GB/T 44433-2024 English PDF (GB/T44433-2024)

GB/T 44433-2024: Performance requirements and testing methods for intelligent speed limit system of vehicles
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GB/T 44433-2024
GB
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 43.020
CCS T 40
Performance requirements and testing methods for
intelligent speed limit system of vehicles
ISSUED ON: SEPTEMBER 29, 2024
IMPLEMENTED ON: SEPTEMBER 29, 2024
Issued by: State Administration for Market Regulation;
Standardization Administration of the People’s Republic of China.
Table of Contents
Foreword ... 3
1 Scope ... 4
2 Normative references ... 4
3 Terms and definitions ... 4
4 General requirements ... 6
5 Performance requirements ... 8
6 Test methods ... 10
Appendix A (Normative) Functional safety requirements for systems with intelligent
speed limit control function ... 14
Bibliography ... 19
Performance requirements and testing methods for
intelligent speed limit system of vehicles
1 Scope
This document specifies the general requirements and performance requirements for
intelligent speed limit system of vehicles and describes the corresponding test methods.
This document applies to category-M and category-N vehicles equipped with intelligent
speed limit system. The technical requirements and test methods related to the
intelligent speed limit control function applies to category-M1 vehicles, and as a
reference to other types of vehicles.
Note: Where no confusion is caused, the “intelligent speed limit system of vehicles”
in this document is referred to as the “system”.
2 Normative references
The following documents are referred to in the text in such a way that some or all of
their content constitutes requirements of this document. For dated references, only the
version corresponding to that date is applicable to this document; for undated references,
the latest version (including all amendments) is applicable to this document.
GB 5768.2-2022, Road traffic signs and markings - Part 2: Road traffic signs
GB 5768.5, Road traffic signs and markings - Part 5: Speed limit
GB 21670, Technical requirements and testing methods for passenger car braking
systems
GB 34660, Road vehicles - Requirements and test methods of electromagnetic
compatibility
GB/T 39263, Road vehicles - Advanced driver assistance systems - Terms and
definitions
3 Terms and definitions
For the purpose of this document, the following terms and definitions, as well as those
given in GB/T 39263, apply.
3.1
After the system obtains the road speed limit information and determines that this
information is valid, the shortest driving distance within which the vehicle continues to
display the speed limit information in this lane.
3.4
stabilized speed
The average driving speed of the vehicle when it is in a stable driving state under the
intelligent speed limit control function.
3.5
control activated
The system meets the technical conditions specified by the manufacturer and performs
intelligent speed limit control.
3.6
intervention
The behavior that the driver actively influences the intelligent speed limit system to
perform the speed limit control function in an effective manner specified by the
manufacturer.
4 General requirements
4.1 Functional requirements
4.1.1 The system shall be able to at least identify the speed limit signs and speed limit
removal signs specified in 5.36 and 5.37 of GB 5768.2-2022.
4.1.2 The system shall have the functions of intelligent speed limit display and
intelligent speed limit information, and can also have the function of intelligent speed
limit control at the same time.
4.1.3 The system shall automatically obtain the speed limit information that the vehicle
shall comply with under the current conditions or in the lane ahead and display the
speed limit information optically. When there is no perceptible speed limit, the system
shall still issue optical display information, which shall not be digits but may be
displayed as “- -”, “?”, etc.
4.1.4 The system shall automatically obtain the speed limit information that the vehicle
shall comply with under the current conditions and monitor the vehicle’s speed in real
time. When the vehicle’s speed exceeds the speed limit, it shall issue a prompt message.
4.1.5 A system with intelligent speed limit control function shall assist the driver to
control the vehicle speed within the speed limit after the vehicle speed exceeds the
speed limit. The control activated method shall meet one of the following conditions:
a) When the vehicle speed exceeds the speed limit, the control is automatically
activated;
b) When the vehicle speed exceeds the speed limit, a speed limit control request
signal is sent to the driver, and the control is activated after the driver agrees.
4.1.6 The system shall terminate the current intelligent speed limit information signal
when the following conditions are met:
a) The vehicle is travelling at a speed lower than the speed limit;
b) A new speed limit sign appears, and the speed limit is greater than the current
vehicle speed;
c) A speed limit removal sign appears.
4.1.7 A system with intelligent speed limit control function should terminate the current
speed limit control when the following conditions are met:
a) A new speed limit sign appears, and the speed limit is greater than the current
vehicle speed;
b) A speed limit removal sign appears.
4.2 Self-checking
The system shall perform self-checking after power-on and have at least the following
self-checking functions:
a) Check whether relevant electrical components are operating normally;
b) Check whether relevant sensor components are operating normally.
4.3 Failure response
If a failure occurs during system self-checking or operation, the system shall issue a
failure indication message. The failure indication message shall at least include an
optical signal and be clearly distinguishable from the system’s speed limit display,
speed limit information and other failure indications of the vehicle.
4.4 On and off
4.4.1 The system shall automatically turn on the intelligent speed limit display and
intelligent speed limit information functions after the vehicle is powered on.
5.3 Intelligent speed limit control
When testing in accordance with 6.6, the system with intelligent speed limit control
function shall meet the following requirements in the speed limit area:
a) Activate control or send out intelligent speed limit control request signal within
1.5 seconds when the displayed speed exceeds the speed limit displayed on the
vehicle;
b) The vehicle deceleration during control activated is not greater than 3.0 m/s2;
c) Assist the driver to control the vehicle speed within the speed limit within 30
seconds after control activated, after which the displayed speed shall not exceed
the speed limit and shall not be less than the speed limit by more than 5 km/h;
d) When achieving stabilized speed control, the change in vehicle speed shall not
exceed 4% of the stabilized speed or 2 km/h, whichever is greater, and the rate
of speed change shall not exceed 0.2 m/s2 within any measurement period of not
less than 0.5 s. The stabilized speed is the average speed measured over a time
interval of at least 20 s after 10 s when the displayed speed first reaches the
speed limit.
6 Test methods
6.1 Test environment conditions
The test environment conditions shall meet the following requirements:
-- Horizontal visibility greater than 1 000 m;
-- Ambient temperature at -20 ℃ ~ 45 ℃;
-- Average wind speed at least 1 m above the ground not more than 5 m/s, and
the maximum wind speed not more than 10 m/s;
-- Test carried out on a level, dry concrete or asphalt pavement with good
adhesion;
-- Speed limit sign located on the side of the road or above the lane and meeting
the requirements of 5.36 in GB 5768.2-2022;
-- Size, shape, color and installation of speed limit signs meeting the
requirements of GB 5768.2-2022 and GB 5768.5.
6.2 Test vehicle requirements
6.2.1 Vehicle load
The test shall be carried out in the state of the total mass of the test vehicle’s complete
vehicle kerb mass plus the driver and test equipment. The total mass of the driver and
test equipment shall not exceed 150 kg. The load state of the test vehicle shall not be
changed after the test starts.
6.2.2 Tires
The tires used in the test shall be run-in to a normal state, and the tire pressure shall be
the cold-state inflation pressure recommended by the vehicle manufacturer.
6.2.3 Brakes
Before the intelligent speed limit control test, the brakes of the test vehicle shall be run-
in in accordance with the provisions of GB 21670.
6.3 Requirements for test equipment
The test data collection and recording instruments shall at least meet the following
accuracy requirements:
a) The requirement for speed accuracy is 0.1 km/h;
b) The requirement for acceleration accuracy is 0.1 m/s2;
c) The requirement for time accuracy is 0.1 s;
d) The requirement for distance accuracy is 0.03 m.
6.4 Intelligent speed limit display test
6.4.1 Display distance threshold test
6.4.1.1 Install speed limit sign on the test lane in accordance with the requirements of
GB 5768.5, and conduct tests in sequence at the speed limits shown in Table 1.
6.4.1.2 The test vehicle shall, at least 2 seconds before the test, drive towards the speed
limit sign at a constant displayed speed lower than the speed limit by (5±2) km/h in the
test land. If the maximum speed of the test vehicle is lower than the speed limit, the test
vehicle shall, at least 2 seconds before the test begins, drive towards the speed limit sign
at its maximum speed in the test lane.
6.4.1.3 The test shall commence when the front plane of the test vehicle is 100 m away
from the speed limit sign. When the distance travelled by the front plane of the test
vehicle after crossing the plane where the speed limit sign is located exceeds the
threshold of display distance specified in Table 1, the test ends.
6.4.1.4 From the beginning to the end of the test, the driver shall not make any
adjustments to the test vehicle except for slight steering adjustments to prevent the
vehicle from deviating from the direction.
Appendix A
(Normative)
Functional safety requirements for systems with intelligent speed limit control
function
A.1 General
This Appendix does not target the nominal performance of the system, nor does it serve
as specific guidance for the functional safety development of the system. Instead, it
specifies the methods to be followed in the design process and the information to be
available during system verification and validation to demonstrate that the system can
achieve the functional concept and functional safety concept in both normal operation
and failure conditions and meet all applicable performance requirements specified in
this document.
A.2 Documentation
A.2.1 Requirements
There shall be documentation describing the functional concept of the system, the
functional safety concept, safety strategy, development process and methods developed
to achieve the safety goals, so as to demonstrate that the system:
a) can achieve the functional concept and functional safety concept in both non-
failure and failure conditions through design;
b) meets the performance requirements specified in this document under non-
failure and failure conditions;
c) development processes and methods are applicable.
A.2.2 System description
A.2.2.1 The functional concept of the system, i.e., the purpose and functional
description list, shall be described.
A.2.2.2 The scope of the system shall be defined, its subsystems and elements shall be
clearly defined, and the external systems or elements with which it interacts shall be
identified.
A.2.2.3 The operating conditions and constraints of the system shall be defined, and the
limits of the effective working range shall be stated for the corresponding system
functions.
A.2.3 System layout and schematic diagram
A.2.3.1 System component list
A component list shall be provided, which shall include all component elements of the
system and shall also list other vehicle systems required to achieve the relevant control
functions.
A system layout and schematic diagram shall be provided based on these component
elements, which shall clearly show the component distribution and interconnection.
A.2.3.2 Element function
The functions of each element of the system shall be summarized and the signal
connections between the element and other elements or other systems in the vehicle
shall be shown. A labeled block diagram or other schematic diagrams may be used, or
the illustration may be aided by a chart.
A.2.3.3 Interconnection
The interconnections among the electronic transmission chain, hydraulic transmission
chain and mechanical connection devices within the system shall be respectively
explained using circuit diagrams, piping diagrams and layout diagrams.
A.2.3.4 Signal flow, operating data and priorities
There shall be a clear correspondence between the transmission chains, signals and
operating data between elements.
Priority shall be established for signals and operational data within multiple data
channels if the priority affects performance or safety as described in this document.
A.2.3.5 Element identification
Each element shall be clearly and unambiguously identifiable (e.g., identification of
hardware, identification of software content, or software output) and provided with a
corresponding description.
When an element or a single processor that integrates multiple functions appears
multiple times in a block diagram, only one hardware identification marking is used for
clarity and ease of explanation. Identification markings shall be used to confirm that
the device supplied is consistent with the corresponding documentation.
The identification marking shall clearly indicate the versions of the hardware and
software. If the functions described in this document are changed due to version
changes, the identification marking shall be chan...