<?xml version="1.0" encoding="utf-8" standalone="yes"?><rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>Partial Maps | Haozhe Lei</title><link>https://panshark.github.io/tags/partial-maps/</link><atom:link href="https://panshark.github.io/tags/partial-maps/index.xml" rel="self" type="application/rss+xml"/><description>Partial Maps</description><generator>HugoBlox Kit (https://hugoblox.com)</generator><language>en-us</language><lastBuildDate>Thu, 17 Sep 2026 00:00:00 +0000</lastBuildDate><image><url>https://panshark.github.io/media/icon_hu_702a800cd775dbac.png</url><title>Partial Maps</title><link>https://panshark.github.io/tags/partial-maps/</link></image><item><title>MAPLE-RF: Localization with Partial Maps</title><link>https://panshark.github.io/projects/maple-rf-partial-map-localization/</link><pubDate>Thu, 17 Sep 2026 00:00:00 +0000</pubDate><guid>https://panshark.github.io/projects/maple-rf-partial-map-localization/</guid><description>&lt;p&gt;I lead &lt;strong&gt;MAPLE-RF&lt;/strong&gt;, an efficient probabilistic RF source-localization method for environments that are still being mapped. The core problem is common in robotic search: a receiver knows its own pose, but most of the surrounding floor plan may remain unobserved, including obstacles that could block or reflect the signal.&lt;/p&gt;
&lt;div class="project-video-shell"&gt;
&lt;video controls playsinline preload="metadata" poster="featured.png" aria-describedby="maple-video-description"&gt;
&lt;source src="maple-rf-demo.mp4" type="video/mp4"&gt;
Your browser does not support embedded MP4 video.
&lt;/video&gt;
&lt;/div&gt;
&lt;p id="maple-video-description"&gt;&lt;em&gt;The simulation follows a receiver along a recorded route while the observed map grows and the transmitter posterior is updated.&lt;/em&gt;&lt;/p&gt;
&lt;div class="project-figure-grid" aria-label="MAPLE-RF method and exploration figures"&gt;
&lt;figure class="project-figure-card"&gt;
&lt;img src="maple-method.png" alt="MAPLE-RF pipeline aligning multipath measurements with partial-map and receiver-centered spatial channels to infer a transmitter posterior." loading="lazy" decoding="async"&gt;
&lt;figcaption&gt;&lt;strong&gt;Inference before the map is complete.&lt;/strong&gt; RF paths are aligned with map knownness, occupancy, visibility, receiver pose, bearing, and range before one network pass scores candidate source locations.&lt;/figcaption&gt;
&lt;/figure&gt;
&lt;figure class="project-figure-card"&gt;
&lt;img src="maple-exploration.png" alt="MAPLE-RF current and accumulated source-location posteriors as a receiver follows an exploration route and reveals more of the map." loading="lazy" decoding="async"&gt;
&lt;figcaption&gt;&lt;strong&gt;Belief accumulation during exploration.&lt;/strong&gt; Current measurements and accumulated posteriors sharpen the source belief as the receiver moves and the observed map expands.&lt;/figcaption&gt;
&lt;/figure&gt;
&lt;/div&gt;
&lt;h2 id="method"&gt;Method&lt;/h2&gt;
&lt;p&gt;MAPLE-RF aligns estimated path angles and SNRs with spatial channels for map knownness, occupancy, line-of-sight visibility, receiver pose, bearing, and range. A residual U-Net then scores every candidate transmitter location in one pass. Unlike a full-grid digital-twin query, inference does not ray-trace every candidate whenever the map or receiver pose changes.&lt;/p&gt;
&lt;h2 id="findings"&gt;Findings&lt;/h2&gt;
&lt;ul&gt;
&lt;li&gt;Training across mixed levels of map coverage is essential for localization with unexplored space.&lt;/li&gt;
&lt;li&gt;MAPLE-RF retained about 94% of its complete-map 1-m recall when 75-85% of the map was unobserved.&lt;/li&gt;
&lt;li&gt;Fresh-query inference was about 218 times faster than full-grid general-purpose ray tracing in the evaluated configuration.&lt;/li&gt;
&lt;li&gt;Bayesian accumulation along exploration routes placed more posterior probability near the source than the compared baselines.&lt;/li&gt;
&lt;/ul&gt;
&lt;p&gt;The current study is simulation-based. Its role in the broader research program is to make posterior RF localization practical when a robot must localize and map concurrently, before a complete digital twin is available.&lt;/p&gt;
&lt;p&gt;&lt;strong&gt;Paper:&lt;/strong&gt;
— first and corresponding author; IEEE ICRA 2027, under review.&lt;/p&gt;</description></item></channel></rss>