articulated pedestrian target … · crossing pedestrian whereas arm movement seems to be...

ARTICULATED

PEDESTRIAN TARGET

SPECIFICATIONS

Articulated Pedestrian Target Specifications

Version 1.0

Articulated Pedestrian Target Specifications – Version 1.0 1

Document history

Version Modified by Date Description / Modification

0.1 Thomas Wimmer (4a)

Martin Fritz (4a)

10.3.2015 Draft Specifications

0.2 ACEA-Group (SG Art. Dummy)

Martin Fritz (4a)

11.3.2015 Input from Spec- Workshop in Sindelfingen

0.2.2 Frank Baumann 25.3.2015 Consideration of Feedback of SG Dummy

0.3 Frank Baumann 26.5.2015 Consideration of Feedback of SG Dummy and Testing at VENLO

0.3.2 Frank Baumann 29.5.2015 Consideration of Feedback of SG Dummy members

0.3.3 Frank Baumann 02.07.2015 Consideration of Feedback of Radar Expert Telco 02.07.

0.3.4 ACEA-Group (SG Art. Dummy)

Martin Fritz (4a)

10.08.2015 Workshop - Sindelfingen

0.4.0 Thomas Wimmer (4a)

Martin Fritz (4a)

01.09.2015 Including movement data’s for ankle and knee, RCS-boundaries from Bosch and Conti

0.5.0 Frank Baumann 07.09.2015 Editorial changes, RCS measurements added to Annex

0.6.0 Frank Baumann 11.09.2015 Statistical evaluation of RCS of real pedestrians by Bosch added to Annex

1.0 Thomas Wimmer (4a)

Martin Fritz (4a)

21.10.2015 Speed characteristic of ankle and knee

Changing Arm posture to harmonize with static Dummy


ARTICULATED PEDESTRIAN TARGET

CONTENT

1 Introduction 3

1.1 General Information 3

1.2 Definitions 3

2 Pedestrian Target 3

2.1 Pedestrian Target Dimensions 3

2.2 Visible and Infrared Properties 6

2.3 Radar Properties 7

2.3.1 Radar Cross Section (RCS) 7

2.3.2 Doppler Effect of Articulation 8

2.4 Articulation 9

2.5 Mounting and Guidance System 12

2.6 Pedestrian Target Weight and Collision Stability 12

Appendix 14

A1 Measurement of the IR reflectivity 14

A2 Measurement of Radar Reflectivity 16

A3 Example Measurements of RCS 19

A4 Example Measurements of Micro Doppler 21


1 INTRODUCTION

1.1 GENERAL INFORMATION

Based on the vFSS-protocol (V1.1 from 27.10.2014) for the static dummy and the outcome of the

ACEA-Project Articulating Dummy as well as the pre-studies from 4activeSystems the following

specification defines an articulated pedestrian target. The articulation adds additional

characteristics of a moving pedestrian and therefore is providing an improved image of a human

pedestrian compared to a non-articulated dummy. The actual protocol only the crossing sceneries

are validated. An update for longitudinal sceneries is planned on a later stage.

1.2 DEFINITIONS VUT Vehicle under test PT Pedestrian target

2 PEDESTRIAN TARGET

The PT must be able to represent the human attributes in relation to the sensors used in the vehicle.

The required sensor-relevant PT attributes for a system test are determined by the vehicle

manufacturer and have to be implemented in the manner specified in this document. The

requirements relate, insofar not specified otherwise, to the PT including a guiding rod. The PT has

to be detectable by following automotive sensors technologies: RADAR, Video, Laser, PMD, IR-

based system. The PT consists of two articulated legs, two static arms, torso and an interface-

center-tube either from lower side (platform) or from upper side (test rig).

2.1 PEDESTRIAN TARGET DIMENSIONS

The shape of the adult PT refers to the contours with the 50 % RAMSIS Bodybuilder (Child PT -

RAMSIS 7YO Bodybuilder) based on the RAMSIS version 3.8.30 to a permitted tolerance of ± 2 cm.

The body shape has to be implemented according to the CAD files The face is looking in the walking

direction. The PT has to be fixed in upright position. The dimensional accuracy and stability of the

PT can be verified in an easy manner may be with help of a suitable tool or template.


The reference point for the lateral position of the dummy is the HIP Point (see red circle in figure 1-

1, 1-2, 2). The same dummy posture (picture 1-1, 1-2, 2) is used for left-hand and right-hand driving

regions, as well for near- and farside test scenarios. After a collision the correctness of the PT

posture and dimension has to be checked. The most relevant PT parameters are defined in the table

below and are requested during the testing phase (wind, acceleration). Additionally to the values

mentioned in the tables, a lateral (relative to moving direction of PT) oscillation has to be

prevented: sideward tolerances +/- 5°.

Segment Unit Dim. Tol.

Body height (+shoes) mm 1800 ± 20

HIP Point height mm 923 ± 20

Shoulder width mm 500 ± 20

Shoulder height mm 1500 ± 20

Head width mm 170 ± 10

Head height mm 260 ± 10

Torso depth mm 235 ± 10

Ground Clearance mm 20 ± 5

Torso angle deg 85 ± 2

R Upper arm angle deg 60 ± 2

L Upper arm angle deg 110 ± 2

Tube in driving dir. deg 5 ± 2

Segment Unit Dim. Tol.

Body height (+shoes) mm 1154 ± 20

HIP Point height mm 607 ± 20

Shoulder width mm 298 ± 20

Shoulder height mm 920 ± 20

Head width mm 150 ± 10

Head height mm 250 ± 10

Torso depth mm 139 ± 10

Ground Clearance mm 20 ± 5

Torso angle deg 78 ± 2



Tube in driving dir. deg 5 ± 2

Figure 1-1: dimensions Adult

Figure 1-2: dimensions Child


Figure 2: Angle of tube for far and near side sceneries – Tube is leaning in driving direction


2.2 VISIBLE AND INFRARED PROPERTIES

The PT shall be look like clothed with a long-sleeved t-shirt and trousers in different colors: t-shirt

in black and jeans in blue. The clothing has to be made from tear-proofed and water-resistant

material. Skin surface parts have to be finished with a non-reflective flesh-colored texture.

The IR reflectivity from 850 to 910 nm wavelength of clothes and the skin must be within the

following range of 40% to 60%. The IR reflectivity from 850 to 910 nm wavelength of the head hairs

must be within the following range of 20% to 60%. At the selection of the clothes it has to be

ensured, that the IR reflectivity measured with the 45° probe must not differ for more than 20%

from the reflectivity measured with the 90° probe. The visual and infrared properties are defined

below:

Figure 3: Visual and Infrared Properties


The colour of stiffening ropes must be light grey and low optical reflective.

To provide robust behavior of the outer cover the textile should have following characteristic:

Area weight: < 300 g/m²

Water resistance (AATCC 127): > 600 mm

strength (ASTM D5034): > 350 lbs

light fastness (AATCC 169): > 6000 h

wear resistance ASTM (D3884): > 500 cycles

2.3 RADAR PROPERTIES

The radar reflectivity characteristics of the pedestrian targets should be equivalent to a human

being pedestrian of the same size.

2.3.1 RADAR CROSS SECTION (RCS) The radar cross section of a pedestrian depends on the observation angle and typically varies

significantly. Theoretically there is no RCS variation with the distance. However due to the field of

view of the radar sensor and the implemented free space loss compensation the measured RCS

significantly varies over distance and in near distances the pedestrian is not scanned over its

complete height. Therefore, in this document we refer to RCS as the measured RCS by radar sensor

with its specific parameter set, and it does not correspond to the physical RCS. The RCS is also

influenced by geometrical effects (i.e. multi path with constructive and destructive interferences).

Therefore during the development of pedestrian dummies it must be taken into account that the

RCS will be reviewed not only static but by a description of the RCS by closing on the PT. (see

example of the RCS distribution at 76GHz of real pedestrian in Annex A3). If the PT does not provide

a sufficient RCS and it has to be equipped with additional reflectors, they have to be distributed

throughout the whole body. On the other hand, in case the RCS of the PT is too high, absorption

material has to be distributed homogeneously over the whole body. It must be insured that the RCS

value is homogeneously distributed over the whole body of the PT. This allows achieving the effect

of decreasing RCS at a shorter distance by only partial coverage. A more precise definition must be

made individually for each frequency and sensor variant.

The radar cross section of pedestrian targets (adult and child) should stay within a defined range.

Depicted in figure 4 are example RCS boundaries for measurements (performed as described in

section 4.4 using scenario 1) with a commercial available 77 GHz sensor1 . If other sensors are used

1 Measurements performed with Continental ARS 300/301 radar sensor


or the mounting position of the sensor is different, slightly other RCS values may be obtained. In

that case an additional verification/adaption of the boundaries (figure 4) may be necessary for

validation of the PT. The boundaries of the average RCS-curves are independent from the

orientation around the vertical axes.

Figure 4: Pedestrian target RCS boundaries for measurements at 77GHz

2.3.2 DOPPLER EFFECT OF ARTICULATION

Radar sensor technology may be able to measure and detect the relative velocities of moving legs

of pedestrians. This characteristic of pedestrians will be referenced as micro-doppler in the

specifications (example of the distribution of relative velocities of a crossing pedestrian measured

by radar is provided in Annex A4).

In order to ensure a micro-doppler effect comparable to human beings the articulation of the legs

must provide the characteristics of chapter 2.4. The specified leg-movement (knee + ankle) is

evaluated by video analysis.

Additionally a homogenous distribution2 of the RCS over the whole dummy height shall be

ensured. Humanlike RCS-distribution shall be checked under static conditions (parts: lower legs,

2 A methodology to evaluate the homogenous distribution of RSC is currently under development of Uni Linz and will be introduced at

a later stage.


upper legs, feet, arms, torso and head).

2.4 ARTICULATION

Only legs articulation is requested by the dummy, since leg movement is always available at

crossing pedestrian whereas arm movement seems to be subordinated. Arm movement is

necessarily not a characteristic of human while walking/running.

In order to provide robustness and cost efficiency of the PT an articulation of hips only is preferred

in order to simulate human like leg movement. The hips are driven by electric motors.

The articulation of the legs is defined by the velocities of knee and ankle. The velocities of PTs of

the size described in chapter 2.1 must stay within the bandwidth depicted in figure 5 for an adult

and child PT.


Figure 5: Specification of knee and ankle velocity – (1 - dark blue/green, 2 - medium

blue/green, 3 - light blue/green)


In order to support repeatable articulation pattern at each test run the same articulation posture shall be ensured at the reference point (RP). The RP is defined for nearside and farside crossing scenarios at a lateral offset of 2m (hip point of PT) to the middle of the driving lane (see Figure 6). At the reference point the legs must have a posture TSw as shown Figure 6 and 7. The posture of the legs at the reference point shall be recorded by video and checked after testing. The torso shall be within +/- 10% of the target velocity when the reference point is passed.

Figure 6: Reference point for articulation (near-side and far-side scenarios)

Figure 7: Pedestrian walking phases and posture at reference point (RP) TSw

Posture at RP


The Torso and H-Point has to have a constant speed motion with low swinging. Leg movement has to have reached steady state conditions latest at a lateral offset of

3.0 m (nearside scenario, 5 kph)

4.5 m (farside scenario, 8kph)

between dummy and the middle of the lane. Articulation of the feet must be in a plane parallel to the plane defined by the dummy movement and the vertical (z) axis. Tolerance requirement: +-1°.

Leg movement shall start simultaneously with the lateral movement of the dummy. The dummy shall start from an offset of

4.0 m in nearside, 5kph scenario

6.0 m in farside, 8kph scenario

in order to be able to reach steady state leg movement at the specified lateral offsets.

2.5 MOUNTING AND GUIDANCE SYSTEM

All visible parts of the PT mounting and guidance system must be coloured in grey. In case

of a uniform background the color shade of the background can be used.

It must be ensured that the PT Mounting is not influencing radar return. Radar absorbing

material shall be used at the PT mounting to ensure that the PT mounting provide no radar

reflections.

Any supporting ropes, tubes for fixing the dummies position must be designed not to

interfere with the pedestrian emergency braking system

The distance between bottom edge of the PT and road surface has to be less than 25 mm.

Exact and reproducible positioning of the PT has to be guaranteed (± 3cm hit point).

The movement parameters of the PT has to be supplied to the vehicle

Vehicle speed up to 60 km/h and PT speed up to 20 km/h must be supported.

An active unlocking system is required to release the PT immediately before impact to

prevent/reduce severely damage by the collision.

2.6 PEDESTRIAN TARGET WEIGHT AND COLLISION STABILITY

The PT must not have any hard impact points to prevent damage of the VUT.

The PT has to be designed for a maximum collision velocitiy vVEH_COLL = 60 kph.


Max PT weight: adult: 7 kg

child: 4 kg

The PT shall be coated with a closed textile outer cover.

At repetition of tests after previous collisions the target must not show any changes in its

shape and the functionality of the articulations.

There must be a possibility to check and correct the body posture and angel of legs and

arms in an easy and practical way corresponding to the defined tolerances e.g. with the

help of a tool with a reference shape.


APPENDIX

A1 MEASUREMENT OF THE IR REFLECTIVITY

The measurement of the IR reflectivity must be carried out using a measuring device according to

the following specification.

IR Reflectivity measurement device: Spectrometer for wavelength range 800 nm – 900 nm eg: Jaz – mobiles Miniaturspektrometer von Fa. Ocean Optics, wavelength range 350 – 1000 nm, in combination with Reflexionssonde QR600-7-VIS125BX

Picture 12: Jaz Spectrometer

Calibration: Before the start of the measurement the device must be calibrated with

a reflection standard, material spectralon, reflectance 99%. The

calibration has to be verified by reflectance standards with reflectivity

of 50%, 20%.

Example of reflection standards: Labsphere Reflexionsstandards SRS-

99-020, SRS-50-020, SRS-20-020, …

Picture 13: Reflexion Standards

99% 75% 50% 20% 2%


Measurement setup: The measurement of the target must be conducted with a special

attachment which ensures a defined distance between probe and

target as defined in the following figure.

Picture 14: Measurement Probe 90°, Measurement Probe 45°

Entire test setup with Jaz-Spectrometer, reflectance probe, 90°

measuring attachment and reflection standards:

Picture 15: Complete Measurement Setup

The measurement shall be performed at three different points of the measuring object and shall be

recorded.

The resulting IR reflectivity value corresponds to the average of the three reflectivity

measurements.


A2 MEASUREMENT OF RADAR REFLECTIVITY

The measurement of the radar reflectivity must be carried out using a measurement setup

according to the following specification.

Recommended Measurement Setup

A reference measurement with a corner reflector (calibrated 10 dBsm) before and after

measurements is recommended.

Sensor

- vertical distance to ground as sensor application height 500 mm +/- 150mm - horizontal alignment +/-1 deg to center line - vertical alignment +/-1 deg to center line - 77 GHz Sensor:

Bosch MRR-SGU Continental ARS300/ARS301/ARS400 series

Car

- angular driving deviation < 2 deg (driving direction) - positioning accuracy longitudinal/lateral < 50 mm

Pedestrian Target

- positioning accuracy longitudinal/lateral < 10 mm - angular orientation deviation < 3 deg (moving direction)


Test Environment

- no additional objects/buildings in the observation area - proving ground surface completely covered with tarmac or concrete - ground conditions: flat, dry street - no metallic or other strong radar-reflecting parts in-ground or surrounding area - reference measurement with 10dBsm @ 40 m distance - corner reflector mounting height: 1m

Figure A1: Test Environment

Free space

PT

Sensor


Measurement Scenario

Scenario 1

- static PT with moving vehicle - initial distance 40 m to 4m - max. approaching speed 10 kph, no abrupt deceleration - measurement angles 90, 270 deg (static PT facing direction relative to vehicle) - averaging 5 approaches - low pass filtering using a sliding average window (+/-2.5m)

270 deg90 deg

mo

vin

g d

ire

cti

on

radar

centerline(radar boresight)

ept


A3 EXAMPLE MEASUREMENTS OF RCS

Figure A2: Example RCS of pedestrians at 76GHz

Figure A3 is providing an example of a statistical evaluation of RCS measurements of human pedestrians. The standard deviations (sigma) of RCS measurements are depicted.

Figure A3: Statistical evaluation of RCS measurements of real pedestrians3

Additional RCS measurements, evaluation methodologies and RCS-measurements of real pedestrians are presented in: http://publications.jrc.ec.europa.eu/repository/handle/JRC78619

3 Measurements and statistical evaluation performed by Bosch

http://publications.jrc.ec.europa.eu/repository/handle/JRC78619


Figure A4 provides an example of a comparison of a real human versus ACEA/4a articulated adult dummy using the evaluation methodology of Annex A2.

Figure A4: Example RCS of Articulated Adult Dummy versus real Human being (example of Bosch measurements

Figure A5 provides an example of RCS measurements of the ACEA/4A articulated adult dummy using the evaluation methodology of Annex A2. RCS evaluations of different sensor suppliers and mounting positons are depicted.

Figure A5: Example RCS Evaluation of ACEA/4a Articulated Adult Dummy

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RCS Measurements of Real Pedestrian vs. Adult Articulated Dummy

lower boundaryRCSupper boundaryRCSBosch DummySensor 1Bosch DummySensor 2Bosch, Human1,leftBosch, Human1,rightBosch, Human2,left

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Example RCS Measurements of Adult Articulated Pedestrian Dummy

Continental AverageCurveDaimler Average Curve

Bosch Average CurveVariant1Bosch Average CurveVariant 2Denso Average Curve

lower boundary RCS

upper boundary RCS


A4 EXAMPLE MEASUREMENTS OF MICRO

DOPPLER

Figure A6: Example of micro doppler4 (distribution of relative velocities) for a pedestrian with a crossing speed of 5 kph

4 Measurements performed with commercial available 77GHz radar sensor (Continental ARS Gen4); one complete crossing scene.

ABOUT ACEA

ACEA’s members are BMW Group, DAF Trucks, Daimler, Fiat Chrysler Automobiles,

Ford of Europe, Hyundai Motor Europe, Iveco, Jaguar Land Rover, Opel Group, PSA

Peugeot Citroën, Renault Group, Toyota Motor Europe, Volkswagen Group, Volvo Cars,

Volvo Group. More information can be found on www.acea.be.

ABOUT THE EU AUTOMOBILE INDUSTRY

Some 12.1 million people - or 5.6% of the EU employed population - work in the

sector.

The 3.1 million jobs in automotive manufacturing represent 10.4% of EU's

manufacturing employment.

Motor vehicles account for €396 billion in tax contribution in the EU15.

The sector is also a key driver of knowledge and innovation, representing

Europe's largest private contributor to R&D, with €41.5 billion invested annually.

European Automobile Manufacturers' Association – ACEA Avenue des Nerviens 85 | B-1040 Brussels | www.acea.be T +32 2 732 55 50 | M +32 485 886 647 | F +32 738 73 10 | [email protected] | @ACEA_eu

http://www.acea.be/

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