad pains from her blog:

  • How to differentiate good pain and bad pain
    • Good Pain
      When Puppeteering, you need a certain amount of tension to deliver a movement (similar to the actor’s body)
    • Bad Pain
      When you overstretch yourself, and you hear a crack/pop but you ignore it

This led me to an article on how puppeteers have used exoskeletons in taking strain off their puppeteering process (

I feel that there is not enough research and focus on this area of ergonomically designed puppets. In this second part of the lab, I wish to find out how to solve existing problems in puppeteering through ergonomics, with focus on joints.

Through my interviews with puppeteers in the earlier part of my research, I found that learning to build stamina and muscle strength has been an ongoing process for every actor/puppeteer. This made me wonder if there are ways to ease the puppeteering process. Could there be ergonomically-built puppets? How can mechanisms help to ease this?

Passive Manipulation

I have been very interested in the use of sensors within animatronics in puppetry. In a discussion with Daniel, Ellison and Myra, they prompted me to think further about the use of sensors and animatronics to extend a puppeteer’s manipulation beyond that of intentional and directed manipulation. The term “passive manipulation” came up as a means to consider the possibility of subconscious actions or bodily conditions (posture, breath, heart rate, etc) as a type of manipulation. Passive manipulation highlights and puts emphasis on the constant feedback loop between the puppet and puppeteer.

I am particularly inspired by a performance artist by the name of Stelarc ( who frequently explores similar concepts in his works. He usually wires himself up to electronics and allows his body to be “controlled” by the robotic extension. In his most recent performance, Reclining Stickman (, he attaches himself to a 9m robot and controls some aspects of the movement. However, anyone around the world can access the interface and control the robot, which in turn controls Stelarc. As an audience, one then question who is truly in control of the robot?

Moving ahead

I am still in the midst of researching this area and will share more thoughts / findings in my following entries.

Can the use of technology in animatronics reduce the number of puppeteers needed to manipulate the puppet? Perhaps through reading certain body movements of the puppeteer, the mechanism in the puppet is sent a signal, triggering a series of movements in the puppet. Therefore, reducing number of puppeteers required.

While researching, I found this eBook with various research articles on the topic of 21st Century Puppetry.

Good for further reading.

This article is a monthly reflection by Sim Xin Feng, the maker of our inaugural The Maker’s Lab as part of an ongoing 9-month experimental laboratory. The Maker’s Lab is curated and managed by Daniel Sim, a core team member of TFP. The ideas and reflections within the article are drawn from Xin Feng’s observations and discoveries as a maker, designer and researcher. Instead of being taken as conclusive, we hope that they serve to be a starting point for thought-provoking conversations and perhaps even debates. We would love to hear from you and can be reached at You can also share with your comments below.

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