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CTEC607 #16

Once Arduino received the signal from the encoder, Stefan and I used the readings to calculate a velocity (direction and speed). I sent this information as serial to Processing.

In my first iteration within Processing, I set up a program using processing video library to loop video. The video library allows playback speed to be controlled. It is supposed to be capable of reversing video also, however myself and many other processing users have difficulty employing this functionality.

In my second iteration, I used After Effects to create a reversed copy of the loop. The forward and backward loops play simultaneously, and processing switches based on the received serial from Arduino.

In my third iteration, I made the tracked time of the backwards loop inversely proportionate to the forwards loop. This way the loop always played seamlessly regardless of direction or when the direction changed.

Overall, I am very happy with the code efficiency, however Processing does not handle large video (or any video) elegantly. Regardless of the resolution and framerate of the film, it outputs with heavy stutter and bad framerate. I managed to curtail this by reducing the resolution and framerate from the intended 1080p at 60fps to 360p at 30fps. The final output was unfortunately quite stuttery, but given the closeness to open studio, we elected to leave it in it current state.

In hindsight, I feel that either preloading the videos in processing through an add-on, or using a different application would be prudent.

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CTEC607 #15

After the gears were in place, I mounted the encoder. To do this I glued the encoder to a wooden packer, and screwed the packer to the channels milled on the steel baseplate. I sanded the wooden packer before dry fitting multiple times to ensure the sensors and the code wheel band lined up.

Following this, I soldered wires to headers for use with an Arduino Uno. The encoder did not work. I was particularly worried that the sensor may have been faulty. In hindsight, I should have confirmed that the encoder was functional before fabricating the mechanism. I sent an email to Stefan explaining the current state of the encoder, and the troubleshooting I had done.

With assistance from Stefan, we managed to get the sensor module to send serial - the module PCB was printed upside down, with identification of the wires backwards.

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Printing the gears.

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CTEC607 #14

The gears printed perfectly, and fit over the recorder dish pin and encoder pin perfectly. Both pins had been previously splined, and the printed gears bound on the splines, acting as stoppers to prevent play and slippage.

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CTEC607 #13

I spent the evening researching how to properly design spur gears. Fusion proved really useful, as there is a script which automatically models gears based on input parameters. I sketched up the gears I needed to make, with the required pitch diameter. To make the gears transfer rotation at a 1:1 ratio, the gears had to have the same pitch diameter.

I completed my model of the gears within Fusion, and exported them for printing.

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CTEC607 #12

With the code wheel now in place, I can test the transfer of rotation using a belt.

With a rubber band wound around the base of the record pin, and around the encoder pin I tested the accuracy of the rotation transfer. It was not very good. Without a way to properly hold the belt I found it slipped often, and rode down the pin.

If I am to use a belt effectively, it should have more tension, and be positioned long term. The gears within the pre-existing system arent sized correctly to use for the code wheel. At Krishna’s suggestion I looked into 3D modelling my own gears. He suggested I look into a free CAD program called Fusion 360.

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CTEC607 #11

I began to dry fit my components and mark out where to machine holes on the base plate.

I began by prototyping with an aluminium scrap from the mechatronics lab. The hardware from the DJ mixer worked well, however the available tooling wasn’t suitable for working steel.

I started by drilling a hole in the base plate for the bushing which held the code wheel. With the code wheel in place, I could mark a positioning channel for the encoder sensor at the edge of the baseplate. I used the drill press again to mill a channel for the sensor, using jewellery files to clean up the channel. Using a two part epoxy, I glued the bushing in place.

I am happy with the progress made today, and it looks like the internal system will be discrete and seamless.

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CTEC607 #10

After finding out how the encoder worked, I planned how I would place it so that it wouldn’t bind on and of the other internals of the turntable.

I will use the bushing and hardware from the DJ mixer to hold the encoder square to the sensor. This will remove play and save time in fabrication.

I plan on using a band to take rotation from the record dish center pin.

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CTEC607 #9

I researched how I could use hardware and Arduino to track the speed and direction of the record dish. I found a sensor called a rotary encoder, which counts incrementally as it rotates. They are often used in manufacturing to accurately control stepper motors/servos. There were various encoders, however an optical encoder seemed to be the best option.

I remember seeing a DJ mixer in the mechatronics lab which used spinning discs to mix. Fortunately, the optical sensor and code wheel were still intact, so I removed them with as little damage as possible.

The encoder module has two sensors (A and B). The band on the code wheel is actually many small black lines, which the sensor counts. If the sensor counts A before B, the code wheel is spinning clockwise, if the sensor counts B before A, the code wheel is spinning anti-clockwise. The sensor operates on 5V power - perfect for an Arduino.

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CTEC607 #8

The first step in creating our turntable involves tracking speed and velocity of the spinning record dish.

Above is the inside of the record player. The central pin that the record dish sits on is mounted on a steel plate. There are mechanical gears which are used for the stop and queue functions.

I plan on removing these gears, or using them somehow to track the speed and direction of the dish discretely from within the player. I imagine Arduino will be helpful with this.

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CTEC607 #7

After discussions with Clint and the group, we have decided to try to define where we want to be on open studio night and how to achieve this.

Together we decided that we should create an installation which combines our skills and interests, and the experimentation/research we currently have.

The majority of my current work involves processing based programs, however I have an interest in fabrication. As a result I pushed to be responsible for the back end of the installation, the interface system and the program which runs the installation. Gabrielle and Erin from the beginning were interested in the visuals in the front end of the installation.

We ultimately decided on an installation which plays a sporadic visual loop at variable speed. The speed and direction the loop plays at can be manipulated by a hacked record player. The record on the record player can be heard by the audience at the same speed and direction as the looping visuals.

I will be using the weeks approaching studio to hack a record player to track the speed and direction of spin, translate this to a program which plays the looping visuals. The visuals will be created by Gabrielle and Erin.

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CTEC607 #6

An artist I found particularly interesting, with respect to affective and immersive works is Ryoji Ikeda. After looking at various works, I decided to try to emulate some of the imagery he uses. In particular, I like works such as ‘point of no return’, which use aggressive flashing and strobe like effects. This, and the stark b/w contrast reminded me of TV static.

I used processing to emulate a tv static effect, which generated particles based on a preset value. To further modify this code, I used the amplitude of music input to adjust the volume of particles generated.

A screen recording of this can be found within the linked google drive folder labelled ‘rain static’.

I feel that I achieved a stylistically similar effect to ‘point of no return’ with the strobe. I can however see that processing struggles with the generation of many entities/heavy lifting, and that optimisation could improve the effect. Instead of processing, I could approach another application which allows for more efficient use of computer resources. Something like max msp or after effects to create pre-rendered footage are alternatives.

I found an image of how this could be displayed in installation, as a multiplexed monitor setup.

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CTEC607 #5

I have been particularly interested in the differences between analogue and digital audio/video. I want to see how I can bridge the gap between the two. This came partially from my experimentation within creative audio, by using record players and vinyl in unorthodox conditions. I found myself interested in the tactility and feeling of spinning, scratching and manipulating sound with a physical interface. I felt more attentive to the sounds inscribed on the vinyl when I was actively manipulating the speed/direction it played at. I can see how this, similar to the way I used the webcam within processing, could be an effect method for receiving input from an audience, and encourage deeper engagement within our final installation.

I want to see how this could be linked to the visuals we have been creating.

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CTEC607 #4

How can we use experimental audio/visual imagery to affect and immerse an audience?

I see experimental as something that:

- Challenges or manipulates an existing paradigm.

- Explores new methods or ideas.

In the context of our question, imagery is:

- Visual or auditory stimuli

To affect is to incite an immediate reaction.

To immerse, we hope to capture an audiences attention, and to maintain engagement.

Screens (2010) offers valuable information on the relationship between audience and screen based installation. A physical copy is available from AUT library, and an E-book available online.

I spent some time using Adobe After Effects to create a slit scan of existing video footage. I really like the surrealism this effect imparts, however I would like to take more influence from the space odyssey and use more abstract patterns and colours.

References:

Mondloch, K. (2010). Screens : viewing media installation art. University of Minnesota Press.

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CTEC607 #3

We have a research question - How can we use experimental audio/visual imagery to affect and immerse an audience?

After framing our question, we begun research/experimentation.

I spent some time using processing to create a webcam fed slit scanner.

I like the surrealism of the slit scan, however I would like to expand on the code by feeding it with pre recorded film.

I also spent some time looking into P2D and P3D rendering within processing.

We stumbled upon a website holding many examples using processing - Form and Code. There is a physical book available containing these examples.

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CTEC607 #2

My initial group has dissolved.

I am now in a group with Erin Abernethy and Gabrielle Hislop.

We will be developing an installation with a focus on affective audience reaction and intensity.

Initial ideas started with projection of an animated sequence developed using Maya software. This is something we would like to explore, however after a talk with Clint we have broadened horizons.

I personally would love to look at physical/digital interactions.

Possible inspiration

- The slit scan effect used in Space Odyssey (https://www.youtube.com/watch?v=NaK4z3Fjpkk) was both intense and what I would describe as ‘stomachy’.

- The album art and music of ‘Tool’ is particularly interesting to me as affective work.

10,000 Days (https://www.youtube.com/watch?v=GSVqnUs2zCU&t=2300s)

Aenima (https://www.youtube.com/watch?v=yCXrgASzf50&t=3531s)

- The artist responsible for some of these works - Alex Grey (https://m.alexgrey.com/art/) was interesting in relation to depiction of DMT experiences.

Moving forward as a group, I believe it is important to establish a daily schedule of how we will distribute our time to certain tasks.

I would love to spend an hour of unrestricted worm-holing on research.

Following this, an hour of productive experimentation using discovered applications or methods during research.

We should probably spend some time sharing things we found interesting during this process with the other group members.

We will be developing a more defined schedule today.

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CTEC607 #1

I have been looking at the development of an audio/visual installation with a focus on audience manipulation and generation of atmosphere/mood.

I have a particular interest in furthering my audio/video editing skills and inquiry of audience response and reaction to triggers.

To do this, I would like to intentionally mislead an audience by feeding them exaggerated truths from external sensors/data streams. The audience is then to respond to their experience which will impact the display permanently.

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