Humming Urban Park is designed to provide visitors with a healing experience during a walk in the park. Large number of people are stressed from their daily life working or studying. It is especially strong in urban areas, where everyone is busy and there is no proper place to rest. These stressed people are weak both in physical and mental health, so we would like to provide them a place to enjoy and reduce their stress. Through our research, we have found that good sounds, ambient lightings and the natural environment can help reduce stress, so we incorporated these elements into our designs.
When people steps on certain areas of the pathway in the park, it will read the pressure that is given and play different sounds. Different pressure level will play different sounds, so each people will create different distinctive sounds. Each sounds different people makes will be mixed to play one music that everyone can enjoy. Instruments are chosen carefully, so they can be mixed harmonically together and played smoothly. While lights are played ambient lights will be lighting up to attract people's view the natural environment surrounding them instead of them focusing on their smartphone.
The main central part of our design is built on Arduino. Our team used Arduino Uno to process input data from sensors and output data to play sounds and lights on NeoPixel LED strips.
Load cell sensor takes main sensor role of our design. Load cell sensor is a sensor to measure the weight and usually used in scales. We have used 4 of 50kg load cells per set of plate which allows it to measure up to 200kg of weight. 200kg of weight would be around 3-4 adults. These load cell sensors are not directly connected to Arduino but connected to HX711 load cell amplifier which converts 24-bit analog data to digital data. The weight data that is measured by load cell sensor will be sent to Arduino as input data digitally passing through the HX711 sensor.
Our team has used NeoPixel LED strip as an output method to present the status of the product. NeoPixel LED strip is formed with large number of LED pixels that can create various of colors.
The main body of our design are the plates that people step on. These pads are made from 2 layers of wood plates on top and bottom. Wood has been used as the main body material as wood is strong enough to hold weight of people, but easy to shape and decorate as we want. In between these wooden plates load cell sensors are placed. Even though wood is strong, it is not firm enough to keep resistance against the load cell that is made with metal. We have placed a piece of metal between the wood plates and load cell, so the load cell sensor does not dig into the wood and keep the sensor working properly. Also, to keep the level and space between top and bottom wood plates and to provide users a smooth stepping experience soft sponges have been placed between.
Main coding has been done in Arduino where it processes the input readings from load cell sensors with HX711 library and controls the output on NeoPixel LED and MIDI. When the pressure value from load cell is read it will classify the pressure to range that has been set. According to the classified range it will output the MIDI key value that will be passed on key to MIDI to play sound and output various colors accordingly.
To play sounds in Ableton and control the sounds with Arduino, Arduino had to become MIDI (Muscial Instrument Digital Interface) to send MIDI keys to Ableton software. When certain actions are done in Arduino, it will send the MIDI key information accordingly. ‘Loop Midi Serial’ program has been used to create a MIDI port on PC and ‘hairless MIDI serial’ is used to create a bridge between Arduino and MIDI port created by ‘Loop MIDI’ so the computer can process the MIDI signal outputted by Arduino.
Ableton has been used to mix different instruments and sounds to play together. Each sound played by various instrument can be mapped by MIDI signal sent from Arduino.
At the beginning of the exhibition day, our work attracted visitors and many of them were willing to interact with our design. However, we could not fully provide the experience we designed due to number of issues that arose.
There were number of hardware issues with our design and some of them were known issues that we tried to prevent and some unexpected.
Our main issue we continued to experiecne was that the connections between each pad and Arduino were not strong and continued to disconnect. As our design consists of many numbers of different parts and each of them connected with thin cables soldered, they would easily break off while moving them around. We tried to supplement this issue by soldering strongly and taping the connection area. However, on the exhibition day our team had to move our product multiple times and even we took caution some of the connections became unstable.
Other issue we did not expect was the Arduino power issue. During the test phase we only had issues with 3 sensors, so we reduced to 2 and had no issues. During the actual exhibition our Arduino continued to shut down and get disconnected. This issue was caused by LED consuming too much power from Arduino.
Due to these issues that arose, in a short period of time our team modified our product and codes to resolve this problem but was not able to provide the full experience that we intended to the visitors.
Visitors who visited our venue included students, university staffs, and some guests with children. Students and staffs are our main target group, so we tried to get as much as feedbacks from them.
After interacting with our product, many numbers of visitors were curious how this design could be implemented in real life situation in a bigger scale. Due to lack of resources our product only portrays very small area of the big design we originally had, and this was difficult for the visitors to imagine our idea properly. We tried to explain our big picture well and some visitors understood the design well and some had difficulties.
Even though our product did not provide the visitors the full experience, after explaining our idea, many visitors liked our design. Some of the visitors loved our selection of music, and they commented that the chosen instruments sounded calm, and they think they would get some healing experience from the sounds. The light presentation was also attractive to the visitors. Some users mentioned that they will use our design if they encounter with our design in future.
Due to difficulty of explaining the big picture of our design with such small partial area, we think it would be great to provide the visitors with some visual aid in future. Creating a 3D environment for visitors to interact with would be a good visual support for the visitors to understand our design better.
As correcting the issues, making wire connections between each part stronger and safer would be important for future. Using multiple arduino or more powerful arduino would be also tried for future.