Lidar mission planning
Swath, line spacing, and pulse density for a lidar flight, with the aggregate density over overlapping lines checked against the 3DEP quality levels.
Planning and education aid. Not for primary navigation. Full disclaimer
Experimental: not yet fully verified. How results are checked
Each line is 140 m wide; all lines together give 171.4 pulses per square meter.
- Line spacing
- Pulse density, one line
- Aggregate pulse density
- Point density
- USGS 3DEP quality level
Provenance
- Computed by
- drone.sensors.lidar-plan 1.0.1, core 0.1.0
- Model
- Swath = 2H tan(FOV/2); line spacing = swath (1 − side overlap); nominal pulse density = pulse rate ÷ (speed × swath) for one line, and ÷ (speed × line spacing) for the aggregate over overlapping lines; points = pulses × returns per pulse. Quality levels by aggregate nominal pulse density (USGS Lidar Base Specification 2025 rev. A, table 1)
- Accuracy
- Nominal and averaged across the swath: oscillating and non-repetitive scan patterns spread pulses unevenly, denser at the swath edges or center. Quality levels also set accuracy requirements that density alone does not meet; QL0 has QL1's density with tighter accuracy
- Notes
- 1 shown with the answer
- Cites
- U.S. Geological Survey, 3D Elevation Program, Lidar Base Specification
Something look off?
How we got thisFormula, worked example, sources, and proof
Model: Swath = 2H tan(FOV/2); line spacing = swath (1 − side overlap); nominal pulse density = pulse rate ÷ (speed × swath) for one line, and ÷ (speed × line spacing) for the aggregate over overlapping lines; points = pulses × returns per pulse. Quality levels by aggregate nominal pulse density (USGS Lidar Base Specification 2025 rev. A, table 1)
Show your work
Pulse density, one line
pulse rate ÷ (speed × swath)240,000 ÷ (10 × 140.04)= 171.4Swath width
2 × height × tan(FOV ÷ 2)2 × 100 × tan 35°= 140 m
The same steps an agent gets from the MCP server with explain: true.
Accuracy: Nominal and averaged across the swath: oscillating and non-repetitive scan patterns spread pulses unevenly, denser at the swath edges or center. Quality levels also set accuracy requirements that density alone does not meet; QL0 has QL1's density with tighter accuracy
Worked example: 240,000 pulses a second, 70° field of view, 100 m at 10 m/s. Source: add-practitioner-essentials lidar scenario: swath about 140.0 m and 171 pulses per m², beyond QL1. It is golden test vector v001, and every build checks the tool still gives its answer within its tolerance.
You enter
- Field of view
- 70 deg
- Flight height
- 100 m
- Pulse rate
- 240 kHz
- Groundspeed
- 10 m/s
You get
- Swath width
- 140 m
- Line spacing
- 140 m
- Pulse density, one line
- 171.4 pls/m²
- Aggregate pulse density
- 171.4 pls/m²
- Point density
- 171.4 pls/m²
- USGS 3DEP quality level
- QL1 (at least 8 pulses per m²)
Review: Not yet independently reviewed by a Part 107 remote pilot.
Last verified: 2026-09-22, when a maintainer last confirmed this tool's sources at the issuer. See the sources ledger.
Status: version 1.0.1, core 0.1.0. See this tool in the verification report.
Changes
- 2026-09-23, fixed: Plain-number results in a fixed unit now show that unit: the battery current reads 9.7 A where it read 9.7, and decibels, gigabytes, pulses per square meter, grams per kilogram, nautical miles per gallon, hours, nanoteslas, and minutes now carry their units too. The numbers themselves do not change. Each tool's patch version went up. Changelog
Checked against: 6 golden test vectors (download the test vectors, each with its source and tolerance). See how results are checked and every source.
Sources
- Lidar Base Specification, U.S. Geological Survey, 3D Elevation Program, 2025 rev. A (June 2025). Table 1: aggregate nominal pulse density, QL0 and QL1 ≥ 8.0, QL2 ≥ 2.0, QL3 ≥ 0.5 pulses per m².
Terms
- USGS: U.S. Geological Survey
- The US government science agency that runs the 3D Elevation Program and sets the quality levels for lidar data. Source: Lidar Base Specification
Experimental means this tool has not yet met the stable bar: at least 20 golden vectors, differential tests, and an independent worked example.
USGS — U.S. Geological Survey
The US government science agency that runs the 3D Elevation Program and sets the quality levels for lidar data.
Source: Lidar Base Specification