Cascade of Wishes

by The Wizards of UQ

Modern Recreation of Traditional Well-Wishing Practice with Interaction and Technology

The "Cascade of Wishes" proposal is a modernised take on the traditional Hong Kong ritual of placing wishes on a well-wishing tree that incorporates elements of both the past and the present. Lighting up the tree, blooming the flowers, technology, and shared dreams all come together in perfect harmony in this installation, making it an unforgettable and significant experience that touches the minds and hearts of those experiencing it. It helps to preserve this beloved cultural tradition while also creating a sense of connection and belonging. We want to create engaging and transformative experiences that link people to the limitless possibilities of the digital world by seamlessly integrating traditional cultural practices with contemporary technical solutions. Our hope is that the Well-Wishing Tree idea will help keep cultural traditions alive and well while also making them more widely available and welcoming, so bringing people together regardless of where they live and encouraging them to feel more connected to one another. Cultural preservation, community participation, and artistic expression are all embraced in our vision, which embraces technology as a facilitator of important human interactions.


Blending modern technology with age-old cultural practices, our idea transforms the Hong Kong Wishing Tree ritual into an interactive and participatory event. Participants will enter a magical realm where the merging of digital and physical experiences can fulfil all your wishes. We want people to be empowered to pursue their dreams by giving them a chance to personalise their cards with colourful balls and meaningful wishes. Participants engage in the ancient ritual of offering wishes by physically preparing and flinging their placards onto the tree, symbolising dedication and perseverance in the process of dream-chasing. As they strive for success, the tree lights up, and a flower blooms, accompanied by celebratory audio feedback. With all the placards that carry wishes of every dreamer being hung on this magical tree, the Cascade of Wishes will be brought alive collaboratively. The project delivers an unforgettable and significant experience that goes across cultural boundaries and promotes a feeling of connection and belonging by seamlessly integrating physical movements, technology, and common ambitions.


Technical Description

The development of the Cascade of Wishes installation underwent several iterations and enhancements to achieve its final form. Initially conceived as a digital-based interaction triggering various animations through categorical gestures and placard tossing, it evolved into a fully physical installation to better align with the concept of "physical computing" interaction. This decision led to the creation of a physical tree structure with branches, leaves and trunk, incorporating technical components for control and operations. The final installation comprises five main components: the physical tree, placards, flowers, lights and technical elements.

  • Tree

    To construct the tree, inspiration was drawn from Pinterest and sketches were made to plan its assembly using cardboard, which was chosen for its combination of stiffness and lightness. A template of tree branches was created in Adobe Illustrator and segmented into printable A4-sized frames for easy assembly. Multiple replicas of the branches were then traced, cut and assembled with an intersection component made with intersected cardboard to form the first prototype of the tree. Leaves were also added to enhance realism. After prototyping, the decision was made to scale up the tree for better user interaction. The branches were thickened were small bits in-between the main branches being removed, so that more space was available for users to toss and hang their placards. Additional branches were also added for visibility from all angles, and the trunk with base from previous year's project was utilised for its height and stability. Securing the branches to the trunk involved creating rectangular holes on four sides of the trunk, which were used for inserting foam board and wood strips to serve as support. The branches were then attached using hot glue and further secured with wires to withstand the increasing weight of hung placards. To prevent imbalance and potential tipping, extra branches were added to the backside of the tree. These enhancements ensured the stability and safety of the installation, allowing users to engage fully in the traditional well-wishing practice without concern for structural integrity.


  • Placard

    The placard assembly process initially drew inspiration from the traditional practice, which involved tying red wish papers to tangerines. However, due to the weight and ripening issues of real tangerines, a ping pong ball equipped with an LED and a paper clay stem tied to red wish paper was settled upon. However, it was found upon testing that the ping pong ball was too lightweight for tossing and could not accommodate the LED. As a solution, it was replaced with a 5 cm diameter capsule which could be twist-opened in the middle. The clay stem was eliminated as it could not be used for securely tying the paper, so it was directly tied to the holes of the capsule instead. To adjust to using a load cell instead of an ultrasonic sensor for detecting successful placard hanging, clay was added inside the capsule to provide weight for the load cell to detect. Transparent coloured glass paper was placed inside the capsule to conceal the clay and LED battery while also providing a clear display of the user's chosen colour. Materials for the string used to tie the wish paper to the capsule were carefully considered, with viscose rayon string selected for its appropriate size, thickness, less prone to fraying and ease of use.


  • Flower

    Prior to developing the attractive blooming flower, we created a paper prototype to assess its functionality and evaluate participants' response. We were happy with the outcome. Due to the positive feedback, we decided to enhance our prototype by creating an improved version using 3D printing technology. Given our limited knowledge of 3D design, we extensively searched the Internet until we stumbled upon a helpful YouTube video containing the necessary files. However, there were certain challenges we encountered during our journey. We encountered difficulties during the printing process, specifically with the stem and support of the flower, despite our repeated attempts. After numerous attempts and adjustments to the settings, including reversing the stem, the desired outcome was ultimately achieved. The printing process took a total of four hours, and the support was handled separately and functioned smoothly. We had some difficulty finding the right wire initially, but eventually managed to locate it. Despite initial setbacks and the need for reprinting, we persevered and successfully assembled the blossoming flower. This achievement reflects our strong teamwork and unwavering commitment.


  • Technical Components

    Most of the technical elements are connected to and controlled by three Arduino boards. The first Arduino board is responsible for taking inputs from load cells using the Hx711 Library and determining if a user successfully hangs a ball on the tree. It is connected to the second Arduino board using UART(Universal Asynchronous Receiver/Transmitter) through the Tx and Rx pins. When a user successfully hangs a ball on the tree, the first Arduino board will send a message to the second Arduino board to trigger a series of events simultaneously, including changing the colour of the LED strip, rotating the servo, and playing a special sound effect. The LED strip and servo will change back to their original states after one second, whereas the sound effect will last for about 8 seconds.


    There are five force-sensitive resistors connected to the second Arduino board to help determine what colour the LED strip should change to. Each force-sensitive resistor corresponds to a wish type and a colour. There will be five balls on each force-sensitive resistor by default. If a ball is removed from a force-sensitive resistor, the force-sensitive resistor will detect it. The second Arduino board will then figure out which ball is picked up and what wish type is chosen. When the user hangs the ball on the tree, it will then send a message to the third Arduino board to change the colour based on the chosen wish type. Similarly, the servo is also connected to the second Arduino board. The Arduino board uses the Servo Library to rotate it for 180 degrees when a successful throw is detected. The servo will then pull the rope connected to the flower and open the flower.


    Since powering the LED strip can affect the accuracy of the values read from the force-sensitive resistors, the LED strip is powered by a third Arduino board. The third Arduino board is connected to the second Arduino board using I2C (Inter-Integrated Circuit) with the Wire Library. When a successful throw is detected, the second Arduino Board will send a message to the third Arduino board to tell it to change the LED strip to display a specific colour based on the chosen wish type. The Arduino board controls the colour of the LED strip using the Adafruit NeoPixel Library.


    Based on the feedback provided by users during the prototype demo, sound effects have been incorporated into the output media type to present a clearer and more engaging indication of successful throws. The implementation of sound effects as feedback is based on Unity reading Arduino's serial output. When a successful throw is detected, resulting in an increase in the weight of the tree, the second Arduino board will print and output a string "cheers" in the serial monitor. Unity's code then detects and reads this message from the Arduino serial. Upon receiving the "cheers" string, Unity triggers the mechanism for playing an audio clip. The display time for our sound effects and other visual outputs is set to 8 seconds. After eight seconds, the string "stop" is printed in Arduino's serial, which controls the cessation of the sound effect to ensure smooth feedback for subsequent throws. The addition of sound effects as feedback diversifies the output type and provides users with a clearer indication of successful throws. Furthermore, the celebratory nature of the sound effects enhances the user experience.


    Besides the components connected to the Arduino boards, the balls also have LEDs inside powered by button batteries. The inspiration for creating glowing balls comes from the "Glow in the Dark LED Ping Pong Ball" website. The materials used include button batteries and various colours of LED lights. Different colours of LED lights will correspond to different types of wishes. For example, a yellow ball will represent the type of wish card related to wealth. By encouraging more users to throw wishing placards combined with balls onto trees, the entire tree will become brighter. This will present users with a gradual change in the appearance of the physical object over time, thereby enhancing user experience and immersion. At the same time, it can also to some extent display the quantity of wishes of different types, allowing people to feel similar wishes and be inspired.