Fig. 08 · Agricultural · ArduCopter V4.7.2

Agricultural spray hexacopter

Fly it

Parts: …
Battery: unplugged
Fault: none

Loading the figure…

Pick the battery, motors and props. Every number below is recalculated from this craft's own model.

Battery

Motors

Props

Calculated for this build

All-up weight: 33,265 g
Thrust : weight: 2.0 : 1
Hover throttle: 72%
Max current: 458 A
Hover time: 12.7 min
Hard-flying time: 10.1 min

Checks

Parts match: 2.0:1 with 10 L aboard, enough margin to fight a gust while full. The calculator's hover throttle is pessimistic for these big slow props: Hobbywing measured 57 % at this load, and ArduCopter learns its own hover value (MOT_THST_HOVER). As the tank empties the drone gets 10 kg lighter and the hover throttle drops.

WarningIt hovers at 72% throttle: too little headroom to climb out or correct a gust.

Cost

Category	Parts	Cost
Electrical	9	$4,050
Mechanical	5	$1,180
Total (approx.)	14	$5,230

Every connection on the craft. Choose one to select both ends on the figure, or open the hand-inked wiring sheet.

power
motor phases
data / signal

power:AS150U anti-spark · 12S 44.4 V
The pack's AS150U anti-spark plug into the power board's lead. Its pre-charge resistor fills the ESC capacitors before the main pins touch, so 50 V doesn't arc across the plug and pit the contacts.
power:PDU pads · a 12 AWG pair down each arm
One 12 AWG red and black pair per arm, soldered to the power board's pads: about 13 A each in a hover, 80 A at the peak.
motor phases:3-phase × 6, inside each X8 pod
The three phase wires stay inside each X8 pod. A motor that spins the wrong way is fixed by swapping two of them, or by fitting the other-hand unit: the autopilot can't reverse a PWM ESC.
power:POWER1 · power brick · V/I sense
The X8 ESCs have no BEC, so a power brick takes the 12S bus down to a clean 5 V for the Cube and reports the pack's voltage and current on POWER1 (BATT_MONITOR 4).
power:12S bus to the pump driver
The pump driver takes its power straight from the 12S bus, through its own fuse.
data / signal:MAIN 1-6 · PWM 1050-1950 µs
MAIN 1 to 6 carry one PWM signal per motor (SERVO1 to 6 set to Motor1 to 6). MOT_PWM_MIN 1050 and MOT_PWM_MAX 1950 match the X8's range.
data / signal:AUX 1 · SprayerPump PWM
AUX 1 (SERVO9) is SprayerPump: the pulse width tells the driver how fast to run the pump.
data / signal:TELEM1 · MAVLink2 + RTCM · RCIN · SBUS
The telemetry radio on TELEM1 (SERIAL1, MAVLink2) carries the ground station's commands and the RTK corrections; the RC receiver's SBUS goes into RCIN.
data / signal:GPS1 + GPS2 · two F9P, moving baseline
GPS1, the front antenna and moving-baseline base, on the GPS1 port (SERIAL3); GPS2, the rover, on GPS2 (SERIAL4). The base sends its corrections to the rover, which works out the heading from them.
data / signal:TELEM2 · US-D1 serial, 115200
The radar on TELEM2 (SERIAL2 protocol 9, Rangefinder, 115200 baud) reports the height above the crop many times a second.

A working emulation of the ArduPilot Copter command line for this craft: real setting names, real limits and real error messages.

Connect tcp:127.0.0.1:5760 source_system=255

Up and down recall earlier commands.

Configuration snippets

Frame, motor outputs and power after the build

In ArduCopter 4.7.2 you set parameters, and MAVProxy stores each param set at once. Hexa X frame, the six motors on MAIN 1 to 6 by motor number. The X8's integrated ESC takes plain PWM between 1050 and 1950 µs, so MOT_PWM_TYPE stays Normal. The harmonic notch follows the throttle and sits at the blade-pass frequency: two blades at about 2400 rpm hum at 80 Hz. MOT_HOVER_LEARN 2 lets it learn its own hover throttle, which falls as the tank empties.

# ArduCopter 4.7.2 on a Cube Orange+: hexa X, six Hobbywing X8 units on MAIN 1-6, power brick on POWER1
param set FRAME_CLASS 2         # Hexa
param set FRAME_TYPE 1          # X: M1 right, M2 left, M3 front left, M4 rear right, M5 front right, M6 rear left
param set SERVO1_FUNCTION 33    # MAIN 1: Motor1
param set SERVO2_FUNCTION 34    # MAIN 2: Motor2
param set SERVO3_FUNCTION 35    # MAIN 3: Motor3
param set SERVO4_FUNCTION 36    # MAIN 4: Motor4
param set SERVO5_FUNCTION 37    # MAIN 5: Motor5
param set SERVO6_FUNCTION 38    # MAIN 6: Motor6
param set MOT_PWM_TYPE 0        # Normal PWM: the X8 takes 1100-1940 us, no DShot, no throttle calibration
param set MOT_PWM_MIN 1050      # Hobbywing's numbers for open-source autopilots
param set MOT_PWM_MAX 1950
param set MOT_SPIN_ARM 0.08     # armed idle: 30-inch props turn slowly and hit hard
param set MOT_HOVER_LEARN 2     # learn the hover throttle and save it in MOT_THST_HOVER
param set INS_HNTCH_ENABLE 1    # harmonic notch; refresh the parameters to see the rest
param set INS_HNTCH_MODE 1      # follow the throttle: PWM ESCs report no rpm
param set INS_HNTCH_FREQ 80     # Hz: about 2400 rpm x 2 blades at hover
param set BATT_MONITOR 4        # analog voltage and current from the power brick
param set BATT_CAPACITY 22000   # mAh
param set AHRS_ORIENTATION 0    # Cube arrow to the nose; 4 = Yaw180 if it points back
# FRAME_CLASS, the SERVOn_FUNCTIONs, INS_HNTCH_ENABLE and AHRS_ORIENTATION take effect after a reboot

Radio, radar and RTK after the build

The 900 MHz radio on TELEM1 carries MAVLink and the RTK corrections, and the radar talks to TELEM2. GPS1_TYPE 17 and GPS2_TYPE 18 make the two F9Ps a moving-baseline pair: the rover measures where it sits relative to the base, and that line is the heading. The antenna positions are in metres from the centre of gravity, with y to the right. With EK3_SRC1_YAW 2 the compass is left out, away from steel sheds and 450 A of power leads.

# The 900 MHz radio on TELEM1, the radar on TELEM2, the two F9P receivers on GPS1 and GPS2
param set SERIAL1_PROTOCOL 2    # MAVLink2: telemetry out, RTK corrections in
param set SERIAL1_BAUD 57       # 57600
param set SERIAL2_PROTOCOL 9    # Rangefinder
param set SERIAL2_BAUD 115      # 115200 for the US-D1
param set RNGFND1_TYPE 11       # USD1_Serial: the Ainstein US-D1 radar
param set RNGFND1_ORIENT 25     # looking down
param set RNGFND1_MIN 0.5       # m: the radar reads nothing closer (was RNGFND1_MIN_CM)
param set RNGFND1_MAX 45        # m
param set SERIAL3_PROTOCOL 5    # GPS1
param set SERIAL4_PROTOCOL 5    # GPS2
param set GPS1_TYPE 17          # u-blox moving-baseline base: the front antenna
param set GPS2_TYPE 18          # u-blox moving-baseline rover: the rear antenna
param set GPS_AUTO_CONFIG 1     # the Cube configures both F9Ps
param set GPS_AUTO_SWITCH 1     # use the better one; never 2 (blend) with a moving baseline
param set GPS1_POS_X 0.17       # m forward of the centre of gravity
param set GPS1_POS_Y -0.15      # m: ArduPilot's y points right, so masts on the left are negative
param set GPS2_POS_X -0.17
param set GPS2_POS_Y -0.15
param set EK3_SRC1_YAW 2        # heading from the two antennas, not a compass
param set COMPASS_USE 0         # steel sheds and a 450 A bus: leave the compass out
param set GPS_INJECT_TO 127     # RTK corrections to both receivers

The sprayer after the build

ArduPilot's sprayer runs the pump in proportion to the ground speed: SPRAY_PUMP_RATE 10 means 10 % per m/s, so 40 % at 4 m/s and 70 % at 7 m/s, and the dose per square metre stays the same. Below SPRAY_SPEED_MIN (1 m/s, still written in cm/s) it stops, so it never puddles in a hover. The switch on channel 7 permits spraying; flipped high while disarmed, it runs the pump test.

# The sprayer: enable it, refresh the parameters (the others stay hidden until it is on), then set it up
param set SPRAY_ENABLE 1
param set SERVO9_FUNCTION 22    # AUX 1: SprayerPump
param set SPRAY_PUMP_RATE 10    # % of full pump per m/s of ground speed: 40 % at 4 m/s
param set SPRAY_PUMP_MIN 0      # %: nothing when it stops
param set SPRAY_SPEED_MIN 100   # cm/s: no spray below 1 m/s (still centimetres in 4.7)
param set RC7_OPTION 15         # channel 7 switch: Sprayer Enable; high while disarmed = pump test
param set SERVO9_MIN 1000       # the pump driver's PWM range, from its manual
param set SERVO9_MAX 2000

Failsafes, fence and pre-arm checks after the build

Radio lost, or the ground station silent for 5 s: RTL. The low-battery level is 3.5 V per cell or 30 % left, then RTL; at the critical 3.4 V per cell it lands where it is. The fence keeps it below 30 m and within 300 m of home. 4.7 names the arming checks the other way round: ARMING_SKIPCHK lists the checks to skip, and 0 skips none.

# Radio lost, ground station lost, battery low and critical, a fence round the farm, every pre-arm check
param set FS_THR_ENABLE 1       # RC lost: RTL
param set FS_GCS_ENABLE 1       # no ground-station heartbeat for 5 s: RTL
param set BATT_LOW_VOLT 42      # 3.5 V per cell x 12 under load
param set BATT_LOW_MAH 6600     # or 30 % of the 22000 mAh left
param set BATT_FS_LOW_ACT 2     # low: RTL (FS_BATT_ENABLE no longer exists)
param set BATT_CRT_VOLT 40.8    # 3.4 V per cell
param set BATT_FS_CRT_ACT 1     # critical: land where it is
param set BATT_ARM_VOLT 48      # 4.0 V per cell: take off only on a fresh pack
param set FENCE_ENABLE 1
param set FENCE_TYPE 7          # max altitude + circle + polygon (the field edge)
param set FENCE_ALT_MAX 30      # m
param set FENCE_RADIUS 300      # m round home
param set ARMING_SKIPCHK 0      # skip no pre-arm check (4.7; was ARMING_CHECK 1)

Stabilize for Stabilize

The Cube levels the drone when the sticks are centred, but the throttle is the motors' power: nothing holds the height or the position. On a 33 kg drone with water sloshing in it, this is the mode for when the GPS or the radar has failed. ATC_ANGLE_MAX 25 limits the lean in every mode.

# Stabilize: self-levelling, the throttle stick is the motors. The last resort if the GPS or the radar goes
param set ATC_ANGLE_MAX 25      # max lean in every mode, degrees: 33 kg of water and drone swings hard
mode STABILIZE

AltHold for AltHold

The throttle stick asks for a climb or a descent, up to PILOT_SPD_UP 2.5 m/s, and centred it holds the height. With SURFTRAK_MODE 1 and the radar, that is the height above the crop rather than above the take-off point, so it rises and falls with the ground. Nothing holds the position: the wind pushes it.

# AltHold: the throttle stick asks for a climb rate; over crop the radar holds the height above it
param set PILOT_SPD_UP 2.5      # m/s at full stick (was PILOT_SPEED_UP 250)
param set SURFTRAK_MODE 1       # surface tracking: follow the ground the radar sees
mode ALT_HOLD

Loiter for Loiter

Holds height, position and heading with the sticks centred, to a few centimetres with RTK. Full stick flies at LOIT_SPEED_MS 8 m/s, and LOIT_ACC_MAX_M 3 keeps the starts and stops soft, so the water in the tank doesn't slosh the drone about.

# Loiter: RTK holds the position to a few centimetres, GPS yaw holds the heading
param set LOIT_SPEED_MS 8       # m/s at full stick (was LOIT_SPEED 800)
param set LOIT_ACC_MAX_M 3      # m/s/s: gentle with a full tank sloshing (was LOIT_ACC_MAX 300)
mode LOITER

Return to launch for RTL

Climbs to RTL_ALT_M 12 m, above the 10 m trees and the 9 m power line, flies home at 6 m/s and lands. The sprayer is not part of the mode: ArduPilot's sprayer library keeps the pump permitted across a mode change, so a mission ends every row with DO_SPRAYER 0, and a pilot turns the sprayer switch off before taking over. Otherwise it sprays the yard on the way home.

# Return to launch: climb to 12 m over the trees and the power line, fly home, land
# The pump does NOT stop on a mode change: DO_SPRAYER 0 ends every row, or flip the sprayer switch off
param set RTL_ALT_M 12          # m (was RTL_ALT 1200)
param set RTL_SPEED_MS 6        # m/s home (was RTL_SPEED 600)
param set RTL_ALT_FINAL_M 0     # 0 = land at home
param set LAND_SPD_MS 0.5       # m/s for the last metres
mode RTL

AUTO: the spray mission for AUTO spray

The mission is planned as a survey grid: rows one swath (4 m) apart, joined at the ends. Each row starts with DO_SPRAYER 1 and ends with DO_SPRAYER 0, so the pump runs only over the crop. WP_RFND_USE 1 and waypoints in the Terrain frame keep it 2.5 m above the crop by the radar. When it comes back from a refill, DO_SET_RESUME_REPEAT_DIST makes it rejoin the row a little before where it stopped, so no strip is missed. AUTO can't arm: arm in Loiter, then switch.

# The spray mission from a survey grid: six 36 m rows 4 m apart, 2.5 m above the crop
#   1 NAV_TAKEOFF 5 m              2 DO_SET_RESUME_REPEAT_DIST 2 m
#   3 DO_CHANGE_SPEED 6 m/s        4 NAV_WAYPOINT row 1 start (Terrain frame, 2.5 m)
#   5 DO_SPRAYER 1                 6 DO_CHANGE_SPEED 4 m/s
#   7 NAV_WAYPOINT row 1 end       8 DO_SPRAYER 0     then the same for rows 2-6
#   NAV_WAYPOINT home 5 m at 6 m/s, NAV_LAND
param set WP_SPD 4              # m/s along the rows (was WPNAV_SPEED 400)
param set WP_RADIUS_M 1         # m: how close counts as reached (was WPNAV_RADIUS 100)
param set WP_RFND_USE 1         # missions follow the radar height (was WPNAV_RFND_USE)
param set MIS_RESTART 0         # back in AUTO after a refill, it resumes instead of starting over
mode LOITER
arm throttle                    # AUTO cannot arm by itself
mode AUTO

Meet the spray drone

An agricultural spray drone has one job: put a measured dose of liquid on every square metre of a field and nowhere else. This one carries 10 L. Six 30-inch props on 900 mm arms lift 33 kg at take-off, and a Cube Orange+ runs ArduCopter, which flies the rows of a survey grid in AUTO. Two RTK receivers place it to about 2 cm and take the heading from the line between their antennas, so the rows sit exactly one swath apart and no steel shed can upset a compass. A radar under the nose holds it 2.5 m above the crop as the ground rises and falls. ArduPilot's sprayer runs the pump in proportion to the ground speed, so the dose stays the same when it slows for a turn, and the mission switches it on at the start of each row and off at the end. With six motors, the mixer can hold it level on five for long enough to land, if there is thrust to spare. Pick the parts, build it, run the bench checks (a pump test among them), then fly the rows by hand or let AUTO spray the field.

Practice task

Fly the field in Loiter first: take off to 5 m, come down to 2.5 m at the west end of the first row, fly it east at about 4 m/s, step 4 m north at the end and fly back. The drone is heavy and slow to stop (25° of lean, soft accelerations), so start every turn early. Keep clear of the trees on the west side and the power line on the east side, then bring it home and land. Then switch to AUTO and watch the pump go on and off at the row ends. On a real build: a smoke stopper on the first plug, the motor test with the props off (A at the front right, then clockwise), the accelerometer calibration, a pump test with clean water to measure the flow, an RTK fix and a GPS-yaw check outdoors, every PreArm message cleared, and a first hover low over open ground with nobody near the props.

Build a 10 L spray drone, test its pump and GPS yaw, then spray six rows of a field

Category

Parts

Cost

Electrical

$4,050

Mechanical

$1,180

Total (approx.)

$5,230

# ArduCopter 4.7.2 on a Cube Orange+: hexa X, six Hobbywing X8 units on MAIN 1-6, power brick on POWER1 param set FRAME_CLASS 2 # Hexa param set FRAME_TYPE 1 # X: M1 right, M2 left, M3 front left, M4 rear right, M5 front right, M6 rear left param set SERVO1_FUNCTION 33 # MAIN 1: Motor1 param set SERVO2_FUNCTION 34 # MAIN 2: Motor2 param set SERVO3_FUNCTION 35 # MAIN 3: Motor3 param set SERVO4_FUNCTION 36 # MAIN 4: Motor4 param set SERVO5_FUNCTION 37 # MAIN 5: Motor5 param set SERVO6_FUNCTION 38 # MAIN 6: Motor6 param set MOT_PWM_TYPE 0 # Normal PWM: the X8 takes 1100-1940 us, no DShot, no throttle calibration param set MOT_PWM_MIN 1050 # Hobbywing's numbers for open-source autopilots param set MOT_PWM_MAX 1950 param set MOT_SPIN_ARM 0.08 # armed idle: 30-inch props turn slowly and hit hard param set MOT_HOVER_LEARN 2 # learn the hover throttle and save it in MOT_THST_HOVER param set INS_HNTCH_ENABLE 1 # harmonic notch; refresh the parameters to see the rest param set INS_HNTCH_MODE 1 # follow the throttle: PWM ESCs report no rpm param set INS_HNTCH_FREQ 80 # Hz: about 2400 rpm x 2 blades at hover param set BATT_MONITOR 4 # analog voltage and current from the power brick param set BATT_CAPACITY 22000 # mAh param set AHRS_ORIENTATION 0 # Cube arrow to the nose; 4 = Yaw180 if it points back # FRAME_CLASS, the SERVOn_FUNCTIONs, INS_HNTCH_ENABLE and AHRS_ORIENTATION take effect after a reboot

# The 900 MHz radio on TELEM1, the radar on TELEM2, the two F9P receivers on GPS1 and GPS2 param set SERIAL1_PROTOCOL 2 # MAVLink2: telemetry out, RTK corrections in param set SERIAL1_BAUD 57 # 57600 param set SERIAL2_PROTOCOL 9 # Rangefinder param set SERIAL2_BAUD 115 # 115200 for the US-D1 param set RNGFND1_TYPE 11 # USD1_Serial: the Ainstein US-D1 radar param set RNGFND1_ORIENT 25 # looking down param set RNGFND1_MIN 0.5 # m: the radar reads nothing closer (was RNGFND1_MIN_CM) param set RNGFND1_MAX 45 # m param set SERIAL3_PROTOCOL 5 # GPS1 param set SERIAL4_PROTOCOL 5 # GPS2 param set GPS1_TYPE 17 # u-blox moving-baseline base: the front antenna param set GPS2_TYPE 18 # u-blox moving-baseline rover: the rear antenna param set GPS_AUTO_CONFIG 1 # the Cube configures both F9Ps param set GPS_AUTO_SWITCH 1 # use the better one; never 2 (blend) with a moving baseline param set GPS1_POS_X 0.17 # m forward of the centre of gravity param set GPS1_POS_Y -0.15 # m: ArduPilot's y points right, so masts on the left are negative param set GPS2_POS_X -0.17 param set GPS2_POS_Y -0.15 param set EK3_SRC1_YAW 2 # heading from the two antennas, not a compass param set COMPASS_USE 0 # steel sheds and a 450 A bus: leave the compass out param set GPS_INJECT_TO 127 # RTK corrections to both receivers

# The sprayer: enable it, refresh the parameters (the others stay hidden until it is on), then set it up param set SPRAY_ENABLE 1 param set SERVO9_FUNCTION 22 # AUX 1: SprayerPump param set SPRAY_PUMP_RATE 10 # % of full pump per m/s of ground speed: 40 % at 4 m/s param set SPRAY_PUMP_MIN 0 # %: nothing when it stops param set SPRAY_SPEED_MIN 100 # cm/s: no spray below 1 m/s (still centimetres in 4.7) param set RC7_OPTION 15 # channel 7 switch: Sprayer Enable; high while disarmed = pump test param set SERVO9_MIN 1000 # the pump driver's PWM range, from its manual param set SERVO9_MAX 2000

# Radio lost, ground station lost, battery low and critical, a fence round the farm, every pre-arm check param set FS_THR_ENABLE 1 # RC lost: RTL param set FS_GCS_ENABLE 1 # no ground-station heartbeat for 5 s: RTL param set BATT_LOW_VOLT 42 # 3.5 V per cell x 12 under load param set BATT_LOW_MAH 6600 # or 30 % of the 22000 mAh left param set BATT_FS_LOW_ACT 2 # low: RTL (FS_BATT_ENABLE no longer exists) param set BATT_CRT_VOLT 40.8 # 3.4 V per cell param set BATT_FS_CRT_ACT 1 # critical: land where it is param set BATT_ARM_VOLT 48 # 4.0 V per cell: take off only on a fresh pack param set FENCE_ENABLE 1 param set FENCE_TYPE 7 # max altitude + circle + polygon (the field edge) param set FENCE_ALT_MAX 30 # m param set FENCE_RADIUS 300 # m round home param set ARMING_SKIPCHK 0 # skip no pre-arm check (4.7; was ARMING_CHECK 1)

# Stabilize: self-levelling, the throttle stick is the motors. The last resort if the GPS or the radar goes param set ATC_ANGLE_MAX 25 # max lean in every mode, degrees: 33 kg of water and drone swings hard mode STABILIZE

# AltHold: the throttle stick asks for a climb rate; over crop the radar holds the height above it param set PILOT_SPD_UP 2.5 # m/s at full stick (was PILOT_SPEED_UP 250) param set SURFTRAK_MODE 1 # surface tracking: follow the ground the radar sees mode ALT_HOLD

# Loiter: RTK holds the position to a few centimetres, GPS yaw holds the heading param set LOIT_SPEED_MS 8 # m/s at full stick (was LOIT_SPEED 800) param set LOIT_ACC_MAX_M 3 # m/s/s: gentle with a full tank sloshing (was LOIT_ACC_MAX 300) mode LOITER

# Return to launch: climb to 12 m over the trees and the power line, fly home, land # The pump does NOT stop on a mode change: DO_SPRAYER 0 ends every row, or flip the sprayer switch off param set RTL_ALT_M 12 # m (was RTL_ALT 1200) param set RTL_SPEED_MS 6 # m/s home (was RTL_SPEED 600) param set RTL_ALT_FINAL_M 0 # 0 = land at home param set LAND_SPD_MS 0.5 # m/s for the last metres mode RTL

# The spray mission from a survey grid: six 36 m rows 4 m apart, 2.5 m above the crop # 1 NAV_TAKEOFF 5 m 2 DO_SET_RESUME_REPEAT_DIST 2 m # 3 DO_CHANGE_SPEED 6 m/s 4 NAV_WAYPOINT row 1 start (Terrain frame, 2.5 m) # 5 DO_SPRAYER 1 6 DO_CHANGE_SPEED 4 m/s # 7 NAV_WAYPOINT row 1 end 8 DO_SPRAYER 0 then the same for rows 2-6 # NAV_WAYPOINT home 5 m at 6 m/s, NAV_LAND param set WP_SPD 4 # m/s along the rows (was WPNAV_SPEED 400) param set WP_RADIUS_M 1 # m: how close counts as reached (was WPNAV_RADIUS 100) param set WP_RFND_USE 1 # missions follow the radar height (was WPNAV_RFND_USE) param set MIS_RESTART 0 # back in AUTO after a refill, it resumes instead of starting over mode LOITER arm throttle # AUTO cannot arm by itself mode AUTO

Meet the spray drone

Practice task

Build a 10 L spray drone, test its pump and GPS yaw, then spray six rows of a field

Agricultural spray hexacopter

Design it

Calculated for this build

Checks

Cost

Build it

Try a real mistake

Selected part

Parts in the box

Wiring

Safety tests

Smoke stopper test

Motor test (props off)

Accelerometer calibration

Pump test (disarmed)

RTK fix and GPS yaw

Pre-arm checks

MAVProxy console

Configuration snippets

Frame, motor outputs and power after the build

Radio, radar and RTK after the build

The sprayer after the build

Failsafes, fence and pre-arm checks after the build

Stabilize for Stabilize

AltHold for AltHold

Loiter for Loiter

Return to launch for RTL

AUTO: the spray mission for AUTO spray

Check yourself · Fit the power distribution

Check yourself · Fit the RTK masts

Check yourself · Fit the boom

Check yourself

Meet the spray drone

Practice task

Agricultural spray hexacopter

Design it

Calculated for this build

Checks

Cost

Build it

Try a real mistake

Selected part

Parts in the box

Wiring

Safety tests

Smoke stopper test

Motor test (props off)

Accelerometer calibration

Pump test (disarmed)

RTK fix and GPS yaw

Pre-arm checks

MAVProxy console

Configuration snippets

Frame, motor outputs and power after the build

Radio, radar and RTK after the build

The sprayer after the build

Failsafes, fence and pre-arm checks after the build

Stabilize for Stabilize

AltHold for AltHold

Loiter for Loiter

Return to launch for RTL

AUTO: the spray mission for AUTO spray

Check yourself · Fit the power distribution

Check yourself · Fit the RTK masts

Check yourself · Fit the boom

Check yourself

Meet the spray drone

Practice task