flightplanning-R

An R package for generating UAV flight plans, especially for Litchi.

Installation

This version of package should be installed using the devtools/remotes:

# install.packages("devtools")
devtools::install_github("gsapijaszko/flightplanning-R")

This fork

• adopts the package to R >= 4.2.0 (backward compatible) - DONE
• added grid = FALSE | TRUE parameter, which sets the flying direction over polygon - DONE
• added input for sf polygons -- roi can be read with sf::st_read() - DONE
• try to replace {rgdal}, {rgeos} and {sp} with {sf} - DONE; use litchi_sf() function
• incorporates changes from Hivemapper (see: caiohamamura#4)
• if you prefer to run in in QGIS, please check the QGIS processing script available on qgis r processing repo.

New function for testing

• litchi_sf()

Example usage

library(flightplanning)
f <- "mytest/lasek.gpkg"
roi <- sf::st_read(f)

output <- "mytest/fly.csv"

params <- flight.parameters(
  height = 120,
  focal.length35 = 24,
  flight.speed.kmh = 24,
  side.overlap = 0.8,
  front.overlap = 0.8
)

litchi_sf(roi,
  output,
  params,
  gimbal.pitch.angle = -90,
  flight.lines.angle = -1,
  max.waypoints.distance = 400,
  max.flight.time = 18,
  grid = FALSE
)
#> #####################
#> ## Flight settings ##
#> #####################
#> Min shutter speed: 1/128
#> Photo interval:    4 s
#> Flight speed:      23.364 km/h
#> Flight lines angle: 104.3223
#> Total flight time: 16.2097

Per default litchi_sf() takes first polygon from the input layer. If there is a need to run a mission over several polygons, you can union them like:

if(nrow(roi) > 1) {
  roi <- sf::st_union(roi)
}

litchi_sf(roi,
          output,
          params,
          gimbal.pitch.angle = -90,
          flight.lines.angle = -1,
          max.waypoints.distance = 400,
          max.flight.time = 18,
          grid = FALSE
)
#> Your flight was splitted in 2 splits,
#> because the total time would be 26.91 minutes.
#> They were saved as:
#> mytest/fly1.csv
#> mytest/fly2.csv
#> The entire flight plan was saved as:
#> mytest/fly_entire.csv
#> #####################
#> ## Flight settings ## 
#> #####################
#> Min shutter speed: 1/128
#> Photo interval:    4 s
#> Flight speed:      23.364 km/h
#> Flight lines angle: 104.2442
#> Total flight time: 26.9055

Using grid = TRUE parameter you can change the direction of the grid like:

litchi_sf(roi,
          output,
          params,
          gimbal.pitch.angle = -90,
          flight.lines.angle = -1,
          max.waypoints.distance = 400,
          max.flight.time = 18,
          grid = TRUE
)

Usage

There are two main functions available:

• flight.parameters(): this will calculate the flight parameters given desired settings for GSD/height, target overlap, flight speed and camera specifications.
• litchi_sf(): it depends on the flight.parameters() return object to generate the CSV flight plan ready to import into the Litchi Hub.

flight.parameters

• height: target flight height, default NA
• gsd: target ground resolution in centimeters, must provide either gsd or height
• focal.length35: numeric. Camera focal length 35mm equivalent, default 20
• image.width.px: numeric. Image width in pixels, default 4000
• image.height.px: numeric. Image height in pixels, default 3000
• side.overlap: desired width overlap between photos, default 0.8
• front.overlap: desired height overlap between photos, default 0.8
• flight.speed.kmh: flight speed in km/h, default 54.

litchi_sf

• roi: range of interest loaded as an OGR layer, must be in a metric units projection for working properly
• output: output path for the csv file
• flight.params: Flight Parameters. parameters calculated from flight.parameters()
• gimbal.pitch.angle: gimbal angle for taking photos, default -90 (overriden at flight time)
• flight.lines.angle: angle for the flight lines, default -1 (auto set based on larger direction)
• max.waypoints.distance: maximum distance between waypoints in meters, default 2000 (some issues have been reported with distances > 2 Km)
• max.flight.time: maximum flight time. If mission is greater than the estimated time, it will be splitted into smaller missions.
• starting.point: numeric (1, 2, 3 or 4). Change position from which to start the flight, default 1
• grid: boolean (FALSE | TRUE). Change the fly direction over polygon from parallel to perpendicular

Authors

• Caio Hamamura
• Danilo Roberti Alves de Almeida
• Daniel de Almeida Papa
• Hudson Franklin Pessoa Veras
• Evandro Orfanó Figueiredo

This package was developed by author and its contributors which helped providing the calculations and testing.

Example

# Install and load the package
install.packages("flightplanning")
library(flightplanning)

params = flight.parameters(height=100,
                          flight.speed.kmh=54,
                          side.overlap = 0.8,
                          front.overlap = 0.8)
                          
params

## Slot "flight.line.distance": 
## [1] 34.61329 
##  
## Slot "flight.speed.kmh": 
## [1] 46.72794 
## 
## Slot "front.overlap":
## [1] 0.8
## 
## Slot "gsd":
## [1] 4.326662
## 
## Slot "height":
## [1] 100
## 
## Slot "ground.height":
## [1] 129.7998
## 
## Slot "minimum.shutter.speed":
## [1] "1/289"
## 
## Slot "photo.interval":
## [1] 2

# Load example SpatialDataFrame polygon
exampleBoundary = readOGR(
                          system.file("extdata", 
                                      "exampleBoundary.shp", 
                                      package="flightplanning"), 
                          "exampleBoundary")

# Set the output
output = "output.csv"

# Create the csv plan 
litchi_sf(exampleBoundary,
            output,
            params,
            flight.lines.angle = -1,
            max.waypoints.distance = 2000,
            max.flight.time = 15)
            
# Your flight was splitted in 2 splits,
# because the total time would be 27.62 minutes.
# They were saved as:
# output1.csv
# output2.csv
# The entire flight plan was saved as:
# output_entire.csv
# #####################
# ## Flight settings ## 
# #####################
# Min shutter speed: 1/289
# Photo interval:    2 s
# Flight speed:      46.7279 km/h
# Flight lines angle: 39.0626
# Total flight time: 27.6239

References

FIGUEIREDO, E. O. et al. Planos de Voo Semiautônomos para Fotogrametria com Aeronaves Remotamente Pilotadas de Classe 3. Acre: EMBRAPA. 2018