JP-7855144-B2 - Method for configuring parameters for formations moving in close proximity and server

JP7855144B2JP 7855144 B2JP7855144 B2JP 7855144B2JP-7855144-B2

Inventors

ブティエ、アルノー
ギエ、ジュリアン

Assignees

ミツビシ・エレクトリック・アールアンドディー・センター・ヨーロッパ・ビーヴィ

Dates

Publication Date: 20260507
Application Date: 20230501
Priority Date: 20220915

Claims (15)

A computer - implemented method for configuring a set of parameters for at least two moving formations , each of which comprises a plurality of separate communication nodes, the set of parameters comprising at least one pre-parameter, the pre-parameter corresponding to a formation parameter or a network parameter of the formation, the formation parameter of the formation defining the geometric arrangement of the communication nodes of the formation, the network parameter of the formation defining the communication resources allocated to the formation for exchanging data over a wireless link, the pre-parameter having a predetermined value, and a predetermined change in the communication environment of the formation is about to occur, the set of parameters for the formation, Control parameters of the control algorithm used by the formation to maintain the geometric arrangement, The wireless link between the communication nodes of the formation, which is used for exchanging data related to the control algorithm, and which comprises communication parameters constituting the wireless link, It further includes, The aforementioned method , With respect to the aforementioned pre-parameters, the range of acceptable performance values based on the corresponding pre-parameter values is obtained, When considering that a change has occurred in the communication environment of the formation, the values of the control parameters and communication parameters of the formation that enable the achievement of the allowable performance value within the range are searched, If it is not possible to achieve the allowable performance value within the range, the updated range of the allowable performance value is searched for, which allows for the determination of the values of the control parameters and communication parameters that enable the achievement of the allowable performance value when considering the change in the communication environment. Based on the values of the control parameters and communication parameters that enable the achievement of the allowable performance value within the updated range of the allowable performance value, the updated value of at least one prior parameter is determined. Methods that include...
The method according to claim 1, wherein the range of the allowable performance values of the formation parameters corresponds to the range of the allowable control performance values of the control algorithm used by the formation, and/or the range of the allowable performance values of the network parameters corresponds to the range of the allowable resource usage performance values for the use of the allocated communication resources by the formation.
The method according to claim 2, wherein the set of parameters has a plurality of pre-parameters, each of which has one formation parameter and at least one network parameter for all of the formations, and if it is not possible to find values for the control parameter and the communication parameter of the formation that enable the achievement of the acceptable performance value within the range, the search of the updated range includes reducing the acceptable control performance value of at least one of the formations.
The method according to claim 3, wherein exploring the updated range includes first reducing the allowable control performance value and then reducing the allowable resource utilization performance value as necessary .
The method according to claim 2, wherein the set of parameters has a plurality of pre-parameters, each of which has one formation parameter and at least one network parameter for all of the formations, and if it is not possible to find values for the control parameter and the communication parameter of the formation that enable the achievement of the acceptable performance value within the range, the search of the updated range includes reducing the acceptable resource utilization performance value of the formation.
The method according to claim 5, wherein exploring the updated range includes first reducing the allowable resource usage performance value, and then reducing the allowable control performance value as necessary.
The method according to any one of claims 3, 4, and 6, wherein exploring the updated range by reducing the allowable control performance value of the formation includes using the same reduction coefficient for all or more of the formations.
The method according to any one of claims 2 to 6, wherein the allowable control performance value of the control algorithm represents the allowable convergence speed value of the control algorithm.
The method according to any one of claims 2 to 6, wherein the allowable resource usage performance value represents the global interference level generated by all the formations when using the allocated communication resources.
The formation parameters of the aforementioned formation are: The distance between the communication nodes in the aforementioned formation, The geometric arrangement of the aforementioned formation and The speed of the communication nodes in the aforementioned formation, A method according to any one of claims 1 to 6, which represents at least one of the following.
The allocated communication resources included in the aforementioned network parameters are At least one frequency bandwidth, At least one spreading code or scrambled code, At least one temporal pattern, The method according to any one of claims 1 to 6, wherein the method is any one of the following.
The method according to any one of claims 1 to 6, which is performed by a configuration server that is included in or separate from the formation, at least one of the communication nodes of the formation.
A computer program product comprising instructions that, when executed by at least one processor, configure the at least one processor to perform the method according to any one of claims 1 to 6.
A configuration server comprising at least one processor, at least one memory, and at least one communication module, wherein the at least one processor is configured to perform the method according to any one of claims 1 to 6.
The configuration server according to claim 14, which is included in or separate from at least one communication node of the formation.

Description

This disclosure relates to a communication system, and more specifically, to a method for configuring a set of parameters for at least two formations of communication nodes moving in close proximity to each other, and to a server. Many applications benefit from constructing formations consisting of multiple vehicles. These vehicles must follow the same trajectory as a whole while coordinating to maintain a desired geometric arrangement among them. Moving in formation offers many advantages over non-cooperative systems, including reduced system costs, increased system robustness and efficiency, and redundancy, reconfigurability, and structural flexibility [Chen2005]. In particular, platooning is seen as a very promising application where multiple vehicles (for example, in a single lane) are required to travel at a desired speed while maintaining a predetermined distance between them. Whether it's cars, trucks, robots, or even airplanes, platooning can bring significant benefits in terms of power consumption, passenger comfort, and traffic flow. Other types of formation applications include satellite clusters, security, search and rescue, and drone swarms for agriculture. To maintain the geometric arrangement of a formation, the dynamics of the vehicles in the formation are typically handled using control algorithms that require data exchange between communication nodes built into the vehicles. For example, a platoon usually means that the lead vehicle transmits its acceleration and velocity to the following vehicles, and each vehicle transmits its position and velocity to its neighbors (see, e.g., [Sybis2019]). Then, for example, a consensus algorithm can be used to keep the vehicles equidistant from each other. Most formation applications rely on wireless links due to their mobility requirements. Communication over wireless links is prone to errors stemming not only from physical layer issues (additional noise, path loss, shadowing, fast fading, phase noise, etc.) but also from higher-layer issues (collisions caused by hidden node effects in Carrier Sensing Multiple Access (CSMA) schemes or distributed scheduling). Latency, while partly caused by physical layer factors (transmission delay, packet duration, etc.), is mostly caused by higher-layer factors (scheduling policies, random access schemes, etc.). Since control algorithms rely on data exchange between communication nodes, the loss of data packets clearly negatively impacts the performance of the control algorithm. Packets can be lost due to a lack of communication resources. Due to the limited radio frequency, wireless systems are designed to operate with limited bandwidth. Therefore, regardless of the transmission technology used, communication nodes will only have access to a limited number of communication resources per unit of time (either at the physical level or at the logical level, where operators allocate only a subset of the total available resources to specific applications). When a single formation of vehicles is moving while maintaining a predetermined geometric arrangement between vehicles (typically a 1D configuration with predetermined inter-vehicle distances and speeds) using a control algorithm (such as a consensus algorithm) and limited communication resources, it is crucial to ensure that the control algorithm can effectively control the shape of the geometric arrangement and/or its speed at a sufficient convergence rate. The convergence rate of the control algorithm depends, in particular, on the packet loss rate (see, e.g., [Sybis2019]). On the other hand, the formation needs to be able to anticipate changes in the communication environment that may prevent the geometric arrangement of this formation from achieving a sufficient convergence speed. Such changes in the communication environment can occur, for example, when different formations approach each other and use the same communication resources to exchange data related to their respective control algorithms. As these formations move within each other's radio coverage, their communication nodes compete for access to the same communication resources, leading to increased mutual interference and packet loss. An example of formations moving within radio proximity and potentially competing for the same communication resources is a platoon of vehicles crossing or overtaking each other on a highway. This is a schematic diagram of two formations corresponding to separate platoons of vehicles.This is a schematic diagram of two formations corresponding to separate platoons of vehicles.This diagram illustrates the main steps in configuring the set of parameters for a formation.This is a schematic diagram of the server configuration.This figure shows an example of a Pareto frontier in a multi-objective optimization problem.This figure shows examples of various selection policies for choosing points on the Pareto frontier.This figure shows examples of various selection policies for cho