A drone for last-centimeter delivery 

Interesting idea :) However it means that the recipient would have to interact with the drone in order to remove the parcel from inside of the cage. How can you make sure that user secured the cage appropriately and the drone is ready for a return journey? Looks like any deformation of the geometry created in the process of removing the parcel could cause serious problems. Thumb up for the project ;)

Walking is indispensable for good thinking and for your health.

What is the weight of the cage?

Grab that wrong and you're still going to get fingers into the propellers. Why not just put smaller cages around those?

Come on, if it can't be fully automated it's useless for deliveries. You're not going to have a person set this thing up each time instead of doing the walk themselves. And come the hell on, you want people to grab it themselves and unload it themselves??? This is totally impractical in the real world.

These people are on drugs - there is no way that's a practical AND profitable way of delivering a whopping 0.5 KG package. A bike messenger has more range, more weight allowance, and is just as fast - without the numerous pieces of technology that the drone system requires for it to work. This must have been the Switzerland Uni's - PIE IN THE SKY design class to come up with something so utterly useless.