4 ms·

If I'm not mistaken this improves a critical bottleneck on GPS precision, solutions to which will open up amazing applications. Driving lane boundaries just bei

If I'm not mistaken this improves a critical bottleneck on GPS precision, solutions to which will open up amazing applications. Driving lane boundaries just being one example.

AlotOfReading 1y ago
It could improve accuracy and does help a significant error factor, but the biggest error sources in GNSS aren't clock errors. Even a perfect clock could still have several meters of error.
rcxdude 1y ago
The main errors in GPS are usually due to variation in the propagation of the signals through the atmosphere, and uncertainty in the exact position of the satellites. (Solutions for these exist, but are generally too expensive and/or impractical for a lot of applications. But e.g. realtime GPS on the order of cm is something you can get now, if you pay for a subscription to the right service or operate your own reference base station)
gerdesj 1y ago
I'm not sure using a web of satellite borne clocks to do location to say three inches or 10cm accuracy is a great idea, especially when the "device" is moving at say 70mph. Not only that, you will need some amazingly exact maps that agree with the satellites' idea of "location". Lane awareness accuracy needs some serious looking at. Lane markings are designed for the human eye for obvious reasons. Those white lines and "cats eyes" are quite literally (lol) visual cues to keep you on track. If we want machines to drive for us then we will need other ways to do lane compliance, rather than just assist. My Chinese designed MG4 EV has lane assist. It certainly has four optical cameras but beyond that, I don't know - I think it has a fore and aft proximity sensor of some sort. I do know it makes some dreadful errors of judgment with regards lanes. It's normally fine on a motorway or dual carriageway but gets confused on even a major A road (eg A30) when there are striations in the road surface or its wet or the sun is at the right angle to make skid marks look like lines. If roads had something like a steel wire armoured cable buried underneath each lane and boundary line and there was a suitably cheap detector and sensors that could look far enough ahead and model the road then that might be a reasonably cheap option to augment optical systems. Now, more sensors cost money, sorry, cost profits. They also add complexity and so on. Sadly I think we will continue to see daft things like ... I gather that Teslas will only sport optical sensors and no LIDAR. Autonomous cars are possible but they do need to be given a decent amount of, and variety of, ... sensors. GPS will get you very well located on a map but you need local sensors to sort out localisation issues.

If I'm not mistaken this improves a critical bottleneck on GPS precision, solutions to which will open up amazing applications. Driving lane boundaries just being one example.

AlotOfReading 1y ago

It could improve accuracy and does help a significant error factor, but the biggest error sources in GNSS aren't clock errors. Even a perfect clock could still have several meters of error.

rcxdude 1y ago

The main errors in GPS are usually due to variation in the propagation of the signals through the atmosphere, and uncertainty in the exact position of the satellites. (Solutions for these exist, but are generally too expensive and/or impractical for a lot of applications. But e.g. realtime GPS on the order of cm is something you can get now, if you pay for a subscription to the right service or operate your own reference base station)

gerdesj 1y ago

I'm not sure using a web of satellite borne clocks to do location to say three inches or 10cm accuracy is a great idea, especially when the "device" is moving at say 70mph. Not only that, you will need some amazingly exact maps that agree with the satellites' idea of "location". Lane awareness accuracy needs some serious looking at. Lane markings are designed for the human eye for obvious reasons. Those white lines and "cats eyes" are quite literally (lol) visual cues to keep you on track. If we want machines to drive for us then we will need other ways to do lane compliance, rather than just assist. My Chinese designed MG4 EV has lane assist. It certainly has four optical cameras but beyond that, I don't know - I think it has a fore and aft proximity sensor of some sort. I do know it makes some dreadful errors of judgment with regards lanes. It's normally fine on a motorway or dual carriageway but gets confused on even a major A road (eg A30) when there are striations in the road surface or its wet or the sun is at the right angle to make skid marks look like lines. If roads had something like a steel wire armoured cable buried underneath each lane and boundary line and there was a suitably cheap detector and sensors that could look far enough ahead and model the road then that might be a reasonably cheap option to augment optical systems. Now, more sensors cost money, sorry, cost profits. They also add complexity and so on. Sadly I think we will continue to see daft things like ... I gather that Teslas will only sport optical sensors and no LIDAR. Autonomous cars are possible but they do need to be given a decent amount of, and variety of, ... sensors. GPS will get you very well located on a map but you need local sensors to sort out localisation issues.