The goal of the project is to engage Engineering students from HKU through a series of project-based experiential learning activities that lead to a final weeklong visit to Dagon University in Myanmar. A key objective of this project is to allow students from Hong Kong and Myanmar to understand and appreciate the role of technologies in developing a sustainable urban living environment in spite of their geographical and socio-economical differences.
It serves as a unique learning experience for HKU students as they have to develop, prepare and deliver the teaching materials, as well as to construct the project with students in Myanmar throughout this process. Learning from last year’s experience, we intend to focus this year’s project on the theme of urban farming and food production. The focus on farming and food production adds an important dimension to the project where HKU students, who are mainly brought up in well developed urban settings, and Dagon University students, who are living a developing country, can engage in intellectual exchanges through technologies that aim to address a common global problem on food production through urban farming.
Interdisciplinary teaching team
This project was started in June 2018 initiated by the Engineering faculty at the University of Hong Kong.
Teachers from various departments worked together to design an experiential learning programme for students to work on one of the major environmental sustainability issues of the 21st century – Sustainable urban farming.
Our project is aimed at making farmers in Myanmar better informed on the soil conditions for farming. We have identified 4 of the main parameters that can help us analyze soil condition which are humidity, air temperature, soil temperature and soil moisture. Our device is designed to measure numerically all 4 of the above parameters. It achieves this by using individual sensors for each component all of which is intricately placed on the Arduino board. The device is powered by a battery with a solar panel. A WI-FI connection would be setup using an antenna which supports a radius of 100m. Additionally, the Raspberry Pi would serve as a local server. Data from the device would then be sent to ThingSpeak a Cloud-based API which will enable us to store, process and visualize the data. Finally, depending on the facilities available on-site, we may consider connecting the device to a water pump or have a mechanical support to lift it above the ground.
Prototyping and testing stage
To ensure that our work on the device moves along a structured and planned manner allowing us to explore various options along with keeping with the deadlines, we have divided our project into 3 major milestones each pertaining to meet advanced environmental conditions. These are as follows:
1)First-stage milestone (Data Transmission under ideal environment)
In this scenario, we assume that we have stable internet condition throughout. This scenario serves as our preliminary testing and prototyping conditions. The sensors used in this scenario measures resistive soil moisture, soil temperature, air temperature and humidity. The Arduino device is placed in a well-defined box and hot glue, dehydration powder, plastic bag and Nano spread particle were used as water-proofing options for the box. The device is powered by a power-bank which charges and discharges simultaneously. In this scenario, we assume that the router will support us with a 100m radius internet network using which the data can be sent through. The data is sent to Thingspeak, an open-source API to store and retrieve data. The data is then sent to the AWS Lambda function which formats the data and sends it across to the webpage for visualization purpose.
2) Second-stage milestone (Adaptation for Wi-fi & Energy constrained Environment & improved security)
In this scenario, we assume that we have irregular internet connection which would affect our data transmission to the cloud. Ideally, in this case we wish to ensure that we could store the readings offline in our database so that no data is lost. The sensors used for this scenario are Current and Voltage sensor (MAX471), Capacitive soil moisture sensor (SEN0193), RSSI and Switch. The device structure team also considered more advanced considerations in this case. For human touch detection, a switch would be placed which would trigger the device to be switched on. To ensure that minimal amounts of sensors would be directly exposed to adverse conditions, necessary adjustments were made on the box. Our data design for the irregular internet connection scenario is such that the data from Arduino is sent to Raspberry Pi wherein MongoDB acts as the database. This ensures that no data is lost.
3)Third-stage milestone (Exploration for more sensors & Energy optimization)
After laying the foundation of the device, in this scenario our team wishes to try out the possibility of using various sensors and optimizing the use of energy. The sensors tried in this scenario are pH, soil salinity, soil conductivity, leaf moisture & temp, CO2 measurement and GPS. For energy optimization, the possibility of using 3.3V was tried instead of 5V. Additionally optimization of battery current I/O and sleep mode were explored.
This section includes the Deployment of the device:
1. The teaching workshops (By July 30)
2. The field trips
3. The deployment and data collection
4. Feedback from stakeholders