mirror of https://github.com/ArduPilot/ardupilot
357 lines
17 KiB
Lua
357 lines
17 KiB
Lua
-- Copter attempts to fly home using dead reckoning if the GPS quality deteriorates or an EKF failsafe triggers
|
|
--
|
|
-- CAUTION: This script only works for Copter 4.3 (and higher)
|
|
-- this script checks for low GPS quality and/or an EKF failsafe and if either occurs, flies in the last known direction towards home
|
|
--
|
|
-- DR_ENABLE : 1 = enabled, 0 = disabled
|
|
-- DR_ENABLE_DIST : distance from home (in meters) beyond which the dead reckoning will be enabled
|
|
-- DR_GPS_SACC_MAX : GPS speed accuracy maximum, above which deadreckoning home will begin (default is 0.8). Lower values trigger with good GPS quality, higher values will allow poorer GPS before triggering. Set to 0 to disable use of GPS speed accuracy.
|
|
-- DR_GPS_SAT_MIN : GPS satellite count threshold below which deadreckoning home will begin (default is 6). Higher values trigger with good GPS quality, Lower values trigger with worse GPS quality. Set to 0 to disable use of GPS satellite count.
|
|
-- DR_GPS_TRIGG_SEC : GPS checks must fail for this many seconds before dead reckoning will be triggered.
|
|
-- DR_FLY_ANGLE : lean angle (in degrees) during deadreckoning. Most vehicles reach maximum speed at 22deg
|
|
-- DR_FLY_ALT_MIN : min alt (above home in meters) during deadreckoning. zero to return at current alt
|
|
-- DR_FLY_TIMEOUT : timeout (in seconds). Vehicle will attempt to switch to NEXT_MODE after this many seconds of deadreckoning. If it cannot switch modes it will continue in Guided_NoGPS. Set to 0 to disable timeout
|
|
-- DR_NEXT_MODE : flight mode vehicle will change to when GPS / EKF recovers or DR_FLY_TIMEOUT expires. Default is 6=RTL, see FLTMODE1 parameter description for list of flight mode number. Set to -1 to return to mode used before deadreckoning was triggered
|
|
|
|
-- How to use:
|
|
-- 1. set SCR_ENABLE = 1 to enable scripting (and reboot the autopilot)
|
|
-- 2. set SCR_HEAP_SIZE to 80000 or higher to allocate enough memory for this script
|
|
-- 3. set DR_ENABLE = 1 to enable dead reckoning
|
|
-- 4. optionally set DR_GPS_SACC_MAX and/or DR_GPS_SAT_MIN parameters to adjust how bad the GPS quality must be before triggering
|
|
-- 5. confirm "DR: waiting for dist (Xm < 50m)" message is displayed on ground station (so you know script is working)
|
|
-- 6. arm and takeoff to a safe altitude
|
|
-- 7. fly at least DR_ENABLE_DIST meters from home and confirm "DR: activated!" is displayed on ground station
|
|
--
|
|
-- If this script senses low GPS quality or an EKF failsafe triggers:
|
|
-- - vehicle will change to Guided_NoGPS mode
|
|
-- - vehicle will lean in the last known direction of home (see DR_FLY_ANGLE)
|
|
-- - if GPS recovers or EKF failsafe is cleared the vehicle will switch to DR_NEXT_MODE (if -1 then it will switch back to the mode in use before the GPS/EKF failure)
|
|
-- - if the timeout is surpassed (see DR_FLY_TIMEOUT) the vehicle will try to switch to DR_NEXT_MODE. If it fails to change it will continue in Guided_NoGPS but keep trying to change mode
|
|
-- - the pilot can retake control by switching to an "unprotected" mode like AltHold, Loiter (see "protected_mode_array" below)
|
|
--
|
|
-- Testing in SITL:
|
|
-- a. set map setshowsimpos 1 (to allow seeing where vehicle really is in simulator even with GPS disabled)
|
|
-- b. set SIM_GPS_DISABLE = 1 to disable GPS (confirm dead reckoning begins)
|
|
-- c. set SIM_GPS_DISABLE = 0 to re-enable GPS
|
|
-- d. set SIM_GPS_NUMSAT = 3 to lower simulated satellite count to confirm script triggers
|
|
-- e. set DR_GPS_SACC_MAX = 0.01 to lower the threshold and trigger below the simulator value which is 0.04 (remember to set this back after testing!)
|
|
--
|
|
-- Test on a real vehicle:
|
|
-- A. set DR_FLY_TIMEOUT to a low value (e.g. 5 seconds)
|
|
-- B. fly the vehicle at least DR_DIST_MIN meters from home and confirm the "DR: activated!" message is displayed
|
|
-- C. set GPS_TYPE = 0 to disable GPS and confirm the vehicle begins deadreckoning after a few seconds
|
|
-- D. restore GPS_TYPE to its original value (normally 1) and confirm the vehicle switches to DR_NEXT_MODE
|
|
-- E. restore DR_FLY_TIMEOUT to a higher value for real-world use
|
|
-- Note: Instaed of setting GPS_TYPE, an auxiliary function switch can be setup to disable the GPS (e.g. RC9_OPTION = 65/"Disable GPS")
|
|
--
|
|
-- Testing that it does not require RC (in SITL):
|
|
-- a. set FS_OPTIONS's "Continue if in Guided on RC failsafe" bit
|
|
-- b. set FS_GCS_ENABLE = 1 (to enable GCS failsafe otherwise RC failsafe will trigger anyway)
|
|
-- c. optionally set SYSID_MYGCS = 77 (or almost any other unused system id) to trick the above check so that GCS failsafe can really be disabled
|
|
-- d. set SIM_RC_FAIL = 1 (to simulate RC failure, note vehicle keeps flying)
|
|
-- e. set SIM_RC_FAIL = 0 (to simulate RC recovery)
|
|
--
|
|
-- Test with wind (in SITL)
|
|
-- a. SIM_WIND_DIR <-- sets direction wind is coming from
|
|
-- b. SIM_WIND_SPD <-- sets wind speed in m/s
|
|
--
|
|
|
|
-- create and initialise parameters
|
|
local PARAM_TABLE_KEY = 86 -- parameter table key must be used by only one script on a particular flight controller
|
|
assert(param:add_table(PARAM_TABLE_KEY, "DR_", 9), 'could not add param table')
|
|
assert(param:add_param(PARAM_TABLE_KEY, 1, 'ENABLE', 1), 'could not add DR_ENABLE param') -- 1 = enabled, 0 = disabled
|
|
assert(param:add_param(PARAM_TABLE_KEY, 2, 'ENABLE_DIST', 50), 'could not add DR_ENABLE_DIST param') -- distance from home (in meters) beyond which the dead reckoning will be enabled
|
|
assert(param:add_param(PARAM_TABLE_KEY, 3, 'GPS_SACC_MAX', 0.8), 'could not add DR_GPS_SACC_MAX param') -- GPS speed accuracy max threshold
|
|
assert(param:add_param(PARAM_TABLE_KEY, 4, 'GPS_SAT_MIN', 6), 'could not add DR_GPS_SAT_MIN param') -- GPS satellite count min threshold
|
|
assert(param:add_param(PARAM_TABLE_KEY, 5, 'GPS_TRIGG_SEC', 3), 'could not add DR_GPS_TRIGG_SEC parameter') -- GPS checks must fail for this many seconds before dead reckoning will be triggered
|
|
|
|
assert(param:add_param(PARAM_TABLE_KEY, 6, 'FLY_ANGLE', 10), 'could not add DR_FLY_ANGLE param') -- lean angle (in degrees) during deadreckoning
|
|
assert(param:add_param(PARAM_TABLE_KEY, 7, 'FLY_ALT_MIN', 0), 'could not add DR_FLY_ALT_MIN param') -- min alt above home (in meters) during deadreckoning. zero to return at current alt
|
|
assert(param:add_param(PARAM_TABLE_KEY, 8, 'FLY_TIMEOUT', 30), 'could not add DR_FLY_TIMEOUT param')-- deadreckoning timeout (in seconds)
|
|
assert(param:add_param(PARAM_TABLE_KEY, 9, 'NEXT_MODE', 6), 'could not add DR_NEXT_MODE param') -- mode to switch to after GPS recovers or timeout elapses
|
|
|
|
-- bind parameters to variables
|
|
function bind_param(name)
|
|
local p = Parameter()
|
|
assert(p:init(name), string.format('could not find %s parameter', name))
|
|
return p
|
|
end
|
|
local enable = bind_param("DR_ENABLE") -- 1 = enabled, 0 = disabled
|
|
local enable_dist = bind_param("DR_ENABLE_DIST") -- distance from home (in meters) beyond which the dead reckoning will be enabled
|
|
local gps_speed_acc_max = bind_param("DR_GPS_SACC_MAX") -- GPS speed accuracy max threshold
|
|
local gps_sat_count_min = bind_param("DR_GPS_SAT_MIN") -- GPS satellite count min threshold
|
|
local gps_trigger_sec = bind_param("DR_GPS_TRIGG_SEC") -- GPS checks must fail for this many seconds before dead reckoning will be triggered
|
|
local fly_angle = bind_param("DR_FLY_ANGLE") -- lean angle (in degrees) during deadreckoning
|
|
local fly_alt_min = bind_param("DR_FLY_ALT_MIN") -- min alt above home (in meters) during deadreckoning
|
|
local fly_timeoout = bind_param("DR_FLY_TIMEOUT") -- deadreckoning timeout (in seconds)
|
|
local next_mode = bind_param("DR_NEXT_MODE") -- mode to switch to after GPS recovers or timeout elapses
|
|
local wpnav_speedup = bind_param("WPNAV_SPEED_UP") -- maximum climb rate from WPNAV_SPEED_UP
|
|
local wpnav_accel_z = bind_param("WPNAV_ACCEL_Z") -- maximum vertical acceleration from WPNAV_ACCEL_Z
|
|
|
|
-- modes deadreckoning may be activated from
|
|
-- comment out lines below to remove protection from these modes
|
|
local protected_mode_array = {
|
|
3, -- AUTO
|
|
4, -- GUIDED
|
|
--5, -- LOITER
|
|
6, -- RTL
|
|
7, -- CIRCLE
|
|
9, -- LAND
|
|
--11, -- DRIFT
|
|
--16, -- POSHOLD
|
|
17, -- BRAKE
|
|
21, -- SMART_RTL
|
|
27, -- AUTO_RTL
|
|
}
|
|
function is_protected_mode()
|
|
local curr_mode = vehicle:get_mode()
|
|
for i = 1, #protected_mode_array do
|
|
if curr_mode == protected_mode_array[i] then
|
|
return true
|
|
end
|
|
end
|
|
return false
|
|
end
|
|
|
|
local copter_guided_nogps_mode = 20 -- Guided_NoGPS is mode 20 on Copter
|
|
local copter_RTL_mode = 6 -- RTL is mode 6 on Copter
|
|
local recovery_delay_ms = 3000 -- switch to NEXT_MODE happens this many milliseconds after GPS and EKF failsafe recover
|
|
|
|
local gps_bad = false -- true if GPS is failing checks
|
|
local ekf_bad = false -- true if EKF failsafe has triggered
|
|
local gps_or_ekf_bad = true -- true if GPS and/or EKF is bad, true once both have recovered
|
|
|
|
local flight_stage = 0 -- 0. wait for good-gps and dist-from-home, 1=wait for bad gps or ekf, 2=level vehicle, 3=deadreckon home
|
|
local gps_bad_start_time_ms = 0 -- system time GPS quality went bad (0 if not bad)
|
|
local recovery_start_time_ms = 0-- system time GPS quality and EKF failsafe recovered (0 if not recovered)
|
|
local fly_start_time_ms = 0 -- system time fly using deadreckoning started
|
|
|
|
local home_dist = 0 -- distance to home in meters
|
|
local home_yaw = 0 -- direction to home in degrees
|
|
|
|
local target_yaw = 0 -- deg
|
|
local climb_rate = 0 -- m/s
|
|
|
|
local stage1_flight_mode = nil -- flight mode vehicle was in during stage1 (may be used during recovery)
|
|
local stage2_start_time_ms -- system time stage2 started (level vehicle)
|
|
local stage3_start_time_ms -- system time stage3 started (deadreckon home)
|
|
local last_print_ms = 0 -- pilot update timer
|
|
local interval_ms = 100 -- update at 10hz
|
|
|
|
function update()
|
|
|
|
-- exit immediately if not enabled
|
|
if (enable:get() < 1) then
|
|
return update, 1000
|
|
end
|
|
|
|
-- determine if progress update should be sent to user
|
|
local now_ms = millis()
|
|
local update_user = false
|
|
if (now_ms - last_print_ms > 5000) then
|
|
last_print_ms = now_ms
|
|
update_user = true
|
|
end
|
|
|
|
-- check GPS
|
|
local gps_primary = gps:primary_sensor()
|
|
local gps_speed_acc = gps:speed_accuracy(gps:primary_sensor())
|
|
if gps_speed_acc == nil then
|
|
gps_speed_acc = 99
|
|
end
|
|
local gps_speed_acc_bad = ((gps_speed_acc_max:get() > 0) and (gps_speed_acc > gps_speed_acc_max:get()))
|
|
local gps_num_sat = gps:num_sats(gps:primary_sensor())
|
|
local gps_num_sat_bad = (gps_sat_count_min:get() > 0) and ((gps_num_sat == nil) or (gps:num_sats(gps:primary_sensor()) < gps_sat_count_min:get()))
|
|
if gps_bad then
|
|
-- GPS is bad, check for recovery
|
|
if (not gps_speed_acc_bad and not gps_num_sat_bad) then
|
|
gps_bad = false
|
|
end
|
|
else
|
|
-- GPS is good, check for GPS going bad
|
|
if (gps_speed_acc_bad or gps_num_sat_bad) then
|
|
if (gps_bad_start_time_ms == 0) then
|
|
-- start gps bad timer
|
|
gps_bad_start_time_ms = now_ms
|
|
elseif (now_ms - gps_bad_start_time_ms > gps_trigger_sec:get()) then
|
|
gps_bad = true
|
|
end
|
|
end
|
|
end
|
|
|
|
-- check EKF failsafe
|
|
local fs_ekf = vehicle:has_ekf_failsafed()
|
|
if not (ekf_bad == fs_ekf) then
|
|
ekf_bad = fs_ekf
|
|
end
|
|
|
|
-- check for GPS and/or EKF going bad
|
|
if not gps_or_ekf_bad and (gps_bad or ekf_bad) then
|
|
gps_or_ekf_bad = true
|
|
gcs:send_text(0, "DR: GPS or EKF bad")
|
|
end
|
|
|
|
-- check for GPS and/or EKF recovery
|
|
if (gps_or_ekf_bad and (not gps_bad and not ekf_bad)) then
|
|
-- start recovery timer
|
|
if recovery_start_time_ms == 0 then
|
|
recovery_start_time_ms = now_ms
|
|
end
|
|
if (now_ms - recovery_start_time_ms > recovery_delay_ms) then
|
|
gps_or_ekf_bad = false
|
|
recovery_start_time_ms = 0
|
|
gcs:send_text(0, "DR: GPS and EKF recovered")
|
|
end
|
|
end
|
|
|
|
-- update distance and direction home while GPS and EKF are good
|
|
if (not gps_or_ekf_bad) then
|
|
local home = ahrs:get_home()
|
|
local curr_loc = ahrs:get_location()
|
|
if home and curr_loc then
|
|
home_dist = curr_loc:get_distance(home)
|
|
home_yaw = math.deg(curr_loc:get_bearing(home))
|
|
elseif (update_user) then
|
|
-- warn user of unexpected failure
|
|
gcs:send_text(0, "DR: could not get home or vehicle location")
|
|
end
|
|
end
|
|
|
|
-- reset flight_stage when disarmed
|
|
if not arming:is_armed() then
|
|
flight_stage = 0
|
|
fly_start_time_ms = 0
|
|
transition_start_time_ms = 0
|
|
return update, interval_ms
|
|
end
|
|
|
|
-- flight_stage 0: wait for good gps and dist-from-home
|
|
if (flight_stage == 0) then
|
|
|
|
-- wait for GPS and EKF to be good
|
|
if (gps_or_ekf_bad) then
|
|
return update, interval_ms
|
|
end
|
|
|
|
-- wait for distance from home to pass DR_ENABLE_DIST
|
|
if ((home_dist > 0) and (home_dist >= enable_dist:get())) then
|
|
gcs:send_text(5, "DR: enabled")
|
|
flight_stage = 1
|
|
elseif (update_user) then
|
|
gcs:send_text(5, "DR: waiting for dist:" .. tostring(math.floor(home_dist)) .. " need:" .. tostring(math.floor(enable_dist:get())))
|
|
end
|
|
return update, interval_ms
|
|
end
|
|
|
|
-- flight_stage 1: wait for bad gps or ekf
|
|
if (flight_stage == 1) then
|
|
if (gps_or_ekf_bad and is_protected_mode()) then
|
|
-- change to Guided_NoGPS and initialise stage2
|
|
if (vehicle:set_mode(copter_guided_nogps_mode)) then
|
|
flight_stage = 2
|
|
target_yaw = math.deg(ahrs:get_yaw())
|
|
stage2_start_time_ms = now_ms
|
|
else
|
|
-- warn user of unexpected failure
|
|
if (update_user) then
|
|
gcs:send_text(5, "DR: failed to change to Guided_NoGPS mode")
|
|
end
|
|
end
|
|
else
|
|
-- store flight mode (may be used during recovery)
|
|
stage1_flight_mode = vehicle:get_mode()
|
|
end
|
|
return update, interval_ms
|
|
end
|
|
|
|
-- flight_stage 2: level vehicle for 5 seconds
|
|
if (flight_stage == 2) then
|
|
-- allow pilot to retake control
|
|
if (vehicle:get_mode() ~= copter_guided_nogps_mode) then
|
|
gcs:send_text(5, "DR: pilot retook control")
|
|
flight_stage = 1
|
|
return update, interval_ms
|
|
end
|
|
|
|
-- level vehicle for 5 seconds
|
|
climb_rate = 0
|
|
vehicle:set_target_angle_and_climbrate(0, 0, target_yaw, climb_rate, false, 0)
|
|
if ((now_ms - stage2_start_time_ms) >= 5000) then
|
|
flight_stage = 3
|
|
stage3_start_time_ms = now_ms
|
|
gcs:send_text(5, "DR: flying home")
|
|
end
|
|
if (update_user) then
|
|
gcs:send_text(5, "DR: leveling vehicle")
|
|
end
|
|
return update, interval_ms
|
|
end
|
|
|
|
-- flight_stage 3: deadreckon towards home
|
|
if (flight_stage == 3) then
|
|
|
|
-- allow pilot to retake control
|
|
if (vehicle:get_mode() ~= copter_guided_nogps_mode) then
|
|
gcs:send_text(5, "DR: pilot retook control")
|
|
flight_stage = 1
|
|
return update, interval_ms
|
|
end
|
|
|
|
-- check for timeout
|
|
local time_elapsed_ms = now_ms - stage3_start_time_ms
|
|
local timeout = (fly_timeoout:get() > 0) and (time_elapsed_ms >= (fly_timeoout:get() * 1000))
|
|
|
|
-- calculate climb rate in m/s
|
|
if (fly_alt_min:get() > 0) then
|
|
local curr_alt_below_home = ahrs:get_relative_position_D_home()
|
|
if curr_alt_below_home then
|
|
local target_alt_above_vehicle = fly_alt_min:get() + curr_alt_below_home
|
|
if target_alt_above_vehicle > 0 then
|
|
-- climb at up to 1m/s towards target above vehicle. climb rate change is limited by WPNAV_ACCEL_Z
|
|
local climb_rate_chg_max = interval_ms * 0.001 * (wpnav_accel_z:get() * 0.01)
|
|
climb_rate = math.min(target_alt_above_vehicle * 0.1, wpnav_speedup:get() * 0.01, climb_rate + climb_rate_chg_max)
|
|
end
|
|
end
|
|
end
|
|
|
|
-- set angle target to roll 0, pitch to lean angle (note: negative is forward), yaw towards home
|
|
if (vehicle:set_target_angle_and_climbrate(0, -math.abs(fly_angle:get()), home_yaw, climb_rate, false, 0)) then
|
|
if (update_user) then
|
|
local time_left_str = ""
|
|
if (not timeout and (fly_timeoout:get() > 0)) then
|
|
time_left_str = " t:" .. tostring(math.max(0, ((fly_timeoout:get() * 1000) - time_elapsed_ms) / 1000))
|
|
end
|
|
gcs:send_text(5, "DR: fly home yaw:" .. tostring(math.floor(home_yaw)) .. " pit:" .. tostring(math.floor(fly_angle:get())) .. " cr:" .. tostring(math.floor(climb_rate*10)/10) .. time_left_str)
|
|
end
|
|
elseif (update_user) then
|
|
gcs:send_text(0, "DR: failed to set attitude target")
|
|
end
|
|
|
|
-- if GPS and EKF recover or timeout switch to next mode
|
|
if (not gps_or_ekf_bad) or timeout then
|
|
local recovery_mode = stage1_flight_mode
|
|
if (next_mode:get() >= 0) then
|
|
recovery_mode = next_mode:get()
|
|
end
|
|
if (recovery_mode == nil) then
|
|
recovery_mode = copter_RTL_mode
|
|
gcs:send_text(0, "DR: NEXT_MODE=-1 but fallingback to RTL")
|
|
end
|
|
-- change to DR_NEXT_MODE
|
|
if (vehicle:set_mode(recovery_mode)) then
|
|
flight_stage = 0
|
|
elseif (update_user) then
|
|
-- warn user of unexpected failure
|
|
gcs:send_text(0, "DR: failed to change to mode " .. tostring(recovery_mode))
|
|
end
|
|
end
|
|
return update, interval_ms
|
|
end
|
|
|
|
-- we should never get here but just in case
|
|
return update, interval_ms
|
|
end
|
|
|
|
return update()
|
|
|