Troubleshooting

8.3 In-flight warnings

While it is in flight the eBee can generate two types of errors: warnings andfailures.

In-flight warnings occur when there is an event that requires user attention but

does not compromise the drone’s ability to continue flying.

When an In-flight warning is activated the warning will appear in yellow in eMotion and cause the ‘WARNING’ button in the Control Bar to change to ‘ACK WARNING’, turn yellow and activate. The drone will then perform a Security action depending on the active In-flight warning. Some In-flight warnings simply need to

be acknowledged by clicking on the ‘ACK WARNING’ button. Others require action by the user before the warning is cleared and the drone can return to full

functionality. The full list of possible In-flight warnings and required User actions

can be found in table 5 on the following page.

The In-flight warnings marked with a ∗can have their Security actions disabled,

whereas the In-flight warnings marked with a ∗∗ can have both the warning and

the Security action disabled. See section ‘Flight Parameters tab’ on page 123 for

instructions on disabling warnings and Security actions.

Caution: The Security action for most In-flight warnings is to fly back

to the Home waypoint (if Circular landing is selected) or the Home

waypoint(if Linear landing is selected). As soon as this Security action

is triggered the drone will fly in the direction of the selected landing

waypoint while climbing or descending to the waypoint’s altitude.

It is thus important to ensure that there are no obstacles above the

altitude of the selected landing waypoint within the entire flight area

to prevent a collision resulting from this Security action.

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Table 5: In-flight warnings

eMotion text Description and Security action

Failure occurred:

(failure

description)

This warning ensures that the user is aware that a

Critical failure has occurred even if it is no longer active57.

Security action: The eBee flies towards the Home

waypoint at an altitude defined by the Home waypoint’s Change altitude parameter (by default, set to

‘Highest’).

User action: Ensure that the failure condition is no

longer present before acknowledging the error and

continuing normal operation.

Low battery The remaining battery level is too low to continue the

flight plan.

Security action: The eBee flies towards the Home

waypoint at an altitude defined by the Home waypoint’s Change altitude parameter (by default, set to

‘Highest’) and automatically initiates an expedited

landing procedure (without performing a full wind

estimation) once it reaches the waypoint.

User action: Land as soon as possible. Re-charge the

drone battery before performing another flight.

57 see section ‘Critical failures’ on page 163 for a description of possible Critical failures

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Troubleshooting

Drone flight log

malfunction

There is an error saving data to the on-board memory card which will prevent the images from being

geo-tagged. Images may still be geo-tagged using

the eMotion Flight Log file but may be less precise.

Security action: The drone continues normal flight.

User action: Land as soon as possible. Once on the

ground, connect to the on-board memory card as described in section ‘Importing images and flight data’

on page 50 and re-format the memory card.

Flight controller

malfunction

The flight controller has encountered an unexpected

state, such as an incorrect waypoint type.

Security action: The drone flies towards the Home

waypoint at an altitude defined by the Home waypoint’s Change altitude parameter (by default, set to

‘Highest’).

User action: Land as soon as possible and re-start

the drone. If the problem persists, contact your eBee

reseller.

Camera sync

malfunction

There is a problem with the wiring of the on-board

camera.

Security action: If required parameter set in the

Flight Parameters tab, the drone flies towards the

Home waypoint at an altitude defined by the Home

waypoint’s Change altitude parameter (by default,

set to ‘Highest’). Otherwise it continues its mission

without taking further images.

User action: Land as soon as possible and re-start

the drone. Reset the camera settings as described

in section ‘Resetting default camera settings’ on

page 166.

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Maintenance, Repair and Troubleshooting

Camera power

malfunction

The camera is no longer responding, most likely because it is no longer powered.

Security action: If required parameter set in the

Flight Parameters tab, the drone flies towards the

Home waypoint at an altitude defined by the Home

waypoint’s Change altitude parameter (by default,

set to ‘Highest’). Otherwise it continues its mission

without taking further images.

User action: Land as soon as possible. Check the cable connection between the camera and the drone

and charge all the batteries before performing another flight.

Barometer

malfunction

The barometer used to sense the current altitude is

malfunctioning.

Security action: The drone flies towards the Home

waypoint at an altitude defined by the Home waypoint’s Change altitude parameter (by default, set

to ‘Highest’) using altitude calculated from GPS signals only, potentially causing large fluctuations in altitude.

User action: Land as soon as possible and perform

Check 3 in section ‘Full airframe and sensor inspection’ on page 139.

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Troubleshooting

Motor

malfunction

The motor is drawing too little or too much current.

This may be caused by damaged wires or connectors

leading to the motor or by sand or other debris within

the motor.

Security action: The drone attempts to re-start the

motor. If the first attempt fails a Failure: Motor malfunction Critical failure is announced58.

User action: Land as soon as possible and perform

Check 1 in section ‘Full airframe and sensor inspection’ on page 139.

Battery

malfunction

The sensor used to measure the battery voltage and

current is registering invalid values, indicating that

the sensor is de-calibrated or damaged.

Security action: The drone flies towards the Home

waypoint at an altitude defined by the Home waypoint’s Change altitude parameter (by default, set to

‘Highest’).

User action: Land as soon as possible and re-start

the drone. If the problem persists, contact your eBee

reseller.

58 see section ‘Critical failures’ on page 163

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Maintenance, Repair and Troubleshooting

Airspeed

malfunction

The differential pressure sensor used to measure airspeed is registering invalid values. This may be due

to a damaged sensor or to a clogged pitot probe.

Security action: The drone flies towards the Home

waypoint at an altitude defined by the Home waypoint’s Change altitude parameter (by default, set to

‘Highest’) at a constant thrust value instead of controlled speed, potentially resulting in low or high

flight speeds depending on wind. Once it reaches the

Home waypoint it initiates a landing procedure.

User action: Try to provide a maximum amount of

approach sectors to ensure that the drone can land

against the direction of the wind. Land as soon as

possible and perform Check 4 in section ‘Full airframe

and sensor inspection’ on page 139.

Low airspeed Detected airspeed is unusually low or close to zero.

This may be due to a collision with the ground or a

clogged airspeed sensor.

Security action: The drone shuts off its motor and

tries to continue its mission.

User action: If the warning is due to a clogged airspeed sensor it may be due to moisture in the air.

Try commanding the drone to descend closer to the

ground and out of any cloud cover.

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Troubleshooting

Overspeed Detected airspeed is unusually high, possibly due to

a loss of control.

Security action: The drone applies a 50% reverse

thrust to try to slow down.

User action: Keep track of the drone’s position in

case it is unable to slow back down to a regular airspeed.

Ground sensor

malfunction

The ground sensor used to detect the proximity of

the ground is malfunctioning.

Security action: The drone continues normal flight.

User action: Land as soon as possible and perform

Check 5 in section ‘Full airframe and sensor inspection’ on page 139.

Wings detection

malfunction

The sensor used to detect the presence of the wings

malfunctioning.

Security action: The drone continues normal flight.

User action: Land as soon as possible and inspect

the wing struts as described in section ‘Preparing the

eBee for flight’ on page 30.

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Maintenance, Repair and Troubleshooting

Temperature out

of working levels

The temperature sensor on the drone is registering

internal temperatures of less than -50◦ C or more

than 90◦ C. This may occur in extremely hot or cold

environments or if the on-board autopilot is damaged.

Security action: The drone flies towards the Home

waypoint at an altitude defined by the Home waypoint’s Change altitude parameter (by default, set to

‘Highest’).

User action: Land as soon as possible. If the outside temperature is above 35◦C or below -10◦C, disconnect the battery and wait until the temperature

changes to within these limits.

Above working

area ceiling

The drone has passed the vertical boundary of the

working area, defined by the working area ceiling.

This may occur if waypoint altitudes are set close to

or outside the working area or due to strong wind.

Security action: The drone flies towards the Home

waypoint at an altitude defined by the Home waypoint’s Change altitude parameter (by default, set to

‘Highest’). It also turns off its motor as long as it remains above the working area ceiling.

User action: Limit the altitude of all waypoints to

less than the working area ceiling.

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Troubleshooting

Out of working

area radius

The drone has passed the lateral boundary of the

working area, defined by the working area radius.

This may occur if waypoints are set close to or outside

of the working area or due to strong wind.

Security action: The drone flies towards the Home

waypoint at an altitude defined by the Home waypoint’s Change altitude parameter (by default, set to

‘Highest’).

User action: Limit the planned flight path within the

working area boundaries.

Far outside of

working area

The drone has passed far outside of the working area.

This may be caused by very high winds or due to mechanical failure.

Security action: The drone tries to orient itself in the

direction of the Home waypoint and begins descending immediately until it lands on the ground or returns within the working area.

User action: Keep track of the location of the drone

during landing. If the drone lands outside of view follow the instructions in section ‘Losing and locating

your eBee in the field’ on page 167.

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Maintenance, Repair and Troubleshooting

Poor GPS

coverage∗

GPS signal coverage is low. This may be due to mountains or tall buildings blocking satellite signals. If coverage degrades any more a Critical failure will be activated and an emergency landing will be initiated59.

Security action (if enabled): The drone flies towards the Home waypoint at an altitude defined by

the Home waypoint’s Change altitude parameter (by

default, set to ‘Highest’).

User action: If this occurs once or twice, click ‘ACK

WARNING’ and continue normal flight. If this warning

appears more often, land as soon as possible andwait

for better conditions for satellite signal reception. Alternatively, move away from objects that may disturb

satellite signals such as mountains or cellular antennas.

Data uplink lost∗∗

(if enabled)

This warning occurs if the eBee does not receive any

data from eMotion for more than 30 s. This can be

due to a large distance between drone and ground

station, a problem with the USB ground modem, antenna positioning or interference. .

Security action (if enabled): The drone flies towards the Home waypoint at an altitude defined by

the Home waypoint’s Change altitude parameter (by

default, set to Highest).

User action: Try to improve radio signal quality by

following the instructions in section ‘Improving radio

signal communication’ on page 166.

59 see section ‘Critical failures’ on page 163

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Troubleshooting

Ground proximity

detected∗∗

(if enabled)

The ground sensor on the drone has detected a

ground height above the ground of less than 30 m

during normal flight. Note: this feature should not

be depended on for avoiding obstacles, as the

ground sensor may fail to detect obstacles in certain environmental conditions60.

Security action (if enabled): The drone circles the

current position while climbing to an altitude of 60 m

above the detected ground height. Once this altitude

is reached the drone continues towards the next waypoint but sets the waypoint’s target altitude at 60 m

above the last detected ground height.

User action: Ensure that there are no obstacles such

as hills or buildings higher than the waypoints of your

flight plan.

Ground proximity

not detected

landing precision

decreased∗∗

The ground sensor on the eBee was unable to detect

the proximity of the ground during a Linear landing

procedure. This may be due to an obstruction in the

sensor, low ambient light or low contrast in the environment61.

Security action: The drone continues the Linear

landing procedure but will initiate its final brake at

an estimated altitude of 20 m instead of 3 m (assuming the Linear landing location is at the same altitude

at the Take-off location), resulting in decreased precision in the landing location.

User action: Be ready for the drone to overshoot

its planning Linear landing location by preparing a

larger obstacle-free zone around the location.

60 see section ‘Linear landing’ on page 72

61 see section ‘Linear landing’ on page 72

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Maintenance, Repair and Troubleshooting

Back wind,

landing precision

decreased∗∗∗

(in blue)

There are no approach sectors available against the

direction of the wind. The eBee has calculated a Linear landing approach direction in the direction of the

wind.

Security action: The eBee continues normal flight.

User action: Add a new approach sector against the

direction of the wind, if possible, abort the landing

and try landing again. If not, be ready for the eBee

to overshoot its planning Linear landing location by

preparing a larger obstacle-free zone around the location.

Strong wind∗The wind is too strong for the eBee to navigate safely.

Security action (if enabled): The eBee flies towards

the Home waypoint at an altitude defined by the

Home waypoint’s Change altitude parameter (by default, set to ‘Highest’).

User action: Land as soon as possible and wait for

better flight conditions.

Cannot maintain

altitude

The eBee cannot maintain the altitude that is commanded by the flight controller. This may be due to a

damaged motor, airframe or ailerons or a strong vertical wind.

Security action: The drone continues normal flight.

User action: If the condition persists during a flight,

land and wait for the wind to decrease, as explained

in section ‘Weather check’ on page 29. If the problem occurs in low-wind conditions perform Check 2

in section ‘Full airframe and sensor inspection’ on

page 139.

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Troubleshooting

Pitch or Roll

instability

The orientation sensors on the eBee detected unusually high pitch or roll values even after performing

stabilization. This may be due to strong winds or

damaged airframe.

Security action: The drone continues normal flight

while trying to stabilize the pitch as much as possible.

User action: If the condition persists during a flight,

land and wait for the wind to decrease, as explained

in section ‘Weather check’ on page 29. If the problem occurs in low-wind conditions perform Check 2

in section ‘Full airframe and sensor inspection’ on

page 139.

8.4 Critical failures

A critical failure is an error that occurs in flight that prevents the continuation

of normal flight. This is the most serious type of error that can occur with the

eBee, and is indicated in red in eMotion. The ‘WARNING’ button in the Control Bar

changes to ‘CRITICAL FAILURE’, becomes red and cannot be acknowledged. When

a critical failure occurs flight is aborted and the drone initiates an Emergency action in which it is immediately directed to the ground. The Emergency action for

each Critical failure is designed to minimize the airspeed and thus impact energy

with the ground using the sensors that are still functioning.

Table 6 on the following page describes the critical failures that may occur and

what action is taken by the drone. In some cases it may be possible to manually

control the drone using the remote control62. If such a critical failure occurs that

results in an Emergency landing we recommend that you keep track of the drone’s

62 see section ‘Manual control of the eBee’ on page 127

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Maintenance, Repair and Troubleshooting

last known position in the air and in eMotion if possible and follow the instructions

in section ‘Losing and locating your eBee in the field’ on page 167.

Table 6: Critical failures

eMotion text Description and Emergency action

Failure: loss of GPS

signals

Your eBee can no longer calculate its position, making it impossible for it to know where it is and thus to

navigate.

Emergency action: The drone turns off its motor,

sets a bank angle and glides in a large circle towards

the ground. If there is a strong wind the drone may

be pushed far from its current position. If satellite signals are re-acquired the drone will abort the landing

procedure and go to the Home waypoint.

Failure: empty

battery

The battery is completely empty.

Emergency action: The drone turns off its motor

and glides towards the ground in the direction of the

Home waypoint. This error is always preceded by a

Low battery In-flight warning.

Failure: INS

malfunction

There is a failure with the orientation sensors which

makes it impossible for the drone to stabilise itself

and thus initiate a gliding emergency landing.

Emergency action: The drone turns off its motor

and fully deflects its ailerons which results in an uncontrolled descent with limited impact energy (deep

stall or spin).

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Troubleshooting

Failure: motor

malfunction

The motor is not working even after an attempted

re-start commanded by a Motor malfunction In-flight

warning.

Emergency action: The drone orients itself in the direction of the Home waypoint and glides towards the

ground while continuously trying to re-start the motor. If motor re-start is successful the drone cancels

the landing and flies towards the Home waypoint at

an altitude defined by the Home waypoint’s Change

altitude parameter (by default, set to ‘Highest’).

Failure: CPU OverloadThe autopilot processor is overloaded and can no

longer control flight. The drone turns off its motor

and fully deflects its ailerons which results in an uncontrolled descent with limited impact energy (deep

stall or spin).

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Maintenance, Repair and Troubleshooting

8.5 Resetting default camera settings

In case of unwanted configuration changes, the camera can be re-configured to

a suitable state. Please refer to your camera user manual for the procedure. You

can find camera manuals in our Knowledge Base within my.senseFly63

8.6 Improving radio signal communication

You may occasionally lose the data connection between eMotion and your eBee

while in the field. Whether there is a loss in uplink or downlink communication,

the drone will continue flying along its Flight Plan and should re-establish the

connection as it flies closer to the base station or changes direction.

If the drone stops receiving messages from eMotion (uplink direction) for more

than 30 s you will see a ‘Data uplink lost’ In-flight warning appear in eMotion. If for

safety reasons you would like the eBee to automatically return to the Home waypoint when this warning appears, select the corresponding option in the Flight

Parameters tab64.

If there are no more messages received by eMotion from the drone (downlink direction), a ‘Data downlink lost’ message will appear in eMotion. If there is still an

active uplink connection you may still command your drone to return to the Home

waypoint using the Control Bar.

Data connection range can be effected by many external factors such as antenna

height, terrain and obstacles or radio interference. We recommend the following

tips to improve the range of your connection in the field:

1. Place the USB ground modem as high as possible (for example, on top of a

car, ladder or nearby building). A height of at least 2 m is recommended.

2. Ensure that the USB ground modem’s antenna is pointing straight up.

3. Disable any 2.4 GHz-based communication devices (or put them into ‘Airplane mode’) in the vicinity of the USB ground modem. This includes all

63 http://my.sensefly.com

64 see section ‘Flight Parameters tab’ on page 123 for more details

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Troubleshooting

Wifi and Bluetooth devices such as the ground station computer or mobile

phones.

The strength of the connection between the drone and eMotion is indicated in

the Flight Monitoring tab65. The three LEDs next to the antenna on the ground

modem also indicate the strength of the connection. The connection is strongest

when all three LEDs are a solid red, and weakest when a single LED is blinking.

8.7 Losing and locating your eBee in the field

We recommend that you write your address and phone number on your eBee (by

putting your business card on top of the camera for example) in case it gets lost

and subsequently found by a third party. In case you lose your drone in the field

for whatever reason, whether from a loss of communications, a Critical failure or

an accidental collision, use the following steps to try to recover it:

1. Do not disconnect the connection in eMotion! If it is simply out of communication range the drone should reconnect automatically as it returns to

the Home waypoint after completing its mission.

2. Note the last known location of the drone in eMotion by printing the screen

or writing down the location displayed in the Flight Monitoring tab.

3. Move towards this last known direction with the computer running eMotion in the hope of regaining a connection. Be sure to take the remote control with you as well.

4. If you have reached the last known location of your drone and have not yet

found it, turn on the remote control.

5. Try moving both the control sticks around. If the drone is within range it

may start making noise with its main motor or servo motors.

6. Try moving downwind from the last known location in case the drone was

pushed by the wind while still in the air.

65 see section ‘Flight Monitoring tab’ on page 98

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Maintenance, Repair and Troubleshooting

8.8 Reporting a problem with your eBee

If there is a problem with your eBee, whether it is a software malfunction, damaged airframe or any other problem, we recommend the following actions:

1. If there is an error message displayed in eMotion, begin by checking section

‘Troubleshooting’ on page 145 to see if there is a solution to the particular

message.

2. Check our Knowledge Base, part of my.senseFly66, to see if there is a solution to your problem.

3. If you have still not found a solution, contact your eBee reseller. Please include the following information with your inquiry:

• The serial number of your drone, in the format EB-XX-XXX. You can

find this number inside the battery enclosure.

• A short description of the problem.

• The Drone Flight Log file of the flight that had a problem67.

• The eMotion Flight Log file of the flight that had a problem. You can

find this file in the eMotion/logs/ directory which is created in My

Documents on Windows.

• Photos or video of the eBee airframe, if required.

Note: In order to provide support, senseFly may request the flight

log files for inspection.

66 http://my.sensefly.com

67 see section ‘Importing images and flight data’ on page 50 for information on retrieving this file from

the eBee

168
Part IV

Specifications
Specifications

1 Software requirements

eMotion has the following minimum software requirements:

Operating system Microsoft Windows 7 / 8

Hardware 1.6 GHz processor

2 GB RAM

500 MB free storage space

Screen recommended resolution: 1920×1080

visible outdoors

Postflight Terra 3D has the following minimum software requirements:

Operating system Microsoft Windows 7 / 8, 64-bit only

Hardware 1.6 GHz processor (2 GHz Intel i5/i7/Xeon recommended)

4 GB RAM (16 GB recommended for large projects)

10 GB free storage space (1 TB recommended for large

projects)

Screen min. resolution: 1024×768

170
Drone specifications

2 Drone specifications

Size Wingspan: 96 cm

Wing area: 0.25 m2

Weight without camera and battery approx. 0.42 kg (0.93 lbs)

Nominal take-off weight (approx.) eBee: 0.67 kg (1.48 lbs)

eBee Ag: 0.71 kg (1.56 lbs)

(with standard camera & battery)

Maximum take-off weight 0.75 kg (1.65 lbs)

Material EPP foam, carbon structure & composite parts

Battery 3-cell Lithium-Polymer (0.14 kg)

Nominal endurance (flight time)68 eBee: 50 minutes

eBee Ag: 45 minutes

(with standard camera)

Propulsion Electric brushless motor

Nominal static thrust: 0.63 kgf (6.2 N)

Nominal cruise speed 40-90 km/h (11-25 m/s or 25-56 mph)

Wind resistance up to 45 km/h (12 m/s)

Max. single flight coverage69 eBee: 12 km2(4.6 mi2)

eBee Ag: 10 km2(3.9 mi2)

(on a single battery charge)

68 can vary greatly depending on external factors such as wind, altitude change and temperature.

69 calculated based on the following test conditions: GSD of 30 cm (11.8 in) per pixel, no wind, moderate air temp. (18 C/64.4 F), new fully-charged battery, flight altitude of 1,000 m (3,280 ft) above

ground & take off at approx. sea level from centre of coverage area.

171
Specifications

Communication devices Ground modem:

• Frequency: 2.4 GHz

• Range70: approx. 3 km

• Certification: FCC Part 15.247, IC RSS210, CE

Remote control:

• Frequency: 2.4 GHz

• Range: approx. 1 km

• Certification: CE, FCC

Navigation Up to 50 waypoints

GSD (per pixel) eBee: Down to 1.5 cm (0.6 in)

eBee Ag: Down to 2 cm (0.8 in)

Absolute horizontal eBee (with GCPs): Down to 3 cm (1.2 in)

accuracy eBee (no GCPs): 1 to 5 m (3.3 to 16.4 ft)

eBee Ag (with GCPs): Down to 4 cm (1.6 in)

eBee Ag (no GCPs): 1 to 5 m (3.3 to 16.4 ft)

Absolute vertical eBee (with GCPs): Down to 5 cm (2.0 in)

accuracy eBee (no GCPs): 2 to 5 m (6.6 to 16.4 ft)

eBee Ag (with GCPs): Down to 7 cm (2.8 in)

eBee Ag (no GCPs): 2 to 5 m (6.6 to 16.4 ft)

Relative orthomosaic/ 1-3 times GSD

3D model accuracy

Carry case dimensions 55 x 45 x 25 cm (21.6 x 17.7 x 9.8 in)

70 can vary greatly depending on external factors such as cruise altitude, presence of obstacles and

radio-frequency interference.

172
Glossary

AMSL Above Mean Sea Level

Your eBee’s altitude can be shown and set in eMotion using ATO or AMSL.

Your drone uses the EGM96 mean sea level standard for navigation.

ATO Above the Take-off Altitude

Your eBee’s altitude can be shown and set in eMotion using ATO or AMSL.

Altitudes in ATO are relative to the place your eBee started its motor just

before take-off.

DSM Digital Surface Model

A 3D digital representation of a surface.

FTDI Future Technology Devices International

A Scottish semiconductor device company specialising in Universal Serial

Bus (USB) technology. FTDI cables allow serial connections through a USB

cable. eMotion uses FTDI technology to connect to the ground modem.

You can often connect a computer to a GNSS base station using FTDI.

geo-reference A data point associated with a specific location on the earth’s surface.

GSD Ground Sampling Distance

The distance measured on the ground between pixel centres in an image

or DSM. The smaller the GSD, the higher the spatial resolution of the image.

For example, a GSD of 5 cm means that one pixel in the image represents

5 cm on the ground.

mosaic A single map or terrain model created from several map sections that

have been placed side-by-side and merged together.

orthomosaic A single, corrected image constructed either from several images

taken from different angles, or from several orthophotos. Distortions due
to different camera positions, ground curvature and relief are corrected for

so that the image displays accurately in the given map projection.

photogrammetry A technique inwhich measurements takenfrom photographs

are used to reconstruct a 3D surface or a series of points in space.

point cloud A set of data points within a coordinate system.

rayCloud Afeature unique to Postflight Terra3Dthat combines the 3D point cloud

with the original images. Multi ray matching with the rayCloud extends the

stereo view triangulation and increases the accuracy of 3D point estimates

while providing a full understanding of 3D results.

triangle model An approximate representation of a surface, constructed from

connected triangles.