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NextCore RN50 User Guide Version 1.1 1 Revisions 3

1.1 Documentation 3

1.2 Software 3

1.3 Hardware 3

2 Introduction 4

3 Disclaimer 5

4 List of Items 5

4.1 Nextcore RN50 5

4.2 M600 Mounting Kit 5

4.3 Custom Pelican Hard Case 5

5 M600 Installation 6

5.1 Recommend Tools 6

5.2 M600 Configuration 6

5.2.1 Vibration Isolators 6

5.2.2 Power Installation 7

5.2.3 API Configuration 8

5.2.3.1 Cable Installation 8

5.2.3.2 API Settings Configuration 9

6 NextCore Installation 10

6.1 Standard Installation Workflow 10

6.2 Attaching the M600 mount kit 11

6.3 Antenna Installation 12

6.4 Mechanical Drawings 13

6.5 RN50 Pinout 13

6.6 Mounting the payload to an M600 14

7 Mission Planning 15

7.1 Manual vs Grid Flights 15

7.2 Key Considerations 15

7.3 Suggested operating parameters 17

7.4 Flight Planning with DJI GS Pro 18

7.4.1 Grid mission setup 18

8 Operating Payload 20

8.1 Standard Data Capture Workflow 20

8.2 Data Capture 20

8.2.1 Manual Capture 20

Version 1.1 NextCore RN50 User Guide 1

8.2.2 Auto Capture 21

8.3 Status Description 21

8.3.1 Led Status 22

8.3.2 Oled Status 22

9 NextCore Software 23

9.1 Basic information 23

9.1.1 Installation 23

9.1.2 Calibration 23

9.1.3 Data Management 23

9.1.4 Initial Interface 24

9.2 Live Telemetry & Data Download 24

9.3 Payload USB Control 24

9.4 Batch Process 24

9.5 Process Dataset 25

9.5.1 Standard Data Processing Workflow 25

9.5.2 Post Processing 26

9.5.3 Flight Line Selection 28

9.5.4 Fusion Settings 30

9.5.4.1 Fusion 32

9.5.4.2 Combined Decimation: 32

9.5.5 Export Settings 33

9.5.5.1 Export Paths 33

9.5.5.2 Export Options 33

9.5.5.3 Export Projections 34

9.5.5.4 Export Outputs 34

10 Additional Attachments 35

10.1 RGB Camera 35

11 Troubleshooting 36

11.1 Hardware OLED Errors 36

11.1.1 Line 1 36

11.1.2 Line 2 36

11.1.3 Line 3 37

11.1.4 Line 4 37

11.2 Flight Operation FAQ 39

11.3 Warranty Information 40


1 Revisions This section outlines the changelog of the RN50 product.

1.1 Documentation

Version Change Log Description

1.1 Initial User Guide release

1.2 Software

Version Change Log Description

3.1.7124.2188 Initial Nextcore release

1.3 Hardware

Hardware Version

Firmware Change Log Description

1.0.1 3.1.603 Initial RN50 release


2 Introduction

Congratulations on the purchase of your NextCore RN50

LiDAR Scanning unit. This guide is designed to demonstrate the

proper use for creating LiDAR point clouds using your

NextCore RN50 Platform attached to the DJI m600 UAV.

The guide assumes that you are an experienced operator of

UAV equipment and are familiar with the operations of the DJI

m600. You must operate in accordance with DJI m600 User

Guide at all times. In order to ensure your unit performs to its

specifications and remains operable, it is important that you

read through this User Guide carefully.

If you are in doubt regarding the contents of this user guide it is

important that you contact your distributor for clarification or

further training.

Thank you for your purchase, the staff at NextCore wish you all

the best in the operation of your unit.

Kind Regards,

Nick Smith

Chief Executive Officer


3 Disclaimer NextCore accepts no liability for damage or injury or any legal responsibility incurred directly

or indirectly from the use of this product or data created. The user shall observe the operating

guidelines of this unit and the guidelines of the equipment it is attached to at all times.

4 List of Items

4.1 Nextcore RN50 1x Payload

1x Power Adapter

1x 64GB USB Thumb Drive

4.2 M600 Mounting Kit 1x M600 Mounting Kit

1x Power and API Adapter

2x Antenna Booms

4x Vibration Isolators

4.3 Custom Pelican Hard Case 1x 1615 Air Pelican Hard Case

1x RN50 Tool Kit


5 M600 Installation

5.1 Recommend Tools - M2 Hex Driver

- M2.5 Hex Driver

- Thread Locker (either mid or high strength depending, recommended Loctite Blue 243)

5.2 M600 Configuration The Nextcore RN50 has been designed to suit the DJI M600 product. Whilst the RN50 is not

dependent on this product and can be used on other UAV’s please make sure to follow the

recommended user guide of both the desired UAV and the Nextcore product.

The following is an explanation on how to configure the M600 to carry the Nextcore product

and how to configure the DJI API port to enable the auto-capture feature. This section

assumes that you have the Nextcore RN50 M600 mounting kit. Please refer to the DJI M600

user guide and recommended specifications for more details.

5.2.1 Vibration Isolators


The M600 comes stock with a rigid mounting system. In order to attach the NextCore RN50

system to your M600, a set of vibration isolators are included in the mounting kit. These will

replace the rigid mounts of the M600. You can reuse the screws from your rigid mounts for

your vibration isolation mounts. Always remember to apply blue thread locker to these as they

can stay on your M600 and do not need to be removed with each install. The vibration isolators

tube mounting points are the same width and diameter as the rigid mounts and can be left on

your M600.

5.2.2 Power Installation

The NextCore RN50 system is designed to take power from the UAV. This reduces payload

weight and increases flight time compared to an integrated battery system. As such an inline

connector is provided with the system. The RN50 takes a 6S-LIPO input (20-26.2v). On the

M600 this can be tapped into via the XT30 connector between the M600 battery pack and the

landing gear. Simply add the inline connector. This can be left on the drone when the RN50 is

not attached to the system.

Note: Please ensure the power harness is clear from the landing retract system, if the wires

get caught in the mechanism it could cause a short fatally damaging both UAV and payload.


5.2.3 API Configuration

As part of the M600 mounting kit, an optional API connector is provided. This connector is for

the DJI A3 flight controller. This connection will enable the auto start capture feature of the

RN50 unit. This will start the capture of the system on flight arm and disarm (take off and land).

This cable and associated A3 setting can be left attached to the system and will not impede

with regular flight operations.

5.2.3.1 Cable Installation


Note: Do NOT use the Vcc pin. You might damage your payload onboard computer, A3 or

both.

To install this cable first remove the M600 top cover. This will expose the A3 flight controller.

Attach the provided Futaba servo connector to the API port of the A3. This connector should

be orientated so that the white lead is in position 1, red lead is in position 2 and the black

grounded lead is in position 3. Please note that the wrong orientation of this cable can cause

irreversible damage to the RN50 unit. The other end of this can be fed through the M600

frame to be exposed at the bottom ports of the system. This Futaba servo connector can then

be used in conjunction with the provided RN50 Molex connector.

5.2.3.2 API Settings Configuration

The API settings on the A3 will also need to be enabled to allow for API control of the payload.

Using DJI assistant 2, enable the API output under the SDK tab. The GPS output should also be

changed to 10Hz. Refer to the DJI A3 manual on how to upload these settings.

Note: Updating A3 firmware can cause the loss of settings and you may need to enable them

again.


6 NextCore Installation 6.1 Standard Installation Workflow

Note: Steps 1 and 2 of the standard installation workflow only need to be done on the initial

integration of the unit and can be left on the M600.

This section outlines how to install the NextCore RN50 onto an M600. The RN50 is designed

to fit onto the existing rail system of the M600 unit. Please make sure that the vibration

isolation mounts are attached to the M600 before continuing with this step. The API cable

should already be installed if you want to use the auto capture feature. Your RN50 system

should arrive with the M600 mounting system already assembled on the payload. If this is not

the case or you have bought the mounting solution after the initial unit please follow the next

step. If your mounting solution is attached you can go straight to the M600 mounting section.


6.2 Attaching the M600 mount kit

To assemble the mounting kit attach the aluminium mounting wings to both the centre 25mm

carbon fibre antenna boom and the 12mm carbon fibre mounting rails. Four 12mm tube

clamps are provided alongside eight M3x12 are provided to clamp positions (A). Two 25mm

tube clamps with M3x15 are provided for clamping position (B).

When assembling the M600 mounting kit it is important to make sure that the middle antenna

section is centred between the two wings. This will increase the accuracy of the IMU as it

depends on the fixed position of the primary antenna as seen in B. It is also important to centre

the 12mm clamps over the front wing of the RN50 as seen in A. The centre of mass is towards

the Lidar so mounting the tube clamps over the centre of mass will improve flight efficiency

and stability of the UAV. The easiest way to assemble this mounting kit is to first attach the two

mounting wings to the payload with the provided M3x20 screws as seen in C. Make sure that

these are hand tight and that thread locker is applied. Then attach the 25mm antenna boom

and then the 12mm mounting rails.


6.3 Antenna Installation

The NextCore RN50 system operates a dual antenna system in order to reliably define its

orientation. In order for this to happen two antennas need to be attached to the payload

system. The M600 mounting solution comes with mountable booms suitable for the M600

profile. Using the M600 mounting kit you need to attach the antennas attached to the carbon

fibre extension tubes. This is attached to a slip ring tube connector. This is a keyed connector,

when attaching the booms make sure that the antennas are facing the sky. In order to connect

the antenna to the payload two SMA breakouts on the top of the unit. It is important to

connect the forward antenna (Lidar side) to the primary connector and the back antenna to the

secondary antenna. Antennas are colour coded in order to avoid confusion. To follow the DJI

standard of orientation colouring the primary antenna is red whilst the secondary antenna is

green.

The antennas may be removed while the payload is installed on an M600, which allows for easy

transportation of the system.

Note: If antenna connections are around the wrong way it will result in an incorrect heading

leaving data capture invalid. Also the offsets from the RN50 unit to the antennas is very

specifically calibrated, changing this geometry will cause data issues.


6.4 Mechanical Drawings

The RN50 is connected to the M600 Mounting Kit through four M3 mounting holes located on

the top of the product. Screws must penetrate the RN50 with at least 15mm of thread from

the top of the plastic.

6.5 RN50 Pinout

Pin Function

1 VCC

2 GND

3 NC

4 API UART RXD

5 API UART TXD

6 Signal GND


The RN50 has a Molex Nano-Fit 105310 series connector. This connector is provided with

each purchase. Only use provided NextCore cabling when powering the payload. API

connections only apply to the A3 API auto-capture feature of the product. If this feature is not

desired then use only the power connector and not the dual power and API connector.

Note: Attaching a connector with the incorrect pinout can cause permanent damage to the

system.

6.6 Mounting the payload to an M600

To attach the unit to the M600 using the 12mm rails provided in the mounting kit. This will fit

into the vibration isolators circular opening. The best practice is to undo all clamps, insert one

side of the payload into the vibration isolators and then slide forward them back into the

opposite side. Once the payload is within the vibration isolators centre the payload so that the

small indicator lines on the 12mm tube rails fit within the circular clamps. Make sure to tighten

the vibration isolator clamps on all four corners. Apply thread locker to these to ensure that

the vibrations caused by the UAV will not loosen the screws.


7 Mission Planning

7.1 Manual vs Grid Flights It is highly recommended to fly any data capture mission with a set grid mission. Grid missions

ensure that all desired areas will be covered. It also reduces IMU error due to the somewhat

uniform nature of the flight characteristics. It is still possible to fly the unit in manual mode.

This may be done to get a higher point density over a key object or area. If flying in manual

mode please keep the UAV steady with a constant velocity and direction if possible.

7.2 Key Considerations

The key to getting good datasets is ensuring that the area to be scanned is well covered by the

flight. Getting good coverage means thinking about the aspect of the LiDAR sensor and making

sure you scan via lines that are parallel to features you want to extract.

A good flight is of at least a moderate duration >7 mins (this allows time for filters to settle and

produce better data). Each flight should include a few slow manoeuvres with pitch and roll in

each direction consistently for a few seconds. This may be a simple box pattern once up to

flight altitudes. This helps the filters settle and learn the pitch/roll offsets.

Smooth flight lines are required for a good dataset, preferably automated with a consistent speed.

Flight speed – the faster the flight speed the lower the point density, but good point density

can be produced up to a speed of 10m/s. Generally, it will be better to fly more flight lines at a

higher speed than slower sparser flight lines. Normal flight profiles do not require speeds

<5m/s, unless high density or vegetation penetration is required.

Flight line spacing should generally be as close as possible. Normally flight line spacing should

be around the flight height (circa 25-50m). If there is more vegetation or specific features to be

detected then flight lines should be closer together.


Flight height must be higher than obstacles around. Best practice for ensuring safe operation is

to fly a smaller drone (DJI Phantom 4, or DJI Mavic) and check for clearance at set altitudes. A

good dataset can be collected between 20m and 50m, usually, about 30-40m is best choice.

Flying lower concentrates data directly underneath the flight lines, but gets better side aspect

on vegetation and structures. Flying higher gets a more vertical aspect and better vegetation

penetration (esp off flight line centre), but flying too high can induce ranging errors and induce

IMU errors. 80m is a maximum altitude to get LiDAR returns.

Yawing should be avoided for the most part, mission grids should be flown with a consistent

heading (no yaw at end of lines). If for coverage reasons two aspects are required, do a grid

with one heading and then another grid at 90 degrees, with one yaw change between the two.

If including yaw during a manual flight, smooth consistent changes are preferred.

Optimal flight operation utilises the following parameters:

● Consistent flight height (AGL)

● Consistent UAV heading

In order to achieve this NextCore recommends flight mission planners that allow for terrain

following and single directional orientation. The NextCore team use the app Drone Harmony

https://droneharmony.com/ for mission planning, though other applications may be suitable.


https://droneharmony.com/

*A typical flight mission setup using Drone harmony to follow the terrain and maintain one

heading orientation during a flight.

Wind is a factor that can affect the accuracy of the data. Wind will cause the UAV to move

erratically to maintain a constant flight line on a grid mission. This erratic movement has an

effect on the accuracy of the data and should be avoided if maximum accuracy is desired.

Smooth consistent wind is not as problematic as gusty turbulent wind which will cause more

motion from the UAV.

Rain should be avoided as exposure to moisture may reduce the lifespan of the unit and void

the warranty.

Available Light is not a concern. The RN50 can effectively be used at night and any time of day

regardless of light availability. Consideration should be given to capturing data when the sun is

low (sunrise and sunset) as direct sunlight into the sensor may produce false points.

7.3 Suggested operating parameters

Parameter Recommended Maximum

Flight Height AGL (m) <40 metres 80 metres

Line Spacing (m) <30 metres 50 metres

Flight Speed (m/s) 5 m/s 10 m/s

Wind Speed (m/s) Calm <10 m/s (gust)


7.4 Flight Planning with DJI GS Pro An example mission setup is shown using the popular flight planning software DJI GS Pro. All

screenshots are from DJI GS Pro version 20.5 (8664) and are correct for that firmware version.

DJI GS pro is very common amongst photogrammetry missions and these settings can be

adapted to Lidar missions. This is am example data capture and is to be used only as a guide for

mission planning. Mission planning is very dependent on the desired deliverables needed. It is

best to practice with the RN50 on smaller datasets under different mission setting to

understand what settings are appropriate for the desired mission.

7.4.1 Grid mission setup

Start a new 3d mapping grid mission on the DJI GS pro app. Set the desired mission fence and

area. The camera mode is recommended as A7 or an equivalent camera. Make sure to change

the capture mode to ‘Capture at Equal Dist. Interval '. The height of the mission should be

within the recommended flight height. For this mission the height is 40m AGL. Flight speed is

controlled by the front overlap percentage of the advanced setting.


Under the advanced settings tab of the application ensure that the front overlap ratio is such

that your flight speed is within the recommended parameters. The side overlap is chosen to a

percentage in order to make sure that the distance between flight lines are within the

recommended spacing. For this mission the desired flight line spacing was 40m. Always change

the course angle to give the longest possible flight lines. This will reduce mission time and

increase IMU filter accuracies.


8 Operating Payload 8.1 Standard Data Capture Workflow

This section outlines the operation of the payload when attached to the scanning mount.

8.2 Data Capture The RN50 has two different types of data capture initiation. This includes a manual start/stop

capture and a flight controller enabled auto capture. A user can always initiate a manual

capture even when the auto capture is enabled and plugged in. To enable auto capture please

refer to the API configuration section within this user guide.

8.2.1 Manual Capture To start manually capturing data the system first needs to be in a state where it is ready to

capture. This occurs when there are no internal errors within the system.

When the two status leds on the display panel are green the system is ready to capture.

If for some reason the lights are presenting either as a constant red or yellow please refer to

the Status Description section below for more details.

Once these lights are green the system is ready to capture. To initiate a capture the user needs

to press the push button for half a second. This will start a capture, indicated by a blinking

green light on the display panel as well as the side led strips going green. If for any reason the

side led lights go red this indicates that there is an error with the data capture process. After

the mission has been flown the capture will need to be manually stopped. This is done by

pressing the button for half a second.


Once the capture is completed, the data will automatically start copying to the USB thumb

drive. On the completion of a capture the Lidar sensor will also be spun down. Once the RN50

has copied all of the data to the USB storage device it will remain in a steady state either ready

for another capture or to be shutdown. Note that if another capture is required the lidar will

have to be powered on again. This is done through simply pressing the push button. The lidar

will then power on, the user will have to wait until the lidar has established a connection before

they can reinitiate a data capture (~30 seconds - lights will go green again).

8.2.2 Auto Capture When using the auto capture feature of the RN50 the user does not have to interact with the

payload in any way while UAV is powered on. To achieve this the API cable must be connected

and the A3 must be set to the correct output (refer to the API Configuration section). This

feature will start a capture upon arming of the A3. As such it is important to wait until the

RN50 is presenting green lights before arming the A3. When the system is armed the data

capture will automatically occur. This will show a flashing green light as well as green side leds.

After the mission is flown and the system is disarmed the capture will automatically be turned

off and the system will copy the data of that capture to the USB storage device. The lidar will

also be powered down during the copy process. It will need to manually be powered on with a

push of the button before reflying the RN50. Arming the A3 when the system is not ready can

cause faulty data.

8.3 Status Description The RN50 is equipped with 3 status leds and an OLED display. These three Leds provide basic

system status in order to be seen from a distance. The OLED gives more complete data and

system information.


8.3.1 Led Status There are three status leds on the RN50 model. This includes two system leds attached to the

display panel as well as one led bar that covers both sides of the RN50. The display leds are

linked to internal systems.

● Led 1 indicates the status of the Lidar sensor as well as a general system indicator.

● Led 2 indicates the status of the GNSS receiver within the product.

● The side leds only change status when capturing to indicate whether the system is

outputting data correctly. If these leds are red it shows an error in the system that will

cause data collection issues and must be rectified.

Green Red Yellow Green Flash Yellow Flash

Blue Breath

Blue Solid

1 - “Lidar” System Ready

System Not Ready

Warning in System

Capturing data

correctly

Busy - Copying to USB

2 - “GNSS” GNSS Fix No GNSS Fix

Acceleration over Range

3 - “Capture” Capturing correctly

Error Capturing

Booting system

System ready

8.3.2 Oled Status

The system has a display oled to give more detail to the user. This is displayed on four lines of

text across the oled display.


Line Indicator

1 System State

2 Lidar Sensor

3 IMU / GNSS sensor

4 On board Storage / Flight telemetry

Information about various display strings can be found in the troubleshooting section of this

manual.


9 NextCore Software The section will outline the Nextcore software supplied with each unit. The nextcore software

is used to develop usable .las/ .laz files from the lidar sensor. This software requires an internet

connection to authenticate, post process the flight and download map data.

9.1 Basic information

9.1.1 Installation The nextcore software is provided with each payload with the accompanying USB. To install

this on your local machine all you have to do if copy over the folder with Nextcore Ground

Station and store it on your computer. It is recommended to copy the electronic Nextcore

Ground Station folder provided with each unit onto a known directory.

9.1.2 Calibration With each Nextcore unit an individual calibration file is provided “lidar.cali”. This is stored in

the same directory as the Nextcore Software. This will be the calibration default for processing

unless another calibration file is required. If this is the case the “lidar.cali” file will need to be

placed within the directory of the desired processing data. This will overwrite the default

calibration and use the new calibration file for this dataset only.

9.1.3 Data Management All datasets that are captured by the system are sorted under UTC time within a UTC based

date. This is done to prevent confusion when capturing areas within different time zones.

When downloading data from the USB or OBC it will come within a dated folder. This needs to

be pulled to a local directory of the users choosing. Each folder will contain various files that

are linked together through a lidarmeta file. It is important to keep all files within this folder as

missing files will cause a fault in processing.

Best practice is to download to USB thumb drive at the end of each flight, and copy that onto a

PC at the end of the day, and back up the data either to a cloud provider or separate physical

copy.

Aim to always have 3 copies of the raw data.

By default, data will be exported to an “Exports” subdirectory under the dataset.


9.1.4 Initial Interface

When opening the nextcore software the system will give you the option of four different

areas. This includes a live telemetry and data download used for the first generation of

Nextcore Units. A Process data set function, this is used within the RN50 model to process a

single flight. A Payload USB Control allows control of the internal payload storage via the USB

Thumb Drive.

9.2 Live Telemetry & Data Download This function is used for Nextcore generation 1 products only. To use this feature please refer

to the documentation provided with your Nextcore generation 1 product.

9.3 Batch Process Coming soon.


9.4 Process Dataset

9.4.1 Standard Data Processing Workflow

When choosing to process a single dataset you will be prompted to select the data that you

wish to process. Navigate to the directory within which your dataset is located and select the

appropriate lidarmeta file corresponding to the UTC time of the mission.


When the data is selected the mission will appear in a window similar to that shown above. This

is where the user can interact with the raw data and set postprocessing and fusion settings.

In the top right hand corner of the software the mission details will be presented. This includes

the date and time of the mission, the data path, payload ID and the mission duration. Also

present within this window will be an indicator if the dataset is post processed or not as well as

the availability of base data.

9.4.2 Post Processing It is necessary to post processes data against a base station. This will significantly improve data

accuracy and precision. This step within the Nextcore software performs a PPK solution on the

trajectory of the payload against a stationary base observer.

This is achieved through cloud processing and will require an internet connection cable of

uploading and downloading up to 300MB of data. This process uploads only the flight path,

IMU and selected base data to be processed to create an accurate lidar trajectory. Post

processing a flight will take up to 3 times the flight time however can be much shorter

depending on the nature of the flight path. Once a flight is post processed against a base

station it will be held in the cloud and will not need to be post processed again.

Lidar point data is not uploaded or stored in the cloud, it is kept locally on your computer to

protect your scan information - make sure you keep backups.


To post process a data set all you have to do is select a RINEX observation file from a base that

was within 10km of the flight and that covers the time period of the flight. Once the RINEX file

is selected, you will be notified if it is successfully applied.

At this point you may override the position of the base station, if it is known to be different to

that supplied in the RINEX header.

The position of the base station is taken from the RINEX header.

Once you are ready to post-process, click the “Post-Process” button, this will initiate the cloud

upload and processing - this will be presented in the status bar at the bottom of the software.

Once the dataset is post processed the base location will be displayed on the Map through a

green indicator. The dataset details will also change to outline that the dataset has been

post-processed.

If after the Post Processing step the position of the base station becomes known to greater

accuracy (ie the mark is surveyed or coordinates become available), you may select a Base

Location Override, using the “Set” option. You will need to re-export the data set for this to

apply.


The coordinates provided for Base Location Override should be in the same coordinate system

as specified for output in 9.5.5.3


9.4.3 Flight Line Selection The nextcore software can process either individual flight line or entire flight as desired by the

user. On the left side of the software interface the flight line selection is presented:

As seen above the mission path of the flight is automatically divided into individual flight lines.

This allows the user to only fuse together data that is necessary to the final deliverable saving

on processing time.

Each flight line is split into different colours and flight line ID’s. This flight line ID is also stored

in the point source id once the laz file has been exported. The automatic detection of flight

lines is controlled by the line split function. Depending on the flight - software may not

automatically detect the correct flight lines, the user can change the line split angle. This is the

minimum angular difference between one line and another. When doing linear scans this may

need to be lowered to account for small flight line direction changes.


Once the line split has been finalised and the user is happy with the different flight lines it is

important to uncheck all useless flight data. This includes any take off or landing delays as well

as short lines perpendicular to the desired grid mission. The user can either individually select

or deselect the flight lines they wish to use or they can apply an auto detect. This will guess the

desired flight lines based on the length, heading and spacing. When this guess flight line

function is used the user will be prompted with the number of flight lines found, the heading

and spacing. An example of this is seen below.

It is important to check that the undesired flightlines have been unchecked. This will present as

a black line on the map overlay. All coloured lines will be fused according to the fusion settings

chosen by the user.

9.4.4 Fusion Settings The fusion of data refers to the fusing of lidar point data to the flight path of the payload. This is

a very important step as it gives positioning to each individual point in the point cloud.


There are a various settings available for the fusing of data as seen above in the Fusion tab of

the Nextcore software, by default the settings are as per above. This will suit most data

captures, however, it is important to understand the settings and their implication for the

exports. These settings are split into the raw fusion settings as well as the optional decimation

step.


9.4.4.1 Fusion

Fusion Setting Description

Min Distance The minimum distance from the sensor to a point. Use to cut points on the drone, or potentially noise from birds / insects.

Max Distance The maximum distance from the sensor to a point. If flight lines are closer together, this may be worth changing down to decrease overlap.

Cut degrees The angle that is cut out of 360° sensor. This is taken from the center of the top of the lidar sensor. This is cut out to ignore the returns taken from the drone. This may need to be changed if the scanner is trying to capture horizontal data.

Deci distance The minimum distance between returns in-line with the laser scanner. This can ensure a more consistent point density and faster processing times. Set to zero to disable.

Deci angle The maximum angle that a laser return can be. This can be changed to avoid getting a returns off surfaces that are not very oblique. A side effect of this setting is that power lines and small features are sometimes missed. Set to zero to disable.

9.4.4.2 Combined Decimation:

Decimation of data is an additional step and will occur after the data is fused together. These

settings refer to the export of a decimated point cloud, which takes the best data from the

closest flight lines to get the most accurate point cloud. To enable this step the Combined Deci

function must be selected in the exports tab of the Nextcore software.

This is very useful as it can significantly reduce the size of point cloud whilst still retaining good

coverage and highest accuracy.

Min Dist This is the minimum distance between points within the dataset. Decreasing this increases density considerably. ~0.1m is ~100ppm2

~0.05m is ~400ppm2

Max Dist The maximum distance between data between flight lines, increasing this will allow more data from other flight lines. It is not recommended to change this setting.


Overlap This the distance that data from different flight lines can overlap. It is not recommended to change this setting.

Considerable RAM and CPU are required for this step, but it makes the resulting point clouds

much more consistent in density and easier to work with.

The Auto Calibrate Roll Offsets function is also available to the user. This will apply only if the

user is getting a decimated dataset. This function tries to automatically calculate any roll offset

between flight lines. This is recommended is the data set has a good ground surface, but flight

lines have visible roll errors.

Once run, flight lines with a calculated roll offset will have an asterisk shown next to them.

Pressing the clear roll offsets button will remove this, and it can be recalculated or left as

default.

The system uses a random sampling to calculate roll offsets, so results will vary between runs -

but are normally fairly consistent.

9.4.5 Export Settings This tab refers to the outputs desired from the software and their location path.

9.4.5.1 Export Paths

By default the desired data will be exported to an exports folder within the individual dataset

directory. This can be changed by copying the desired path into the text box. The user can also

select to export their data into a timed directory. This will put the desired exports into a


directory that is marked with that time step. This is useful to tick if the user is planning on

fusing the data multiple times and does not want the export to overwrite previous exports.

9.4.5.2 Export Options

This allows the User to specify export options. It is recommended to always only export

selected flight lines and compress the output to a Laz file.

The data can either be streamed to a single las/laz file or can be broken into individual flight

line las/laz files, even if a single file is export - the flight lines can be visualised from the point

source id field.

If the user requires a las file, then compress to LAZ can be unchecked. This will generate

uncompressed files, and should only be done for using software incompatible with laz files,

they are losslessly compressed - so no quality is lost for approximately 1/10th the file size.

9.4.5.3 Export Projections

This allows you to change the projections of the las/laz files to the prefered style and zone. This

will be matched by any base override coordinates.

9.4.5.4 Export Outputs

This is a check system for the files required in the exports folder. These are the deliverables of

the software. Checking Las File(s) will output a Las or Laz file depending on the export options

selected and the fusion setting chosen. Checking Map overlays output as per 9.5.5.6. Checking Combined Deci will output a decimated las/laz file in accordance to the decimation

setting chosen in the fusion tab, this takes more computational power that just streaming raw

data to a laz file.

9.4.5.5 Las / Laz file outputs

The main output are las or laz file outputs (laz are just losslessly compressed las files), version

1.4. The map projection as selected for export are included as WKT into the file.

The points fields are populated as follows:

PointSourceId - Flight line number of the return.

UserData - Stores the laser number (1-8) of the return.

ScanAngleRank - Distance in metres of the lidar return.

Intensity - The reflected signal strength of the lidar return.

Number of Returns, Return Number and GPS Time are populated as per specifications.

9.4.5.6 Map Overlays

If map overlays are selected in the exports setting once the data is exported the map overlays

option will be present to show data information over the current maps and flight path.


The overlays are as such:

Max Height - Colour ramp based on maximum height of lidar returns, shows tops of trees, tops

of objects.

Min Height - Colour ramp based on minimum height of lidar returns, generally ground surface

underneath canopy or objects.

Average Height - Averages based on the heights of lidar returns, rejects outliers.

Spread Height - The Max Height from the Min Height, generally shows canopy height for

vegetated areas.

Point Density - The density of LiDAR returns, which ramps from blue to red (red being >=

300ppm2)


9.5 Payload USB Control The USB drive can be used to interface with the RN50 system. This is a simple way to copy and

delete data off the payload in case of lost or deleted data. At the start of each power cycle of

the RN50 system a flight log is created on the USB drive (If present). This log can interface with

the Nextcore software in order to display all data sets present on the system. The RN50 has a

usable capacity of around 30GB and holds data in a FIFO (First In First Out) buffer

configuration. To access the available datasets on the RN50 system enter the USB payload

control function of the nextcore software.

Plug in the appropriate USB that contains the flight list. This will appear in the top drop down

drive list, select this USB drive. A number of processes can then be done including single file

and batch operations.


To copy or delete flight data for a single flight simply select that flight form the list and select

copy or remove. This can be done with multiple flights from the set.

There is also an option to dump or clear all data from the RN50 under the Batch Process tab.

This will affect all data on the payload.

Note: deleting or clearing data is permanent. Make sure this is the appropriate course of

action.


Once the appropriate commands are set up use the Write Commands button to send the

commands to the attached USB. This writes a text file that will initiate the commands when

next attached to the payload.

Attach the USB to the payload to execute the changes, ensure it is powered on. The command

file is removed from the USB at the end of each command sequence. While the payload is

executing the commands, it will display yellow flashing lights - wait for this to complete before

shutting down the payload.


10 Additional Attachments 10.1 RGB Camera

In order to create a colourised point cloud customers will need to obtain imagery of the area

using an RGB camera. The recommended methodology for this is to fly a separate mission

using a low cost, lightweight, UAV with in-built RGB camera. It is possible to hard mount a

camera to the bottom of the DJI M600 whilst the RN50 is attached by replacing the existing

rails with longer ones or by attaching a DJI Ronin Clamp Kit to the aerial of the RN50. Both of

these methods are not recommended by the manufacturer for the following reasons:

● These attachment methods add additional weight to the UAV and may reduce flight

time

● The mission profile will need to be altered to obtain the appropriate overlap for

creating the required mosaic for colourisation

● As the recommended flight height is 40 metres the number of photos required for a

consistent overlap, especially if trees are present is excessive and will have trouble

stitching.

In order to achieve a colourised point cloud, it is recommended to use an DJI Phantom 4 or

similar. Once the photos are taken, an Orthophoto may be generated and placed over the point

cloud to colourise the LiDAR returns.


11 Troubleshooting 11.1 Hardware OLED Errors This section outlines the different strings on the oled display including their meaning and

troubleshooting.

11.1.1 Line 1 The first line of the oled display will indicate the state of the system. The possible states of the

system are

- OK - System is booting

- Ready - System is ready to start capturing

- Lidar power down - Lidar sensor has been powered down, push button once to repower

lidar

- Capturing

11.1.2 Line 2 The second line of the oled display shows the state of the lidar sensor. The possible states of

the lidar are

- ERR Not connected

- Lidar has not bridged a connection yet, this will occur on boot. Give the sensor

up to 2 minutes to make a connection on boot. This will also occur when the

sensor is powered down. If the issue persists for longer than 2 minutes contact

your distributor.

- ERR No data yet

- Lidar has made a connection, the lidar sensor has to spin up to the appropriate

speed before data can be read, this will take ~30 seconds.

- ERR PPS Issue

- Internal mismatch between lidar sensor and GNSS timestamp. This may occur

on boot especially if the GNSS receiver has not made a fix yet. Give this 30

seconds to clear. If the issue persists contact your distributor.

- ERR Long Timesteps

- Internal mismatch between lidar sensor and GNSS timestamp. This may occur

on boot especially if the GNSS receiver has not made a fix yet. Give this 30

seconds to clear. If the issue persists contact your distributor.

- OK connected

- Lidar is networked into the payload and is ready for the capture to start.

- OK “######”

- This occurs when the lidar is capturing data, this will show the number of points

that the lidar sensor has captured.


11.1.3 Line 3 The third line of the oled display shows the state of the IMU/GNSS sensor. The possible states

of the GNSS sensor are

- ERR No signal

- This indicates the on board Imu/GNSS is not connected. Contact your

distributor if this occurs.

- ERR No Nav

- This indicates that the GNSS is not getting any signal from it’s antennas. This is

most likely caused by a faulty antenna connection. Recheck the connections at

the top of the RN50 system.

- ERR Init Heading

- This occurs when the antennas are properly attached to the system before it

has a GNSS fix. This will take up to 2 minutes. If this continues to occur, firstly

ensure the payload has a very clear sky view and both antennas are not

obstructed in any way. Secondly, make sure that there are no signal reflections

that could be occurring due to surfaces next to the system. If problems persist,

check connections to antennas at the top of the RN50 unit.

- Warn Acc Over Range

- This occurs when the onboard IMU is subjected to more the 2g of acceleration.

This can cause an error in data quality if the system is continually exposed to

high accelerations during data capture. This will not occur during a flight if the

mission planning guide and vibration isolators are used. This may however

occur on take off or landing of the system due to the increased acceleration of

the system. If this occurs on take off or landing the quality of the data will not be

affected.

- OK “GNSS” Fix

- This indicates that the system has a lock on a GNSS position and the system is

ready for data capture. Depending on location and time the system will lock on

to various constellations including GPS, GLONASS, SBAS. The sensor may also

present a 3D fix when using multiple constellation systems.

11.1.4 Line 4 The fourth line of the OLED display shows the internal state of the on board computer as well

as the API designated flight controller. The possible states are:

- STR ##.#GB free

- This indicates the amount of free storage space inside the payload - note this is

different to the USB thumb drive.


- FC No decode

- This indicates that the API auto capture cable is not connected or configured

correctly.

- FC Batt “##”%

- When the API auto capture is enabled and connected this will display the

battery percentage as reported by the A3 flight controller

- ERR No USB

- This shows that a USB storage device is not connected to the RN50 at the time

of stop capture. At the end of the capture if this error presents itself the user

can either insert a USB or they can choose to leave the data on the payload for

later retrieval. Not having a USB in the system at the end of a capture will not

result in the loss of that capture data, instead it will be stored on the payload for

later retrieval. You can insert USB after landing to initiate copy of the capture

to USB.

- BUSY USB Copy

- This will automatically happen at the end of each capture. This shows that data

is being copied from internal storage to the USB storage device.


11.2 Flight Operation FAQ When I power the UAV on the unit does not power on?

When the UAV is powered on the RN50 unit will power on with an oled logo and breathing

blue side lights. If this is not happening please check the connection between the UAV power

and RN50 unit.

When I power the UAV the payload gets power but the lights are staying red?

There are a number of system checks and initializations that the unit undergoes on boot. This

will present as red lights until they have been completed. If the system remains red for a long

period of time please check the oled display for a more detailed analysis of the issue. The oled

display will provide more information on what issue has occurred and how to resolve it. Please

refer to the operating payload section for more information.

I have flown a mission but the thumb drive was not installed prior to launch?

If you have landed your mission and notice that a USB drive is not attached to the payload you

can either plug one in before the end of the capture and proceed as normal. You can stop the

capture and keep the payload powered on whilst you find a USB, you can then plug in the USB

and the system will dump the previous flight to the USB. You can also refer to the Payload USB

Commands section of this guide to see how to extract data from the payload.

My base station was not powered on or not working during the flight?

To successfully post process flight data you will need to have RINEX observations for that

period. If your provided base has not produced rinex for that period it is recommended to

check for public GNSS observers that may be in the area. If these are not available you will not

be able to post process the flight.

What do I do if I crash or damage my RN50 payload?

If your unit is clearly damaged and/or inoperable you will need to contact your distributor to

arrange for an assessment of the damage and a quote on repairs. Even if the unit appears to be

in good working order it is important to understand that the equipment inside the NextCore

RN50 is very sensitive and the unit may require recalibration and testing.


11.3 Warranty Information

Your RN50 is given a 2-year parts and labour warranty, which is applied from the date of

purchase. This warranty does not include coverage for operations outside the manufacturer's

specifications, improper handling or misuse of the product or damage caused by crashing or

hard landing your UAV.

The unit is intended to be used in a DJI M600 Multirotor UAV, any use of the unit outside these

specifications without the express permission of the manufacturer will result in the warranty

being declared void.

For all warranty claims please contact your distributor for further advice.


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