June 11, Thursday

Firstly, we met over MS Teams and came up with an initial design plan. The workload was split and  propulsion legs were assigned to Chengxin, programming to Jordon, and frame, balloon and elevators to Rohan.

 

 

We designed 2 different types of legs with a squid’s movement in mind, segmented and non-segmented. Both designs were simulated under a buckling test in SolidWorks to find a good balance between strength and levity.

Then, the next important factor to consider was the thrust.

 

The segmented leg worked using the elasticity of the tape. A string was stuck on one end and strung to end through small holes made on both ends of all the segments. When pulled, the segments compressed together to form an s-shape. When released, the tape springs the segments back to the original configuration that is supposed to push the air. The simpler, non-segmented version employs rotational movement to push the air instead.

We conducted a rudimentary test using 3D printed, scaled down versions of both legs. The segmented leg was tested by pulling and pulling a string while the non-segmented leg was simply ‘flapped’ by hand. Apparently, we overestimated the springiness of tape and the non-segmented version was found to push a test mass further than the segmented version. This suggests that the non-segmented leg can produce a stronger propelling force. Thus, the segments were scrapped (no matter how cool-looking it was) and the right design was chosen for the squid’s propulsion legs.