Our Reflections

(Do we need individual reflections? If needed, put links to posts here)

How our project started

Our initial vision was to improve access to clean drinking water for those living in rural areas of developing countries. In such countries, there is a sizeable proportion of individuals that mainly commute by cycling. This is partly due to the distant location of water wells from their homes. Unfortunately, research has shown that well water from several villages is highly turbid, which decreases the appeal and potability of the water for drinking. So, we hoped to utilise the rotational motion of the bike to power a water filtration system powered by reverse osmosis (RO). After the individual obtains water from the well, the water will be filtered as he or she travels via bike, providing clean drinking water the moment he or she returns home.

How our project ended up

Over time, we kept the main idea of obtaining clean water from renewable energy but did away with the bicycle as the systems involved were too complex for the scope of our project. We decided on using a hand crank system instead to generate the power required for reverse osmosis. While our finalised idea cannot be directly applied to solve the problem that our initial idea hoped to achieve, this project serves to act as a proof of concept and show that human motion can power electrical devices (that are not limited to water filtration systems) used in our daily lives.

We divided the project into two main systems to achieve our goals:

1. Electrical Power System
2. Pump Filtration System

Electrical Power System

Thinking back, there were numerous problems faced with this system. However, we found solutions to each of the problems we faced eventually (after much trial and error).

1. Improvements to Cranking System motivated by improving the voltage generator can produce

One way is to increase the gear ratio. When things fail, then need to troubleshoot and redo.

Pump Filtration System

1. Rough Assembly works generally fine

2. RO Membrane able to remove food colouring

3. Dirty Water Tank size to be adjusted to modify power requirement

4. Arrangement still tentative – in progress

2. Improvements to Power Requirement of Pump

– general awareness of pressure of water affecting water input into the pump

– questions about not straining pump strainer and general preprocessing of dirty water -> Pre-Filter Assembly

Our learning points

1. Importance of BMS to regulate charging batteries in series and for safety

2. Importance of calculations in installing and assembling electrical circuit components to meet requirements for intended outcome

3. Importance of design specificity – be more careful in measurements (whether to give leeway of a mm for casing design)

4. Importance of orientation, relative positions of water, tank size and other factors that will affect power requirement, simple but significant