{"id":782,"date":"2019-02-28T20:51:45","date_gmt":"2019-03-01T01:51:45","guid":{"rendered":"http:\/\/sunapi386.ca\/wordpress\/?p=782"},"modified":"2023-02-06T19:58:08","modified_gmt":"2023-02-07T00:58:08","slug":"transforming-lidar-point-clouds","status":"publish","type":"post","link":"https:\/\/sunapi386.ca\/wordpress\/transforming-lidar-point-clouds\/","title":{"rendered":"Transforming Lidar Point Clouds"},"content":{"rendered":"\n

I was playing with datasets and wanted to share with what beautiful visualizations but wrong map alignment looks like.<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

The different colors represent scans but merged improperly (not aligned).<\/p>\n\n\n\n

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Looks like a mess.<\/p>\n\n\n\n

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But overall the coloring is important with debugging what this data represents.<\/p>\n\n\n\n

<\/p>\n\n\n\n

Here’s what it looks like all merged together properly.<\/p>\n\n\n\n

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<\/p>\n\n\n\n

Especially the truck<\/p>\n\n\n\n

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<\/p>\n\n\n\n

Lidar map merging is a difficult task, and merging the data takes quite some time. So it is better to sample parts of a large data set and see if the algorithm is doing the right job.<\/p>\n\n\n\n

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At least the lidar above were all in the same 2D plane.<\/p>\n\n\n\n

<\/p>\n\n\n\n

Here’s what it looks like if they weren’t — a blob of mess.<\/p>\n\n\n\n

\"\"
double <\/strong>roll = rtkMessage.roll();
double <\/strong>pitch = rtkMessage.pitch();
double <\/strong>yaw = – rtkMessage.heading();<\/figcaption><\/figure>\n\n\n\n
\"\"<\/figure>\n\n\n\n
\"\"<\/figure>\n\n\n\n
\"\"<\/figure>\n\n\n\n
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double <\/strong>roll = deg2rad(rtkMessage.roll());
double <\/strong>pitch = deg2rad(rtkMessage.pitch());
double <\/strong>yaw = deg2rad(rtkMessage.heading());<\/figcaption><\/figure>\n\n\n\n
\"\"
double <\/strong>roll = deg2rad(rtkMessage.roll());
double <\/strong>pitch = deg2rad(rtkMessage.pitch());
double <\/strong>yaw = – deg2rad(rtkMessage.heading());<\/figcaption><\/figure>\n\n\n\n
\"\"<\/figure>\n\n\n\n

I tried a bunch of different methods and it turns out that I was using degrees in place of radians. <\/p>\n\n\n\n

Here’s what after 5 days of working on this problem I finally solved <\/p>\n\n\n\n

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<\/p>\n\n\n\n

Here’s what the Google Maps view looks like<\/p>\n\n\n\n

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<\/p>\n\n\n\n

And here’s what the lidar point cloud data only looks like<\/p>\n\n\n\n

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<\/p>\n\n\n\n

Different view<\/p>\n\n\n\n

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<\/p>\n\n\n\n

Construction crane can be seen here.<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n
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radians roll\/pitch<\/figcaption><\/figure>\n\n\n\n

Very interesting in the map stitch process!<\/p>\n","protected":false},"excerpt":{"rendered":"

I was playing with datasets and wanted to share with what beautiful visualizations but wrong map alignment looks like. The different colors represent scans but merged improperly (not aligned). Looks like a mess. But overall the coloring is important with debugging what this data represents. Here’s what it looks like all merged together properly. Especially … Continue reading Transforming Lidar Point Clouds<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[34],"tags":[],"class_list":["post-782","post","type-post","status-publish","format-standard","hentry","category-thoughts"],"_links":{"self":[{"href":"https:\/\/sunapi386.ca\/wordpress\/wp-json\/wp\/v2\/posts\/782","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sunapi386.ca\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/sunapi386.ca\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/sunapi386.ca\/wordpress\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/sunapi386.ca\/wordpress\/wp-json\/wp\/v2\/comments?post=782"}],"version-history":[{"count":5,"href":"https:\/\/sunapi386.ca\/wordpress\/wp-json\/wp\/v2\/posts\/782\/revisions"}],"predecessor-version":[{"id":1053,"href":"https:\/\/sunapi386.ca\/wordpress\/wp-json\/wp\/v2\/posts\/782\/revisions\/1053"}],"wp:attachment":[{"href":"https:\/\/sunapi386.ca\/wordpress\/wp-json\/wp\/v2\/media?parent=782"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/sunapi386.ca\/wordpress\/wp-json\/wp\/v2\/categories?post=782"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/sunapi386.ca\/wordpress\/wp-json\/wp\/v2\/tags?post=782"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}