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Derive the expected proportion of bird flights at equidistant height bands between the lowest and highest points of the rotor. In other words, returns the flight height distribution at collision risk (\(d(y)\)).

Usage

get_fhd_rotor(hub_height, fhd, rotor_radius, tidal_offset, yinc = 0.05)

Arguments

hub_height

A numeric value, the height of the rotor hub (\(H\)), given by the sum of rotor radius and minimum blade clearance above the highest astronomical tide (HAT), in metres.

fhd

A numeric vector, the proportion of bird flights per-1 metre height bands from sea surface, starting from 0-1 metre band.

rotor_radius

A numeric value, the radius of the rotor (\(R\)), in metres.

tidal_offset

A numeric value, the tidal offset, the difference between HAT and mean sea level, in metres.

yinc

A numeric value, the increment for height bands between the lowest and highest points of the rotor, expressed as a proportion of rotor radius (defaults is 0.05).

Value

A numeric vector, the flight height distribution at collision risk, i.e. between minimum and maximum rotor height.

Examples


 gen_fhd_dat <- Johnston_Flight_heights_SOSS %>%
       dplyr::filter(variable=="Gannet.est") %>%
       dplyr::select(height,prop)
 if(is.data.frame(gen_fhd_dat)) gen_fhd <- gen_fhd_dat$prop

 get_fhd_rotor(
   hub_height = 150,
   fhd = gen_fhd,
   rotor_radius = 120,
   tidal_offset = 2.5,
   yinc = 0.05)
#>  [1] 4.080875e-01 2.184714e-01 1.166795e-01 6.212004e-02 3.294138e-02
#>  [6] 1.738272e-02 9.120000e-03 4.746000e-03 2.454000e-03 1.252200e-03
#> [11] 6.348000e-04 3.174000e-04 1.560000e-04 7.566000e-05 3.600000e-05
#> [16] 1.680000e-05 7.674000e-06 3.426000e-06 1.488000e-06 6.270000e-07
#> [21] 2.568000e-07 1.015200e-07 3.870000e-08 1.422000e-08 5.004000e-09
#> [26] 1.680000e-09 5.406000e-10 1.650000e-10 4.776000e-11 1.305600e-11
#> [31] 3.348000e-12 8.058000e-13 1.812000e-13 3.804000e-14 7.374000e-15
#> [36] 1.321200e-15 2.184000e-16 3.300000e-17 4.554000e-18 5.706000e-19
#> [41] 6.468000e-20