while a real brake would be cool and all, what about just one of those cheap spring loaded magnetic solanoids with a 'tooth' on the end that engages into a disk with holes in it or something? id think with the right machineing config it could engage even at speed, and while it might not be the gentalist of things, its not like your head will be moving at extream speed, and this is an 'emergency' brake, not an 'every day every operation' brake.
they also have a decent amount of force if you only allow them to open a mm or two, you could use one as a friction brake too.. (though realise some are not rated for staying open at 100% duty cycle!) |