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I used to work in perception for autonomous aerial vehicles and horizontal wires were the hardest common object to avoid. Traditional stereo won't help you loc
by riotnrrd 10mo ago
I used to work in perception for autonomous aerial vehicles and horizontal wires were the hardest common object to avoid. Traditional stereo won't help you localize them -- wires are thin so even mere detection can be hard, and one portion of a wire looks much like another so feature matching fails resulting in bad or no depth estimates -- and LIDAR sacrifices resolution for weight and power consumption (which both have to be optimizied for drones). It's been years since I've worked in this field, and Amazon has many smart people thinking about it but I'm not surprised it's still a difficult problem.
- vpShane 10mo agoAh yeah I came up with the solution to that one. It's 'don't fly drones over our heads' approach. Also the 'upgrade the fragile infrastructure so a light breeze doesn't take out millions of people's power.'
- venturecruelty 10mo agoSorry, not profitable enough, not a "team player". Please enjoy these weekly 1:1s with your manager and HR.
- bri3d 10mo agoDefinitely tough. mmWave radar is useful for this use case; I know Amazon were testing it on earlier drones but I'm not sure if they still use it.
- londons_explore 10mo agoCables don't move often. Why not simply have a map of all of them? Google sell maps of things like this from street view data.
- riotnrrd 10mo agoAll cables? Everywhere in the entire country? Accurate to the centimeter level and updated on the hour? Edit: This was flippant, but the real issues are: any map you get will be incomplete and obsolete almost immediately and cables move and sway in the breeze.
- lazide 10mo agoIt doesn’t need to be at the cm level. Giving them a 10m berth should be fine.
- anamexis 10mo agoA 10m berth from wires would exclude a substantial proportion of houses in my city.
- lazide 10mo agoThen they shouldn’t be flying in your city. As is apparently becoming obvious.
- ejoso 10mo agoI can’t think of a major city I’ve been to on earth where 10M from a hung cable is realistic outside of some suburbs and rural areas.
- throwaway2037 10mo ago> I can’t think of a major city I’ve been to on earth Does Manhattan count? I am pretty sure south of 96th street has no above ground utilities.
- HenrikB 10mo agoOpenStreetMap supports annotating poles and theirs cables. It's common for power lines (local and long distance). There are also annotations for communication lines (https://wiki.openstreetmap.org/wiki/Tag:communication%3Dline https://wiki.openstreetmap.org/wiki/Tag:communication%3Dline). There are also public and proprietary "aviation obstacle" databases across the world.
- octoberfranklin 10mo agoAny one particular cable might not move often, but if a telco owns N bucket trucks it's a safe bet that about N cables move every workday. Telcos are notoriously secretive about the location of their fiber. They even got most state legislatures to exempt it from state-level FOIA laws.
- c22 10mo agoIf you have a map of all utility poles you could probably just avoid every straight line between any of them within some reasonable distance of eachother.
- drjasonharrison 10mo agoit's an approximation of dangerous areas, catenary curves are more accurate than straight lines but you don't know the length of the cable so you don't know the droop height.
- euroderf 10mo agoOpenPoleMap is achievable. Just don't expect local governments to subsidise the mapping of obstacles to drones of the likes of Amazon.
- octoberfranklin 10mo agoMost "utility pole maps" only show poles with power lines on them. A ton of telco cables are on telco-only poles (basically just a really straight tree trunk shoved in the ground, no cross-arms at all).
- deleted 10mo ago[deleted]
- cesarb 10mo ago> Traditional stereo won't help you localize them [...] and LIDAR sacrifices resolution for weight and power consumption I wonder if a more mechanical solution wouldn't help: Whiskers, like on a cat. A long enough set of thin lightweight whiskers could touch the wire before the propellers do, giving time for the drone to stop and change course. Essentially, giving the drone a sense of touch.
- cromka 10mo agoWould help avoid damage with other misrecognized or ignired objects, too.
- ianferrel 10mo agoThin lightweight whiskers are going to be challenging to manage on a propeller-driven vehicle. They'll get blown all over the place. Having them extend out past the propellers will likely get them tangled in the propellers.
- ssl-3 10mo agoSure, they'll move around in the prop wash. But that's fine, isn't it? If they're intended to detect fixed objects, then noticing that one or more of them have ceased to be blown around in that way may be a good way to detect unanticipated contact with a fixed object: When the signal becomes less noisy, then maybe something is in the way. And the whiskers don't have to be all floppy like a wet noodle. I myself am thinking that something rigid or semi-rigid might be good. Perhaps something akin to armature wire, or thin spring steel. Maybe even literal bamboo chopsticks. They can also be constrained so that they don't get sent into the props. My little brain thinks that the drone-end of the whiskers can be attached to potentiometers, with light return springs to bring them back towards center, like the mechanism used by an analog stick on a PS3 controller.
- thaumasiotes 10mo ago> And the whiskers don't have to be all floppy like a wet noodle. I myself am thinking that something rigid or semi-rigid might be good. I don't think you're right about this. The concept of the whiskers is to notice when you've collided with something. Real whiskers aren't rigid because colliding with something when you're rigid means snapping. (Ever stub your toe?) Think of the rigidity of the whiskers as being traded off against your maximum movement speed.
- parliament32 10mo ago> horizontal wires were the hardest common object to avoid... Traditional stereo won't help you localize them This makes a lot of sense. I wonder if it wouldn't be better for autonomous vision to use three cameras instead of two for better spatial reasoning.. maybe in a triangle pattern?
- riotnrrd 10mo agoWe experimented with a rig with more cameras on it (four, in a square) but the baseline of the cameras on the drones we were using could be measured in centimeters, so the vertical stereo pairs didn't provide much better results. Further, more cameras means more power, more weight, and much more expensive on-board processing (which also will require more power).
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- wat10000 10mo agoIt’s really hard for people too. The advice I got for landing in a field was to assume that every pole you saw had wires going to every other pole. Which is reasonable enough for that scenario, but not workable for continual low altitude flying in a built up area.
- PunchyHamster 10mo agoIt's very simple: don't fly there there are very little aerial lines few meters highers and ones that exist can be probably spotted from satellite images and planned around. Especially if delivery area is limited, they could just map them out of the routes.
- thinkcontext 10mo ago> Traditional stereo won't help you localize them Wouldn't making a quick circuit around the house before landing allow wires to be observed from multiple angles be enough?
- drjasonharrison 10mo agoYes but tradeoffs with delivery speed, and thin wires are still hard to detect with limits on vision processing.
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- rkagerer 10mo agoHelicopter pilots have trouble with them as well.