← Anuja Saini

Project

LiDAR → Utility Network → Metadata, End-to-End

2025-06 to present

Free public LiDAR in, per-span power-line records out.

01The question

Can free public LiDAR replace paid utility survey flights?

Paid survey flights return 20 to 190 points per m², priced per line mile. USGS 3DEP is free and covers most of the US, but at 2 to 8 points per m².

Raw LiDAR return intensity over a utility corridorRaw LiDAR return intensity over a utility corridor
Return intensity per point.

The same corridor, segmented into poles, wires, ground and vegetationThe same corridor, segmented into poles, wires, ground and vegetation
Poles, wires, ground, vegetation.

02The problem

Thin a scan ten times and ground and trees keep their shape, but wires become scattered points and poles a smudge. The classes that matter fail first, and a model validated at survey density never sees it happen. Scores below are IoU, the overlap between prediction and truth, where 1 is perfect.

Same tile at 5 points per square metre, model trained at full density only: wires break up, poles vanishSame tile at 5 points per square metre, model trained at full density only: wires break up, poles vanish
5 pts/m²: wires break, poles vanish.
wire IoU 0.58pole IoU 0.42

Same tile at 5 points per square metre, model trained across densities: wires and poles intactSame tile at 5 points per square metre, model trained across densities: wires and poles intact
Same tile: wires and poles hold.
wire IoU 0.95pole IoU 0.65
at full density both scorewire IoU 0.96pole IoU 0.71

03What I built

  1. LiDAR
  2. segmentation
  3. topology
  4. wire separation
  5. metadata

Segmentation that survives sparsity

Every training tile is also thinned to 12, 8 and 5 points per m², so the model sees sparse data from the start. A large frozen encoder is gated into a small trainable backbone, adding its knowledge at no inference cost.

Topology in one forward pass

A four-channel height map feeds a dual-head network that predicts poles and wires together in one pass. The channels that depend on point labels are dropped at random in training, so the network still works when a scan is badly classified.

4-channel DSMResUNetFPNdual headchannel dropoutclDice lossglobal span assembly

One span → individual conductors

A learned separator and a geometric one fail in opposite situations, so a gate picks the better one per span. A catenary curve is then fitted to each conductor.

A span of seven transmission wires: raw above, separated into one colour per wire belowA span of seven transmission wires: raw above, separated into one colour per wire below
Raw, then per wire.

Metadata, one record per asset

With every conductor a fitted curve, the record writes itself: wire endpoints, pole heights and vegetation clearance. Clearance is the number that tells a utility where to trim before fire season.

wire endpoints and sagpole height and locationground clearancevegetation clearance

04Results

Segmentation

wire IoUpole IoU
USGS 3DEP, real scans at 3.5 pts/m²0.10 → 0.840.30 → 0.84
DALES0.86 → 0.960.47 → 0.72
ECLAIR, never seen in training0.88 → 0.980.16 → 0.74
Toronto-3D, never seen in training0.56 → 0.610.49 → 0.61
Pre-trained Point Transformer V3 (Pointcept), used as is → ours. Open datasets, one protocol, no retraining.

Network

  • ≥ 0.91pole detection, 0.4 to 193 pts/m², clean to badly classified
  • 99.8%precision assigning points to individual conductors

Poles become nodes and spans become edges, assembled across tiles so a span that crosses a tile boundary is still one edge.

Top row: the four DSM input channels for one tile. Bottom row: pole probability, wire probability, the predicted graph with eight poles, and the ground truth with eight polesTop row: the four DSM input channels for one tile. Bottom row: pole probability, wire probability, the predicted graph with eight poles, and the ground truth with eight poles
One tile: input channels, pole and wire heatmaps, predicted graph, ground truth. Eight poles in, eight out.

Metadata

  • 12–18 cmerror on conductor endpoint height and sag

Every conductor is a fitted curve through real returns, so each measurement is a simple query on the curve. Vegetation clearance is the number that decides where a wildfire can start.

One span with its measured endpoint heights, sag and cross-arm widthOne span with its measured endpoint heights, sag and cross-arm width
One span, measured.

05In production

  1. normalise
  2. segment
  3. clip spans
  4. topology
  5. polygonise
  6. metadata

Live in production. Six scale-to-zero endpoints, each on the instance type it needs, so shipping a new model is a configuration change.

06Impact

  • 500K+line miles · US, Canada, Europe · public, customer-flown and mobile LiDAR
  • 50K+line miles in a single job
  • Per-span vegetation clearance shipped as a product: where to trim before fire season.
  • 64 percent of one utility’s GIS spans recovered from public LiDAR alone.
  • Next: where no LiDAR was ever flown, teach a depth model the canopy heights this pipeline already produces, so imagery alone can fill the gaps.

07Research