SICK LRS4000 User manual

OPERATING INSTRUCTIONS
LRS4000
2D LiDAR sensors

Described product
LRS4000
Manufacturer
SICK AG
Erwin-Sick-Str. 1
79183 Waldkirch
Germany
Legal information
This work is protected by copyright. Any rights derived from the copyright shall be
reserved for SICK AG. Reproduction of this document or parts of this document is
only permissible within the limits of the legal determination of Copyright Law. Any modi‐
fication, abridgment or translation of this document is prohibited without the express
written permission of SICK AG.
The trademarks stated in this document are the property of their respective owner.
© SICK AG. All rights reserved.
Original document
This document is an original document of SICK AG.
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Contents
1 About this document........................................................................ 5
1.1 Information on the operating instructions.............................................. 5
1.2 Explanation of symbols............................................................................ 5
1.3 Further information................................................................................... 6
2 Safety information............................................................................ 7
2.1 Intended use............................................................................................. 7
2.2 Improper use............................................................................................. 7
2.3 Cybersecurity............................................................................................ 7
2.4 Limitation of liability................................................................................. 7
2.5 Modifications and conversions................................................................ 8
2.6 Requirements for skilled persons and operating personnel.................. 8
2.7 Operational safety and particular hazards.............................................. 8
3 Product description........................................................................... 10
3.1 Scope of delivery....................................................................................... 10
3.2 Status indicators....................................................................................... 10
3.3 Type label.................................................................................................. 10
3.4 Principle of operation............................................................................... 11
3.4.1 Measurement principle........................................................... 11
3.4.2 Range finding........................................................................... 12
3.4.3 Direction measurement.......................................................... 12
3.4.4 Impact of object surfaces on the measurement................... 12
3.4.5 Object sizes.............................................................................. 14
3.4.6 Multi-echo analysis.................................................................. 17
3.4.7 Filter.......................................................................................... 17
3.4.8 RSSI values.............................................................................. 19
3.4.9 Synchronization of the external clock and device clock........ 19
4 Transport and storage....................................................................... 21
4.1 Transport................................................................................................... 21
4.2 Unpacking.................................................................................................. 21
4.3 Transport inspection................................................................................. 21
4.4 Storage...................................................................................................... 21
5 Mounting............................................................................................. 23
5.1 Mounting instructions............................................................................... 23
5.2 Mounting device....................................................................................... 23
6 Electrical installation........................................................................ 24
6.1 Wiring instructions.................................................................................... 24
6.2 Prerequisites for safe operation of the device........................................ 25
6.3 Connection diagram................................................................................. 27
6.4 Connecting device electrically.................................................................. 29
6.5 Connecting encoder................................................................................. 29
CONTENTS
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7 Operation............................................................................................ 30
7.1 Operation using SOPASair........................................................................ 30
7.1.1 Opening user interface............................................................ 30
7.1.2 Overview................................................................................... 30
7.1.3 User levels................................................................................ 31
7.2 Operation in SOPAS ET............................................................................. 31
7.2.1 Installing and starting the configuration software................ 32
7.2.2 Logging into the device............................................................ 32
7.2.3 Output of measured values via terminal program................. 32
8 Maintenance...................................................................................... 35
8.1 Maintenance plan..................................................................................... 35
8.2 Cleaning..................................................................................................... 35
9 Troubleshooting................................................................................. 36
9.1 General faults, warnings, and errors....................................................... 36
9.2 Repairs...................................................................................................... 36
9.3 Returns...................................................................................................... 36
9.4 Disposal..................................................................................................... 36
10 Technical data.................................................................................... 37
10.1 Features.................................................................................................... 37
10.2 Mechanics/Electronics............................................................................. 38
10.3 Dimensional drawing................................................................................ 39
10.4 Performance............................................................................................. 40
10.5 Interfaces.................................................................................................. 40
10.6 Ambient data............................................................................................. 40
11 Accessories........................................................................................ 41
12 Annex.................................................................................................. 42
12.1 Declarations of conformity and certificates............................................ 42
12.2 Licenses.................................................................................................... 42
CONTENTS
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1 About this document
1.1 Information on the operating instructions
These operating instructions provide important information on how to use devices from
SICK AG.
Prerequisites for safe work are:
•Compliance with all safety notes and handling instructions supplied.
•Compliance with local work safety regulations and general safety regulations for
device applications
The operating instructions are intended to be used by qualified personnel and electrical
specialists.
NOTE
Read these operating instructions carefully to familiarize yourself with the device and its
functions before commencing any work.
The operating instructions are an integral part of the product. Store the instructions
in the immediate vicinity of the device so they remain accessible to staff at all times.
Should the device be passed on to a third party, these operating instructions should be
handed over with it.
These operating instructions do not provide information on operating the machine or
system in which the device is integrated. Information on this can be found in the
operating instructions for the machine or system.
1.2 Explanation of symbols
Warnings and important information in this document are labeled with symbols. Sig‐
nal words introduce the instructions and indicate the extent of the hazard. To avoid
accidents, damage, and personal injury, always comply with the instructions and act
carefully.
DANGER
… indicates a situation of imminent danger, which will lead to a fatality or serious
injuries if not prevented.
WARNING
… indicates a potentially dangerous situation, which may lead to a fatality or serious
injuries if not prevented.
CAUTION
… indicates a potentially dangerous situation, which may lead to minor/slight injuries if
not prevented.
NOTICE
… indicates a potentially harmful situation, which may lead to material damage if not
prevented.
NOTE
… highlights useful tips and recommendations as well as information for efficient and
trouble-free operation.
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1.3 Further information
NOTE
Further documentation for the device can be found on the online product page at:
•www.sick.com/LRS4000
There, additional information has been provided depending on the product, such as:
•Model-specific online data sheets for device types, containing technical data,
dimensional drawing, and specification diagrams
•Declarations of conformity and certificates of the product family
•Dimensional drawings and 3D CAD dimension models of the device types in
various electronic formats
•Other publications related to the devices described here
•Publications dealing with accessories
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2 Safety information
2.1 Intended use
The LRS4000 2D LiDAR sensor features 1 scan plane and is designed for the following
applications:
•Detection of objects during continuous output of measurement data as required.
•Detection and position determination of structures and objects.
It is suitable for applications which demand precise, non-contact optical measuring
contours and dimensioning. Typical applications include profile detection in container
handling, volume measurement in coal piles and boom protection on cranes.
2.2 Improper use
Any use outside of the stated areas, in particular use outside of the technical specifica‐
tions and the requirements for intended use, will be deemed to be incorrect use.
•The device does not constitute a safety component in accordance with the respec‐
tive applicable safety standards for machines.
•The device must not be used in explosion-hazardous areas, in corrosive environ‐
ments or under extreme environmental conditions.
•Any use of accessories not specifically approved by SICK AG is at your own risk.
WARNING
Danger due to improper use!
Any improper use can result in dangerous situations.
Therefore, observe the following information:
■Product should be used only in accordance with its intended use.
■All information in these operating instructions must be strictly observed.
■Shut down the product immediately in case of damage.
2.3 Cybersecurity
To protect against cybersecurity threats, it is necessary to continuously monitor and
maintain a comprehensive and holistic cybersecurity concept. A suitable concept com‐
prises organizational, technical, procedural, electronic, and physical levels of defense
and provides suitable measures for different types of risks. SICK's products and solu‐
tions must be viewed as a component of this concept.
Information on Cybersecurity can be found at: www.sick.com/psirt .
2.4 Limitation of liability
Relevant standards and regulations, the latest technological developments, and our
many years of knowledge and experience have all been taken into account when
compiling the data and information contained in these operating instructions. The
manufacturer accepts no liability for damage caused by:
■Non-adherence to the product documentation (e.g., operating instructions)
■Incorrect use
■Use of untrained staff
■Unauthorized conversions or repair
■Technical modifications
■Use of unauthorized spare parts, consumables, and accessories
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2.5 Modifications and conversions
NOTICE
Modifications and conversions to the device may result in unforeseeable dangers.
Interrupting or modifying the device or SICK software will invalidate any warranty claims
against SICK AG. This applies in particular to opening the housing, even as part of
mounting and electrical installation.
2.6 Requirements for skilled persons and operating personnel
WARNING
Risk of injury due to insufficient training.
Improper handling of the device may result in considerable personal injury and material
damage.
■All work must only ever be carried out by the stipulated persons.
The following qualifications are required for various activities:
Table 1: Activities and technical requirements
Activities Qualification
Mounting, maintenance ■Basic practical technical training
■Knowledge of the current safety regulations in the workplace
Electrical installation,
device replacement
■Practical electrical training
■Knowledge of current electrical safety regulations
■Knowledge of the operation and control of the devices in their
particular application
Commissioning, configura‐
tion
■Basic knowledge of the computer operating system used
■Basic knowledge of the design and setup of the described
connections and interfaces
■Basic knowledge of data transmission
Operation of the device for
the particular application
■Knowledge of the operation and control of the devices in their
particular application
■Knowledge of the software and hardware environment for the
particular application
2.7 Operational safety and particular hazards
Please observe the safety notes and the warnings listed here and in other sections
of this production documentation to reduce the possibility of risks to health and avoid
dangerous situations.
CAUTION
Optical radiation: Class 1 Laser Product
The accessible radiation does not pose a danger when viewed directly for up to 100
seconds. It may pose a danger to the eyes and skin in the event of incorrect use.
■Do not open the housing. Opening the housing may increase the level of risk.
■Current national regulations regarding laser protection must be observed.
Caution – Use of controls or adjustments or performance of procedures other than
those specified herein may result in hazardous radiation exposure.
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It is not possible to entirely rule out temporary disorienting optical effects, particularly
in conditions of dim lighting. Disorienting optical effects may come in the form of
dazzle, flash blindness, afterimages, photosensitive epilepsy, or impairment of color
vision, for example.
WARNING
Electrical voltage!
Electrical voltage can cause severe injury or death.
■Work on electrical systems must only be performed by qualified electricians.
■The power supply must be disconnected when attaching and detaching electrical
connections.
■The product must only be connected to a voltage supply as set out in the require‐
ments in the operating instructions.
■National and regional regulations must be complied with.
■Safety requirements relating to work on electrical systems must be complied with.
WARNING
Risk of injury and damage caused by potential equalization currents!
Improper grounding can lead to dangerous equipotential bonding currents, which may
in turn lead to dangerous voltages on metallic surfaces, such as the housing. Electrical
voltage can cause severe injury or death.
■Work on electrical systems must only be performed by qualified electricians.
■Follow the notes in the operating instructions.
■Install the grounding for the product and the system in accordance with national
and regional regulations.
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3 Product description
3.1 Scope of delivery
The delivery of the device includes the following components:
Table 2: Scope of delivery
No. of
units
Component Remarks
1 Device in the version ordered Depending on version
1 Set of protective caps for electri‐
cal connections
Attached to the connections
1 Printed safety notes, multilin‐
gual
Brief information and general safety notes
3.2 Status indicators
1 2
Figure 1: Status indicators
1APP LED
2DEV LED
APP LED (color) DEV LED (color) Description
O (Red) O (Red) Starting up
- – O (Red) Configuration
- – – Off
–O (Green) On / Ready for operation
- – Ö (Yellow) Warning
Ö Slow (red) Ö Slow (red) Error that can be corrected by the
customer
Ö Fast (red) Ö Fast (red) Fatal error
- – O (Yellow) Standby / Power save
Ö (Red)
Ö (Yellow)
Ö (Green)
Ö (Red)
Ö (Yellow)
Ö (Green)
Identification of the device
Ö (Red) Ö (Green) Firmware update
O = illuminated; Ö = flashing
3.3 Type label
The type label gives information for identification of the device.
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16
58à
á
ß
7
9
2
3
4
Figure 2: LRS4000 type label (example)
1Part number
2Type code
3Web address of product page
4Serial number
5Data Matrix code with product data and link to product page
6Manufacturer, place of production
7Production date
8Voltage supply, typical power, max. power, operating temperature, enclosure rating
9MAC address
ßNote: Do not remove type label
àConformity mark/certification mark, symbol: Observe the operating instructions!
áLabeling of connections
3.4 Principle of operation
3.4.1 Measurement principle
The device is an optoelectronic LiDAR sensor that contactlessly scans the outline of its
surroundings with the help of laser beams. The device measures its surroundings in
two-dimensional polar coordinates, relative to its measurement origin. This is marked
by a circular indentation in the center of the optics cover. If a laser beam strikes an
object, the position of that object is determined in terms of distance and angle.
Figure 3: LiDAR sensor with one scan plane
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3.4.2 Range finding
The device emits beams pulsed by a laser diode. If the laser beam is reflected by an
object, the reflected beam is received by the sensor.
The distance to the object is calculated on the basis of the time that the pulsed light
beam requires to be reflected and received by the sensor.
t
1 2
1Emitted pulse
2Receive pulse
3.4.3 Direction measurement
The laser beams are emitted using an internally rotating sender-receiver unit (SRUs)
and scan the surroundings orbitally. The received measured values are assigned to the
associated angular cut and thus to the direction.
3.4.4 Impact of object surfaces on the measurement
Remission value
Remission is the ability of a material to reflect light. The remission correlates with the
amount of laser light emitted by the LiDAR sensor which is reflected by an object (see
Lambert’s law).
Glossy surfaces have different remissions at the same distance with different angles of
impact. In the case of shiny surfaces, maximum remission is achieved when the beam
makes vertical impact.
Matt and dull surfaces have diffuse remission. They therefore exhibit similar relative
remissions with the same angle of impact regardless of the distance from the zero
point.
Table 3: Typical remissions of frequently used materials
Material Typ. relative remission
Rubber tires (vulcanized, black) 2%
Foam rubber (black) 2.4%
Photographic board (black, matte) 10%
Cardboard (gray) 20%
Wood (untreated fir, soiled) 40%
PVC (gray) 50%
Paper (white, matte) 80%
Plaster (white) 100%
Aluminum (black anodized) 110 … 150%
Steel (stainless, shiny) 120 … 150%
Steel (high gloss) 140 … 200%
Reflector > 1,000%
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The received signal from a perfectly diffuse reflection from a white surface (diffuse
Lambertian reflector) corresponds to a remission of 100%. By this definition, surfaces
that reflect the light in bundles (specular surfaces, reflectors) have remissions of over
100%.
Reflection
Most surfaces produce a diffuse reflection of the laser beam in all directions. The
structure (smooth or rough), shape (flat or curved), and color (light or dark) of the
surface determine how well the laser beam is reflected.
On very rough surfaces, a large proportion of the energy is lost due to absorption.
Curved surfaces produce a higher diffusion. Dark surfaces reflect the laser beam worse
than light ones (brilliant white plaster reflects approx. 100% of the light, while black
foam rubber reflects approx. 2.4%). The aforementioned surface characteristics can
reduce the scanning range of the device, in particular for surfaces with low remission
values.
Figure 4: Reflection of light on the surface of the object
Angle of reflection
The angle of reflection corresponds to the angle of incidence. If the laser beam hits
a surface at right angles, the energy is optimally reflected. If the laser beam hits a
surface at an oblique angle, energy and range are lost accordingly.
Figure 5: Angle of reflection
Retroreflection
If the reflective energy is greater than 100%, the beam is not reflected diffusely in all
directions; instead it is reflected in a targeted way (retroreflection). Thus a large part of
the emitted energy can be received by the laser distance measurer. Plastic reflectors
(cat’s eyes), reflective tape, and triple prisms have these properties.
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Figure 6: Retroreflection
Reflective surfaces
The laser beam is almost completely deflected on reflective surfaces. This means that
an object hit by the deflected beam may be detected instead of the reflective surface.
Figure 7: Specular surfaces
Small objects
Objects that are smaller than the diameter of the laser beam cannot reflect the laser
light’s full energy. The portion of the light beam that does not reach the object is lost. If
all of the light reflected to the sensor is insufficient, the object may not be detected.
The portion of the light that does not reach the front object can be reflected by a larger
object in the background. If all of the light reflected to the sensor is sufficient, this
object is detected. This can lead to a corruption of the measured value.
Figure 8: Object smaller than the laser beam diameter
3.4.5 Object sizes
As the distance from the device increases, the laser beam expands. As a result, the
diameter of the light spot on the surface of the object increases.
1
2
Figure 9: Beam expansion
1Expanded laser beam
2Optical axis
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Values required to calculate the light spot size:
•Light spot size on the device cover: 7 mm (rounded up)
•Divergence of single light spot: 0.023 deg (0.4 mrad) horizontally, 0.15 deg
(2.6 mrad) vertically
•Additional factor HDDM+ (The real spot size consists of several overlapping single
spots. The number of individual spots depends on the selected scan configuration)
Formula for calculating the light spot width:
(Light spot divergence horizontal [mrad] + HDDM+ supplement [mrad]) x distance [m] +
light spot size on the device cover [mm] = light spot width [mm]
Calculation example of light spot width at 30 m distance and 0.04° angular resolution:
(0.4 mrad + 0.698 mrad) * 30 m + 7 mm = 40 mm
Cannot be used for overlapping resolutions 0.020°/12.5 Hz and 0.040°/25 Hz. Spot
size here corresponds to 0.040°/12.5 Hz and 0.080°/25 Hz.
Formula for calculating the height of the light spot:
Light spot divergence [mrad] x distance [m] + light spot height at the device cover [mm]
= light spot height [mm]
Calculation example of spot height at 30 m distance: 2.6 mrad * 30 m + 7 mm =
85 mm
Formula for calculating the minimum object size (horizontal):
Angular resolution [mrad]) x distance [m] = minimum object size [mm]
Calculation example of minimum object size (horizontal) at 30 m distance and 0.04°
angular resolution: 0.7 mrad) * 30 m = 21 mm
Cannot be used for overlapping resolutions 0.020°/12.5 Hz and 0.040°/25 Hz. Mini‐
mum object sizes here correspond to 0.040°/12.5 Hz and 0.080°/25 Hz.
Formula for calculating the minimum object size (vertical):
(Light spot divergence vertical [mrad]) x distance [m] = minimum object size [mm]
Calculation example of minimum object size (vertical) at 30 m distance: 2.6 mrad *
30 m + 7 mm = 85 mm
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0.200° angular resolution
0.100° angular resolution
0.040° angular resolution
010
(32.81)
20
(65.62)
30
(98.43)
40
(131.23)
50
(164.04)
60
(196.85)
70
(229.66)
80
(262.47)
Beam diameter mm (in)
Target distance m (ft)
0
50
(1.97)
100
(3.94)
150
(5.91)
200
(7.87)
250
(9.84)
300
(11.81)
350
(13.78)
90
(295.27)
100
(328.08)
400
(15.75)
1
2
3
4
5
Figure 10: Minimum object size as a function of distance
1Minimum object size in mm (inch)
2Distance in m (ft)
3Minimum object size at angular resolution 0.040°
4Minimum object size at angular resolution 0.100°
5Minimum object size at angular resolution 0.200°
NOTE
Depending on the angular resolution selected, the number of single spots used varies.
For uninterrupted measurement of an object, it is important to hit the object with the
entire light spot width (all single spots). That means an object should be larger than the
minimum object size (continuous detection).
0.040° 0.040° 0.040°
1
2
1Single spots
2object size
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NOTE
In static applications, a target with the minimum object size may not be detected if the
entire light spot width (all single spots) does not hit the object. In moving applications
such as collision avoidance, the target would be measured alternately.
0.080° 0.080° 0.080°
1
2
1Single spots
2object size
3.4.6 Multi-echo analysis
The distance between the device and an object is calculated via the time-of-flight of the
emitted pulse. The device can evaluate up to three echo signals for each measuring
beam to deliver reliable measurement results, even under adverse ambient conditions.
Figure 11: Multi-echo analysis: example industrial application for ports, cranes, and traffic.
1Fog
2Rain
3Measuring object
3.4.7 Filter
By using digital filters to pre-process and optimize the measured distance values, the
device can be tailored to the specific requirements of the respective application. This
makes it possible to prevent virtually all faults.
The active filter functions affect the outputted measured values. It is not possible to
recalculate the original measured values from the filtered output values.
3.4.7.1 Echo filter
The echo filter screens out unwanted measurement data and signals caused by edge
hits, rain, dust, snow and other ambient conditions.
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You can set whether the first, the last, or all three echoes are output.
The other pulses triggered by undesirable ambient conditions are not taken into
account.
Echo 1
Echo 2
Figure 12: Without the echo filter: The device
receives unwanted echoes from ambient con‐
ditions such as rain.
Echo 1
Echo 2
Figure 13: Using the echo filter (setting: last
echo): the device screens out unwanted ech‐
oes from ambient conditions as per the set‐
tings chosen.
3.4.7.2 Median filter
This filter is suitable for excluding individual outliers from the calculation of an average
value.
The moving median filter sorts the measured values according to their size and selects
the middle value from this sequence. The values taken into consideration are defined
by a matrix, the size of which is configurable.
A 3 x 3 matrix, for example, takes into consideration 9 measured values consisting of
the distance values of a point and its two neighboring points, along with the distances
values of these points determined from the preceding and following scan. The fifth
largest measured value is outputted as the distance value.
Median calculation: 850 (lowest value) | 850 | 950 | 1,100 | 1150 (median) | 1,150
| 1,200 | 1,200 | 1,250 (highest value)
Table 4: Example: Median for scan 2 and angle 3 (3 x 3 matrix: scan 1 to 3, angle 2 to 4)
Angle (distance values)
Scan 1 2 3 4 5 …
100 850 1100 1150 …
200 950 1200 1250 …
300 850 1150 1200 …
…… … … … … …
Median calculation: 0 (lowest value) | 0 | 0 | 850 | 850 (median) | 950 | 1,100 |
1,150 | 1,200 (highest value)
Table 5: Example: Median for scan 2 and angle 4 (3 x 3 matrix: scan 1 to 3, angle 3 to 5)
Angle (distance values)
Scan 1 2 3 4 5 …
10 0 850 1100 1150 …
20 0 950 1200 1250 …
30 0 850 1150 1200 …
…… … … … … …
Median calculation: 850 (lowest value) | 850 | 950 | 1,100 | 1150 (median) | 1,150
| 1,200 | 1,200 | 1,250 (highest value)
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3.4.7.3 Average filter
Using the mean filter, a blockwise (not moving) arithmetic average is calculated from
the configured number of scans and then outputted. The big advantage when using this
filter: Potential noise, i.e. minimal deviation of values, is reduced, which also lowers the
quantity of data.
15 m
17 m
Figure 14: Without the mean filter: The device
detects and processes all received signal val‐
ues.
Ø 16 m
Figure 15: Using the mean filter: The device
calculates an average value from several sig‐
nal values.
3.4.8 RSSI values
RSSI (Received Signal Strength Indicator) is the measure of the signal strength that the
device receives. This value is calculated for every measurement. The device therefore
provides, for every echo signal, an associated RSSI value for the signal strength.
The resolution of the RSSI data output can be switched between 8 bit and 16 bit.
•8 bits: The RSSI values have a resolution of 8 bits with whole-number values
between 1 and 255, where 1 represents the weakest signal and 254 the strongest
signal (e.g., with a reflector). A value of 255 means "blinded".
•16 bits: The RSSI values have a resolution of 16 bits with whole-number values
between 1 and 65,535, where 1 stands for the weakest signal and 65,534 for the
strongest signal (e.g. with one reflector). A value of 65,535 means “dazzled”.
The value 0 (zero) means that the received energy was too low to produce a valid
measured value. A valid distance measurement has at least an RSSI value of 1.
If the RSSI value is 0, then no distance measurement is possible. There can be two
reasons for this:
•The target object lies outside the sensing range.
•The target object has an extremely low remission.
Please note that white paper can have very similar values as a reflector at a short
distance.
The RSSI values are sensor-specific, relative values that can vary slightly between
different devices and during the service life of the device.
3.4.9 Synchronization of the external clock and device clock
For precise control, the contour data of the device and the calculations in the external
computer must be synchronized as accurately as possible in time.
The measurement data from the device is provided with the internal time stamp. The
internal time stamp in the device is a 32-bit counter which increases in increments of 1
every 1 ms.
The scan data output starts at -180°.
PRODUCT DESCRIPTION 3
8026338/0000/2022-02-15 | SICK O P E R A T I N G I N S T R U C T I O N S | LRS4000 19
Subject to change without notice

There are two ways to synchronize the internal time of the device with the system time
of the controller:
•Via telegram: The computer queries the internal time of the device using a tele‐
gram. The device writes its internal time in a telegram and sends this to the
computer. Sending can happen with a delay time of up to a few milliseconds,
which results in some uncertainty.
•Via index (pulse at hardware output): The device outputs a signal depending on
the sender/receiver position. This signal is used, for example, to synchronize scans
with the position of a swivel device for 3D measurement.
3 PRODUCT DESCRIPTION
20 O P E R A T I N G I N S T R U C T I O N S | LRS4000 8026338/0000/2022-02-15 | SICK
Subject to change without notice