The theme of our project for this year’s Science Fair was “Plants & Animals.” We decided to investigate the development or metamorphosis of a frog, but with a twist – we were going to design, build and test our very own robotic frogs using LEGO WeDo 2.0. Before we could build these, we needed to study the stages of a frog’s life from pond to lily pad, in order to understand the reasons why frogs’ bodies change over time. We then compared the life cycles of humans and plants to the metamorphoses of frogs during the “Explore” phase.
After watching videos of lots of types of frogs at various stages in their lives, we looked at what LEGO pieces we had that could be used to create robots that looked like the real thing. We then made some sketches of how we could build these during the “Design” phase:
Next: We built our designs during the “Create” phase in groups. The trickiest part of the create phase was when we had to redesign the froglet’s body to transform it into an adult frog but it was really interesting to see the variety of modifications chosen by the different groups in the classroom. We found that discussing the issues and reporting back as we went along was very useful in tweaking our design sketches:
A tadpole with unable to walk just yet. 
A young froglet spies some lunch! 
A froglet’s developing front legs.
Once we were happy with our designs and initial physical tests, it was time to revise what type of behaviour frogs might exhibit during their life cycle. Things such as eating, movement and reaction to predators were explored using videos and other online research. The LEGO WeDo app provided us with some great slow-motion videos for us to study the frog’s habitat. The challenge here was to programme our new robots to mimic the behaviour and basic movements of a young froglet and adult frog using motors, pulleys, gears and motion sensors.
After a lot of trial and error, lots of groups had noisy LEGO bees buzzing around hungry frogs as well as props representing various predators forcing our frightened little frogs to back away from danger! There was lots of excitement, discussion and comparisons made during this part of the “Share” phase of the project.
Click on the links below to see our finished Robotic frogs!
