4 ms·

This kind of little speaker-microphone 'sonar' is the kind of project we would give to undergraduate students as an afternoon practical. It's simple stuff to ge

by mjb 14y ago

This kind of little speaker-microphone 'sonar' is the kind of project we would give to undergraduate students as an afternoon practical. It's simple stuff to get going. The real magic that would make this useful is the signal processing and tracking algorithms which turn the extremely inaccurate raw data into something that provides a good user experience. A few kHz (the gap between what the speakers can do and human hearing) isn't much bandwidth, so this system is going to be highly affected by the tradeoff between range accuracy and Doppler accuracy. If they are attempting to do bistatic (two transmitters) tricks to derive spatial position, then this information will be similarly inaccurate.

yummybear 14y ago
I would imagine that most of the real magic will lie in making it work, and work well, as an input method - the video makes it look painfully awkward to use. Even Kinect which works relatively precisely is extremely annoying for anything else than kicking balls around on a screen. Even without interruptions like your children walking in front of the TV, getting Kinect to register an interaction correctly is a process of carefully performing some strange gesture like a wizard executing a spell while on LSD, and then doing it 5 more times until Kinect deems it precise enough. Personally I don't imagine this becoming more precise in the near future than to be useful for perhaps turning pages on a reader or tablet.
electromagnetic 14y ago
This is completely out of my field, but would it be possible to dope a soundtrack with an audible signal to extend your bandwidth, without the actual music causing more interference than the extra bandwidth is worth? I'd assume that you should be able to predict the type of background noise created by the soundtrack reflecting off a person sitting in front of a computer at a predetermined distance. In 90% of cases we're going to be talking a person sitting in front of a desk. Again, this is way out of my ballpark.

by mjb 14y ago

yummybear 14y ago

I would imagine that most of the real magic will lie in making it work, and work well, as an input method - the video makes it look painfully awkward to use. Even Kinect which works relatively precisely is extremely annoying for anything else than kicking balls around on a screen. Even without interruptions like your children walking in front of the TV, getting Kinect to register an interaction correctly is a process of carefully performing some strange gesture like a wizard executing a spell while on LSD, and then doing it 5 more times until Kinect deems it precise enough. Personally I don't imagine this becoming more precise in the near future than to be useful for perhaps turning pages on a reader or tablet.

electromagnetic 14y ago

This is completely out of my field, but would it be possible to dope a soundtrack with an audible signal to extend your bandwidth, without the actual music causing more interference than the extra bandwidth is worth? I'd assume that you should be able to predict the type of background noise created by the soundtrack reflecting off a person sitting in front of a computer at a predetermined distance. In 90% of cases we're going to be talking a person sitting in front of a desk. Again, this is way out of my ballpark.