TML 2020 #08: Building for the show – Improvements and Refinements
This journal is an entry in The Maker’s Lab journal series. Click here to read the previous entries.
For January and February, I worked on creating an improved version of the prototype Chiam (I will now be referring to the puppet as Chiam according to the script) after getting feedback from the jamming sessions. In a previous journal entry, I shared about some issues the prototype puppet faced:
- The entire structure was too heavy
- The puppet head looked too big and was not proportionate compared to the body
- The servo motors used for the chest mechanism were too loud
- The eye mechanism did not sit properly in the head structure
In the following journal entry, I will be covering the changes I made for the puppet.
Changes to Head Structure
For the new puppet, I used a different method to build the head. The base head shape was carved using styrofoam (Figure 1).
I wanted to make the head shape using papier mache like how masks are usually made. To achieve this, I will have to shape a skin layer using papier mache over the Styrofoam base. After peeling off that layer, I will then reinforce and stiffen the skin with more layers of papier mache. To build the papier mache skin layer over the styrofoam, I first tried covering the base with Vaseline so that the papier mache skin could come off easily. I found this method to be messy as the Vaseline stuck to the white glue and was difficult to handle with all the greasiness and stickiness. Over time, the Vaseline started to spread to the other layers of the papier mache which was not what I had intended. I then tried using cling wrap to cover the Vaseline instead of directly applying the papier mache onto the head. This still allows me to peel off the papier mache layer. Although this method required a lot more time and effort, it was much cleaner as the Vaseline and white glue were separated. I was able to preserve the original styrofoam base and make more duplicates of the head in the future.
I also added a 3-4 more layers of papier mache onto the face so that the structural integrity remains intact.
Modifications to eye mechanism
I included an extra servo motor for the eye mechanism. Using one servo motor for the up-down motion of the eye was not the most ideal as it added unnecessary stress to the servo motor during performance. I installed another servo motor to distribute the stress of the eye mechanism. The advantages of having 2 servo motors for separate eyes are:
- Movements of the eye mechanisms is cleaner and sharper (less inaccuracy)
- Mimics how a human would move their eyes.
However, the additional servo motor also meant the batteries would last shorter; hence require more frequent changes to the batteries. I felt the benefits outweigh the cons and believe that the additional servo motor will help achieve a more realistic eye movement. In this iteration, I have decided to separate the eye mechanism from the head. To achieve this, I constructed an aluminium frame that the eye mechanism can sit on, and later fitted it onto the papier mache head structure.
The reason for separating the eye mechanism from the head is so that I can troubleshoot the eye mechanism easily. This change will help me save a lot of time in the long run. The aluminium frame also strengthened the overall structure and acts as a housing for the eye mechanism and joystick.
In the previous prototype, I was given feedback from the puppeteer that the joystick sat too far from the head structure. This caused the puppeteer’s hand position to be further away from the pivoting point, adding stress to the wrist and increasing the weight of the puppet. Thus, I decided to build the joystick onto the back wooden structure that holds the aluminium rod. This small change increased the stability of the joystick (less wobbly) and is more ergonomic as it reduces the strain on the puppeteer and allows them to manoeuvre the eyes and head with ease.
I used recycled foam board to create the prototype and confirm the size of the eye structure before cutting the wood piece out.
Changes to Body and Chest mechanism
Prototype Chiam has a chest mechanism that pulls down the “diaphragm” with spring attached to the top, making the expanded area at the abdominal area of the puppet. For final Chiam, I inverted the whole, making the chest mechanism pull up the “diaphragm” instead of pulling down (see video 3). I wanted to replicate how the human chest expands by having the expanded area at the puppet’s chest.
I have also made changes to the proportions of the puppet. Prototype Chiam was extremely bulky and had a large torso and small arms. Final Chiam is more streamlined and has proportions similar to a human body. The flatter body and adjustments reduced a lot of weight for the puppeteers. I had to remove the battery packs on the puppet due to space constraints. This was a blessing in disguise as the weight of the puppet was further reduced.
The changes of the proportions also meant that the back support can no longer sit in the back of the torso. I was told that the position of the back support for prototype Chiam was too far from the thighs of the puppet. Therefore, for the final Chiam, I built the back support closer to the thighs. I took reference from the puppet-making masterclass conducted by Kian Sin and assisted by Daniel. Making a basic puppet without any modifications helped me understand how the positioning of rods, back support and handles on the “anatomy” of a puppet helps in manipulation.
Instead of making both vertical and horizontal cuts in the EVA foam for flexibility, we only made horizontal cuts in this iteration (Figure 26). The previous vertical and horizontal cuts compromised the integrity of the foam and weakened the shape too much. However, making only horizontal cuts retains the integrity of the EVA foam shape while allowing it to become more flexible. This then allows the EVA foam to expand and contract without weakening.
From the script, I tweaked the previous programme to now allow the puppet to enter a fast breathing mode after detecting stillness from the puppeteer for 18 seconds. We arrived at the timing of 18 seconds after rehearsing the puppet in the show. I initially had some issues changing the programming code as I could not get the Arduino counter to work in the desired manner. One reason was because the normal breathing mode was the default mode which the puppet starts with and so the tricky part was to find the right place to get the timer to start counting. I manage to sort it out by adding a condition to the code whereby the timer starts counting each time it is in normal mode after much trial and error and also after consulting Lin Xiang.
Changes to Limbs
I kept the arms of the puppet to the same dimensions but changed the way the EVA foam was shaped around the inner structure. However, I decided to redesign the legs to have a more standardized look between the arms, legs and the body structure.
Between the presentation of the creative concept and the making of the puppet, I was asked to think about why I chose the materials for the puppet. When it comes to the use of materials, I prioritised practicality over concept. I was asked what do the materials mean to the puppet and whether metal was considered a foreign material to the puppet? My original plan was to use metal joints for practicality but decided to do away with the metal joints after taking into consideration the concept I had, which was to keep the wood material for the puppet and metal / electronics for parts that were considered foreign to the puppet.
As for the joints, instead of using elastic band as per the arms, I decided to go ahead with using calico cloth reinforced by leukoplast tapes (Figure 29).
Making this joint was straightforward and less time-consuming compared to other wooden or metal joints. However, I discovered that it wears more easily and eventually final Chiam’s knee calico cloth joint fell apart halfway through the rehearsal in February.
The joint ripped apart in the middle of the rehearsal and I had to find a temporary reinforcement. Daniel suggested using a nylon strap for both sides of the joint before replacing the joint completely after the rehearsals.
I replaced the joint between two of the rehearsals and realised that I underestimated the time needed to make this change. After replacing the cloth joint with an aluminium plate, I found that the knee joint could not bend as much as the cloth joint. This was because the “flesh” of the legs was getting in the way of one another. Figures 34 to 37 below show the process of replacing the knee joint.
I realised that I had to increase the length of the wood pieces supporting the joint in order to increase the bending angle. I also used a 2mm aluminium strip (instead of 1mm initially) so that it could hold more weight.
With the new metal knee joint, it also resolved the issue of the knees wobbling from left to right. This was something that the puppeteer noticed as rehearsals went along due to the stretching of the cloth. Replacing both knee joints made them more stable and sustainable. This time, I had to focus on the practical and technical needs of the puppet.
Changes to Wearable
The wearable also underwent a lot of changes. The accelerometer is no longer mounted on the shoulder but on the electronics box containing the Arduino unit. I also replaced the battery holder to one with a casing and an on/off switch. As the puppet no longer has space for the battery pack, I had to mount the batteries on the puppeteers’ wearables and wire them to the chest. I also made changes to the servo motors. Prototype Chiam uses a MG996R but during the jamming sessions, the movement of the chest mechanism was really loud and interfered with the puppeteers’ and audience’s concentration. For final Chiam, I replaced it with DSSERVO DS3218MG. It has a higher torque power and also requires more power (4.8V to 6.8V) compared to MG996R (4V-6V). This meant I had to increase the number of batteries powering the servo motors (see Figure 38).
I also explored the use of retractable wires to connect the electronics to the puppet. The shop owner of one of the shops at Sim Lim mentioned that some are telephone cord wires and cannot be used for electronics. Out of curiosity, I asked an engineering friend and learnt that there are different types of wires like tinsel and copper wires. The type of wire will affect the maximum current that it can take. The retractable wires that I bought uses copper wires which is sufficient for my purposes. As there is a lot of movement from the puppeteers, the wires get tugged very easily. The retractable wires allow the puppeteers to move around and at the same time retract to its original length, giving them some allowance to move around without the need for me to have long dangling wires.
The soldering of the accelerometer to the PCB board was especially challenging. The soldering had to be redone multiple times as the Arduino could not read the data collected by the accelerometer. After several tries, I learnt that:
- having the soldering done as cleanly as possible without cross contamination between wires and
- removing oil from the solder helps to prevent errors from happening.
Costumes and Finishing
I had difficulties attempting to find the appropriate costumes for Chiam. My costume design for Chiam is inspired by uncles in the 60s and 70s. Initially, I wanted him to have a white T-shirt or singlet together with khaki shorts.
However, with the requirements from the script that the puppet’s shirt needs to be removed to reveal the chest mechanism, the T-shirt or singlet (which is removed from the top) became unfeasible. Therefore, I had to use a button down shirt so that the puppeteers could easily remove the top. It was difficult to find similar costumes in the children’s section. I found out that some puppet makers usually go to the children’s section to shop for clothes. Myra kindly shared that she usually goes to Mustafa to find clothes in the children’s section. Chiam’s top was found in the toddler’s section but was a little too big and I had to get Abital, my assistant maker, to help with altering the top. Abital also helped to make the pants and Cher See helped to make the sandals from scratch.
In the final phase, I had three assistant makers, Abital, Marilyn and Cher See to assist me. I found that it is important to understand the assistants’ strengths and where to get help with. Some were better in woodworking, others electronics or costume-making. I also got to learn a lot from the assistants and their expertise in making.
For the finishing of the puppet (which I am still working on), I learnt that artists usually paint the undertone on the puppet first before applying the skin tone (see Figure 43).
Chiam’s sandals were inspired by sandals that some Singaporean uncles wear around. As I could not find similar children sandals, this had to be created from scratch. The sandals were created from wood and EVA foam. I wanted to keep the materials the same as the other parts of the puppet.
The corners of the straps had to be reinforced with boning structure as it was a little weak.
Over the course of the rehearsals, I had to make several amendments to the design and structure of the puppet. I hope to cover these changes made in my next journal entry.
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 firstname.lastname@example.org.
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