Dual Wavelength Waveform Processing Airborne LiDAR Scanning System for High-Point Density Mapping Applications

Transcription

1 Dual Wavelength Waveform Processing Airborne LiDAR Scanning System for High-Point Density Mapping Applications NEW RIEGL VQ-156i-DW enhanced target characterization based upon simultaneous measurements at green and infrared laser wavelengths high laser pulse repetition rate of up to 1 MHz per laser channel The VQ-156i-DW is a new airborne LiDAR scanning system offering two LiDAR channels of different wavelengths, green and infrared (IR). These wavelengths are well chosen to allow the acquisition of scan data of complementary information content, thus delivering two independent reflectance distribution maps, one per laser wavelength. up to 1.33 million measurements per Scan data acquired with the RIEGL VQ-156i-DW are the input for wellestablished scan data processing methods but also for the develop- second on the ground ment of highly sophisticated data a processing and evaluation algorithms data acquisition at a wide range of for new areas of application like vegetation mapping in agriculture and point densities forestry. Thus the VQ-156i-DW -DW offers innovative technology for commercial as well as scientific and research applications. The VQ-156i-DW provides a laser pulse repetition rate of up to excellent multiple target capability enables Multiple-Time-Around (MTA) processing of up to 2 pulses 1MHz per LiDAR channel, resulting in a total of more than 1.3 million simultaneously in the air measurements per second on the ground. The VQ-156i-DW works at highest productivity when both LiDAR online waveform processing as channels are combined, typically at altitudes up to 83 ft. However, well as smart and full waveform each channel is also prepared for stand-alone operation. This channel recording for both LiDAR channels selection capability in combination with a matched line of measu- integrated inertial measurement rement programs as well as widely variable scan parameters enable unit and GNSS receiver highest possible flexibility for meeting highly specific requirements of integrated, easily accessible challenging application scenarios. medium format camera The system is completed by a high performance IMU/GNSS unit and up two optional cameras. A 1 megapixel RBG camera is intended to prepared for integration of a be used as primary camera, as secondary camera a thermal or a NIR secondary camera camera can be built in. The mounting flange is optimized for simple high-speed fiber data interface to ELto interfacing with typical aircraft hatches and stabilized mounts by means RIEGL data recorder r of a specific adapter ring. housing shape and mounting ng flange optimized for interfacing ing with typical hatches hes and stabilized iz platforms ELIMINARY Applications: Scientific and Research Applications Agriculture and Forestry Mapping of Vegetation and Normalized Difference Vegetation Index (NDVI) Glacier & Snowfield Mapping Mapping of Lake Sides & River Banks High Point Density Mapping Corridor Mapping visit our website Airborne Laser Scanning

2 RIEGL VQ-156i-DW Scan Pattern effective FOV 28 RIEGL VQ-156i-DW Elements of Function and Operation aperture of primary camera (RGB) Each channel nel delivers straight parallel scan lines. The scan lines of the two channels are tilted against each other by 28 degrees providing an optimum distribution ion of the measurements on the ground invariant to changes in terrain height. Tilt Angle of Scan Lines ± 14 Forward/Backward Scan Angle in Non-Nadir Direction ± 8 at the edge PRELIM IMI MINAR ARY mounting flange aperture of IR laser channel IMU bay aperture of green laser channel aperture of secondary camera connectors for power supply and data interface desiccant cartridges cooling air outlets carrying handles 2 Copyright RIEGL Laser Measurement Systems GmbH 217 All rights reserved.

3 RIEGL VQ-156i-DW Main Dimensions all dimensions in mm Copyright RIEGL Laser Measurement Systems GmbH 217 All rights reserved. 3

4 RIEGL VQ-156i-DW System Components GNSS antenna USB 3. interface high speed interface LAN interface - flight guidance LAN interface - system control laser safety switch RIEGL VQ-156i-DW gyro-stabilized mount GSM-4 (optional) control for gyro-stabilized mount laser safety switch RIEGL VQ-156i-DW Installation Examples operator working station (optional) pilot tdis display flight guidance (optional) RIEGL DR156 FOTO ix- Controller (optional) A minimum number of system components and external cabling is required for an easy and quick installation in aircrafts. PRE RELIMINARY RIEGL VQ-156i-DW installed in the nose pod of fixed-wing aircraft DA42 MPP RIEGL VQ-156i-DW installed on GSM-4 gyro-stabilized platform preferably to be used with fixed-wing aircrafts 4 Copyright RIEGL Laser Measurement Systems GmbH 217 All rights reserved.

5 Measurement Range & Point Density - Green and IR Laser Channel PRR = 2x7 khz, laser power level 1%, green and IR laser channel visibility 4 km Target Example: VQ-156i-DW at 2 x 7, pulses/sec, laser power level 1% Altitude = 3,7 ft AGL, Speed = 115 kn Example: VQ-156i-DW at 2 x 1,, pulses/sec, laser power level 1% Altitude = 5,6 ft AGL, Speed = 17 kn ft 49 ft 65 ft 86 ft 28 ft (85 m) 37 ft (113 m) 45 ft (15 m) 65 ft (198 m) 86 ft (262 m) 28 ft 96 m 126 m 167 m 222 m 294 m Results: Point Density ~ 12.5 pts/m² Area Acquisition Rate ~ 215 km²/h d IR laser ch Flight Altitude AGLR AGL Swath Width 27 ft (82 m) 92 m 35 ft (117 m) 12 m 44 ft (134 m) 15 m 56 ft (171 m) 191 m 72 ft (219 m) 246 m PRR = 2x1 khz, laser power level 1%, green and IR laser channel visibility 4 km L Example: VQ-156i-DW at 2 x 1,, pulses/sec, laser power level 5% Altitude = 4,1 ft AGL, Speed = 15 kn M ft 44 ft 56 ft 72 ft 27 ft Results: Point Density ~ 8 pts/m² Area Acquisition Rate ~ 48 km²/h PRR = 2x1 khz, laser power level 5%, green and IR laser channel visibility 4 km Target The following conditions are assumed for the Operating Flight Altitude AGL ambiguity resolved by multiple-time-around (MTA) processing target size laser footprint average ambient brightness effective FOV roll angle ±5 PRE RE ELI LIM IM3MINAR MINA ARY ft 32 ft 41 ft 53 ft 19 ft (58 m) 25 ft (76 m) 32 ft (98 m) 41 ft (125 m) 53 ft (162 m) 19 ft 65 m 85 m 19 m 14 m 181 m Results: Point Density ~ 12.3 pts/m² Area Acquisition Rate ~ 31 km²/h Assumptions for calculation of the Area Acquisition Rate 2% overlap of neighboring flight strips. This overlap covers a roll angle of ±5 or a reduction of flight altitude AGL of 2%. Typical ENOHD Calculated under assumption of an angular step width of.12, a beam divergence of.72mrad of the green laser and an aircraft speed higher than 5kn Copyright RIEGL Laser Measurement Systems GmbH 217 All rights reserved. 5

6 Measurement Range & Point Density - Green and IR Laser Channel PRR = 2x1 khz, laser power level 25%, green and IR laser channel visibility 4 km Target Example: VQ-156i-DW at 2 x 1,, pulses/sec, laser power level 25% Altitude = 3, ft AGL, Speed = 125 kn Example: VQ-156i-DW at 2 x 1,, pulses/sec, laser power level 12% Altitude = 1,2 ft AGL, Speed = 15 kn ft 3 ft 4 ft 17 ft 13 ft (4 m) 17 ft (52 m) 23 ft (7 m) 3 ft (91 m) 4 ft (122 m) 13 ft 44 m 58 m 79 m 12 m 137 m Results: Point Density ~ 2.2 pts/m² Area Acquisition Rate ~ 19 km²/h PRR = 2x1 khz, laser power level 12%, green en and IR laser channel visibility 4 km Target 1 8 M M N ft 16 ft 21 ft 28 ft 12 ft 9 ft (27 m) 12 ft (37 m) 16 ft (49 m) 21 ft (64 m) 28 ft (85 m) 31 m 41 m 55 m 72 m 96 m PRELIMI MIN MINARY NAR NARFl Results: Point Density ~ 6.2 pts/m² Area Acquisition Rate ~ 64 km²/h The following conditions are assumed for the Operating Flight Altitude AGL ambiguity resolved by multiple-time-around (MTA) processing target size laser footprint average ambient brightness effective FOV roll angle ±5 Assumptions for calculation of the Area Acquisition Rate 2% overlap of neighboring flight strips. This overlap covers a roll angle of ±5 or a reduction of flight altitude AGL of 2%. Typical ENOHD Calculated under assumption of an angular step width of.12, a beam divergence of.72mrad of the green laser and an aircraft speed higher than 5kn. Copyright RIEGL Laser Measurement Systems GmbH 217 All rights reserved. 6

7 Measurement Range & Point Density - IR Laser Channel Only PRR = 15 khz, laser power level 1%, IR channel only visibility 4 km ft (177 m) 198 m 74 ft (226 m) 253 m 93 ft (283 m) 318 m 118 ft (36 m) 43 m 15 ft (457 m) 512 m PRR = 25 khz, laser power level 1%, IR channel only visibility 4 km Target Example: VQ-156i-DW at 25, pulses/sec, laser power level 1% Altitude = 12,9 ft AGL, Speed = 145 kn PRR = 35 khz, laser power level 1%, IR channel only Example: VQ-156i-DW at 15, pulses/sec, laser power level 1% Altitude = 15, ft AGL, Speed = 15 kn visibility 4 km Target E NAR M ft 99 ft 129 ft Results: Point Density ~.25 pts/m² Area SR Acquisition Rate ~ 113 km²/h 58 ft 44 ft (134 m) 15 m 58 ft (177 m) 198 m 75 ft (229 m) 256 m 99 ft (32 m) 338 m 129 ft (393 m) 441 m 44 ft ft 85 ft 112 ft 74 ft 93 ft 118 ft 15 ft 5 ft 58 ft Results: Point Density ~.5 pts/m² Area Acquisition Rate ~ 95 km²/h 38 ft (116 m) 13 m 5 ft (152 m) 171 m 65 ft (198 m) 222 m 85 ft (259 m) 29 m 112 ft (341 m) 382 m 38 ft PRE RELI LIM MINAR 2MINA ARY Example: VQ-156i-DW at 35, pulses/sec, laser power level 1% Altitude = 8,5 ft AGL, Speed = 155 kn The following conditions are assumed for the Operating Flight Altitude AGL ambiguity resolved by multiple-time-around (MTA) processing target size laser footprint average ambient brightness effective FOV roll angle ±5 Typical ENOHD Calculated under assumption of an angular step width of.12 and an aircraft speed higher than 5kn. Results: Point Density ~ 1 pts/m² Area Acquisition Rate ~ 67 km²/h Assumptions for calculation of the Area Acquisition Rate 2% overlap of neighboring flight strips. This overlap covers a roll angle of ±5 or a reduction of flight altitude AGL of 2%. Copyright RIEGL Laser Measurement Systems GmbH 217 All rights reserved. 7

8 Measurement Range & Point Density - IR Laser Channel Only PRR = 5 khz, laser power level 1%, IR channel only visibility 4 km Target Example: VQ-156i-DW at 5, pulses/sec, laser power level 1% Altitude = 5,5 ft AGL, Speed = 17 kn The following conditions are assumed for the Operating Flight Altitude AGL ambiguity resolved by multiple-time-around (MTA) processing target size laser footprint average ambient brightness effective FOV roll angle ±5 Typical ENOHD Calculated under assumption of an angular step width of.12 and an aircraft speed higher than 5kn. RIEGL VQ-156i-DW Productivity The RIEGL VQ-156i-DW offers highest flexibility due to its channel selection capability. Area Acquisition Rate [km²/h] Average Point Density [pts/m²] ft 55 ft 72 ft 96 ft 31 ft (94 m) 41 ft (125 m) 55 ft (168 m) 72 ft (219 m) 96 ft (293 m) 31 ft 16 m 14 m 188 m 246 m 328 m Results: Point Density ~ 2 pts/m² Area Acquisition Rate ~ 47 km²/h Assumptions for calculation of the Area Acquisition Rate 2% overlap of neighboring flight strips. This overlap covers a roll angle of ±5 or a reduction of flight altitude AGL of 2%. Productivity of the VQ-156i-DW when using both channels and a typical fixed-wing aircraft with an airspeed >15kn Using an aircraft with a high maximum speed, e.g. up to 27 kn, allows an increase of the VQ-156i-DW s productivity at low point densities. Very high point densities can be achieved when using the VQ-156i-DW with a helicopter Productivity of a single LiDAR channel of the VQ-156i-DW At very low point densities the maximum area acquisition rate can be achieved when using the infrared LiDAR channel only. PRELIMI MINAR NARYRY Examples 1) Average Point Density 2 pts/m 2 8 pts/m 2 2 pts/m 2 6 pts/m 2 Flight Altitude 5 ft 45 ft 33 ft 115 ft 152 m 137 m 1 m 351 m Ground Speed 27 kn 21 kn 115 kn 11 kn Swath Width 17 m 154 m 113 m 4 m Productivity 67 km 2 /h 48 km 2 /h 192 km 2 /h 64 km 2 /h Measurement Rate 2) 466 meas./sec 2 x 666 meas./sec 2 x 666 meas./sec 2 x 666 meas./sec Channel Selection infrared only green & infrared green & infrared green & infrared Camera GSD 3) 4) 14 mm 126 mm 92 mm 32 mm Camera Trigger Intervall 4) 3.5 sec 4.1 sec 5.4 sec 2. sec 1) calculated for 2% target reflectivity and 2% stripe overlap 2) The target detection rate is equal to the measurement rate for terrains offering only one target per laser pulse but may be much higher for vegetated areas. 3) Ground Sampling Distance 4) Calculated for a 1 MPixel CMOS camera with a FOV of 56.2 x 43.7 and 6% image overlap in flight direction (endlap). 8 Copyright RIEGL Laser Measurement Systems GmbH 217 All rights reserved.

9 Technical Data RIEGL VQ-156i-DW Export Classification The VQ-156i-DW is subject to export restrictions as set up by the Wassenaar Arrangement. Although the Dual-Wavelength LiDAR Scanning System VQ-156i-DW It is classified as dual-use good according to position number 6A8j3 of the official Dual-Use-List has not been designed and developed for bathymetric surveys, it offers to be found on site due to integrating a green laser to a limited extent the capability for Within the European Union, Council Regulation (EC) No 428/29 implements the export hydrographic surveys. restrictions of the Wassenaar Arrangement. The corresponding position number is 6A8j3. Laser Product Classification Class 3B Laser Product according to IEC :214 Range Measurement Performance The instrument must be used only in combination with the appropriate laser safety box. as a function of laser power setting, PRR, and target reflectance Laser Power Level: Green and IR Laser Channel 1% 1% 5% 25% 12% Laser Pulse Repetition Rate (PRR) 1) 2 x 7 khz 2 x 1 khz 2 x 1 khz 2 x 1 khz 2 x 1 khz 2) 3) Max. Measuring Range natural targets, min. 2 % reflectance 2 m 17 m 13 m 94 m 68 m natural targets, min. 6 % reflectance 31 m 27 m 2 m 15 m 112 m Max. Operating Flight Altitude 25 m 22 m 16 m 12 m 91 m Above Ground Level (AGL) 2) 4) 83 ft 725 ft 53 ft 4 ft 3 ft mrad of the green laser 5) 7) 28 m 24 m 165 m 115 m 8 m mrad of the green laser 6) 7) 112 m 94 m 65 m 45 m 32 m 1) rounded average PRR 2) Typical values for average conditions and average ambient brightness; in bright sunlight the operational range may be considerably shorter and the operational flight altitude may be considerably lower than under an overcast sky. 3) The maximum range is specified for flat targets with size in excess of the laser beam diameter, perpendicular angle of incidence, and for atmospheric visibility of 4 km. Range ambiguities have to be resolved by multiple-time-around processing. 4) Typical values for 6 % reflectance, max. effective FOV, additional roll angle ± 5 5) Nominal Ocular Hazard Distance, based upon MPE according to IEC :214, for single line condition 6) Extended Nominal Ocular Hazard Distance, based upon MPE according to IEC :214, for single line condition 7) NOHD and ENOHD have been calculated for a typical angular step width of.12, an aircraft speed higher than 5kn, and beam divergences of.72 mrad for the green laser and.25 mrad for the IR laser. NOHD and ENOHD increase when reducing the angular step width or the green laser s beam divergence. Laser Power Level: IR Laser Channel only 1% Laser Pulse Repetition Rate (PRR) 1) 15 khz 25 khz 35 khz 5 khz 2) 3) Max. Measuring Range natural targets, min. 2 % reflectance 38 m 31 m 27 m 23 m natural targets, min. 6 % reflectance 58 m 48 m 42 m 36 m Max. Operating Flight Altitude 47 m 39 m 34 m 29 m Above Ground Level (AGL) 2) 4) 155 ft 129 ft 112 ft 96 ft NOHD 5) 7) 37 m 29 m 24 m 2 m ENOHD 6) 7) 245 m 19 m 16 m 135 m 1) rounded average PRR 2) Typical values for average conditions and average ambient brightness; in bright sunlight the operational range may be considerably shorter and the operational flight altitude may be considerably lower than under an overcast sky. 3) The maximum range is specified for flat targets with size in excess of the laser beam diameter, perpendicular angle of incidence, and for atmospheric visibility of 4 km. Range ambiguities have to be resolved by multiple-time-around processing. 4) Typical values for 6 % reflectance, max. effective FOV, additional roll angle ± 5 5) Nominal Ocular Hazard Distance, based upon MPE according to IEC :214, for single line condition 6) Extended Nominal Ocular Hazard Distance, based upon MPE according to IEC :214, for single line condition 7) NOHD and ENOHD have been calculated for a typical angular step width of.12 which means non-overlapping laser footprints and an aircraft speed higher than 5kn. NOHD and ENOHD increase when using overlapping laser footprints which may be intended e.g. for power line mapping. Minimum Range 8) 1 m 9) 1) Accuracy 2 mm 1) 11) Precision 2 mm Laser Pulse Repetition Rate up to 2 x 1 khz Effective Measurement Rate up to 2 x scan angle Echo Signal Intensity provided for each echo signal Laser Wavelength green (532 nm) and near infrared (164 nm) Laser Beam Divergence user selectable for the green laser: approx..7 mrad to approx. 2 mrad (1/e²) 12) fixed for the IR laser:.18 mrad (1/e) 13),.25 mrad (1/e²) 14) Number of Targets per Pulse 15) 16) with online waveform processing: practically unlimited monitoring data output: first pulse 8) Limitation for range measurement capability, does not consider laser safety issues! The minimum range for valid reflectance values is 25 m. 9) Accuracy is the degree of conformity of a measured quantity to its actual (true) value. 1) Standard deviation one 25 m range under RIEGL test conditions. PRELIM MINARY RY 11) Precision, also called reproducibility or repeatability, is the degree to which further measurements show the same result. 12) A license for lower divergence settings is available on request based on a signed liability disclaimer. 13).18 mrad corresponds to an increase of the 1/e beam diameter of 18 cm per 1 m distance. 14).25 mrad corresponds to an increase of the 1/e² beam diameter of 25 cm per 1 m distance. 15) Depending on laser pulse repetition rate, up to a max. of 15 targets per laser pulse. 16) If the laser beam hits, in part, more than one target, the laser s pulse power is split accordingly. Thus, the achievable range is reduced. Technical Data to be continued at page 1 Copyright RIEGL Laser Measurement Systems GmbH 217 All rights reserved. 9

10 Technical Data RIEGL VQ-156i-DW (continued) Scanner Performance Scanning Mechanism rotating polygon mirror Scan Pattern parallel scan lines per channel, crossed scan lines between channels Tilt Angle of Scan Lines ± 14 = 28 Forward/ Backward Scan Angle in Non-Nadir Direction ± 8 at the edges Scan Angle Range 6 total per channel, resulting in an effective FOV of Total Scan Rate 4 1) - 6 lines/sec Angular Step Width 2) 3).12 Angle Measurement Resolution.1 1) The minimum scan rate depends on the selected laser PRR. 2) The minimum angular step width depends on the selected laser PRR. Data Interfaces Configuration Monitoring Data Output Digitized Data Output Synchronization General Technical Data Power Supply / Power Consumption Main Dimensions (flange diameter x height) Weight Protection Class Max. Flight Altitude operating / not operating Temperature Range operation / storage 4) Mean Sea Level Recommended IMU/GNSS System 5) 6) 3) The maximum angular step width is limited by the maximum scan rate. TCP/IP Ethernet (1/1/1 MBit/s) TCP/IP Ethernet (1/1/1 MBit/s) Dual glass fiber data link to RIEGL Data Recorder DR156 Serial RS232 interface, TTL input for 1 pps synchronization pulse, accepts different data formats for GNSS-time information 2-32 V DC / typ. 25 W max. 55 W, depending on integrated ted optional components Ø 524 mm x 78 mm m (without flange mounted carrying handles) approx. 6 kg without any camera but including a typical IMU/GNSS unit approx. 7 kg with optional components IP ft (56 m) above MSL 4) / 185 ft (56 m) above MSL C up to +4 C / -1 C up to +5 C IMU Accuracy 7) Roll, Pitch.25 Heading.5 IMU Sampling Rate 2 Hz Position Accuracy (typ.).5 m -.3 m Optional Components VQ-156i-DW Primary Camera ELIM.2 RGB Sensor Resolution up to 1 MPixel CMOS without FMC or up to 8 MPixel CCD with FMC Sensor Dimensions s (diagonal) 67.2 mm (medium format) Focal Length of Camera Lens 5 mm Field of View (FOV) approx x 43.7 Interface USB 3. Data Storage ix-controller PRE IMINARY Secondary Camera 5) The recommended IMU is listed neither in the European Export Control List (i.e. Annex 1 of Council Regulation 428/29) nor in the Canadian Export Control List. Detailed information on certain cases will be provided on request. 6) The RIEGL VQ-156i-DW Laser Scanning system supports different IMU/GNSS Systems, details on request. Different camera types including thermal or NIR cameras can be integrated, details on request. 7) One sigma values, no GNSS outages, post-processed with base station data RIEGL Laser Measurement Systems GmbH Riedenburgstraße Horn, Austria Phone: Fax: office@riegl.co.at Copyright RIEGL Laser Measurement Systems GmbH 217 All rights reserved. Use of this data sheet other than for personal purposes requires RIEGL s written consent. This data sheet is compiled with care. However, errors cannot be fully excluded and alternations might be necessary. RIEGL USA Inc. Orlando, Florida info@rieglusa.com RIEGL Japan Ltd. Tokyo, Japan info@riegl-japan.co.jp RIEGL China Ltd. Beijing, China info@riegl.cn RIEGL VQ-156i-DW,