explain the physics

Gyroscope combined with a fan/rotor?

Simple enough. It is a gyro stabilised fan and it will fly horizontally in roughly the direction that you lean it towards. Quite ingenious.

Not unlike a model autogyro.

You can get one for about 30 bucks and take it apart. Then you can explain it to yourself and others. Called Wonder Sphere.

It's a cute special effect. A longer treatment than the youtube, is a character in Vesper

which is analyzed on the 'extras' of the DVD release

In message snipped-for-privacy@googlegroups.com, RichD <r snipped-for-privacy@yahoo.com writes

The Galaspheres featured in Space Patrol operate on this principle . They use Yobba Rays to achieve escape velocity.

Brian

It looks like a single propeller. How does it perform tricks in

The propeller itself is also a gyro, which complicates things.

No it is all one thing - except that there is a circular bar inside the frame that spins up with the fan and is probably where most of the gyro effect comes from. The whole spinning part provides gyro stabilisation and the angle you set it off from determines the trajectory.

Not really it is one distributed mass gyro but the gyro contribution is dominated by the parts that are furthest from the axis of rotation whilst the lift is mainly generated by the fan. There is also a little bit of lift from the spinning ball effect so beloved of cricketers.

And worth adding that it relies on the inertia of the frame to give it a few seconds of lift before the frame starts rotating and effectively slowing down the fan.

It is still a cute physics toy - I want one!

.

Joe