JP3205015B2 - Control device for autonomous vehicle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ring type network.
Time determination method, and communication network
The present invention relates to a control device for an autonomous traveling vehicle used .

[0002]

2. Description of the Related Art In a conventional control apparatus for an autonomous vehicle, for example, Japanese Patent Application Laid-Open No. 64-26913, a vehicle is controlled by acquiring an external situation using a camera and performing environment recognition based on the acquired situation. Like that. in this way,
In an autonomous vehicle, processes such as environment recognition, situation judgment, and vehicle control are required, and an interface with a driver is also an important factor.

[0003]

SUMMARY OF THE INVENTION Advances in microcomputer technology, especially when multi-microcomputer system technology using the same is applied to this autonomous vehicle, an environment recognition subsystem, a situation determination subsystem, and a vehicle control subsystem It is conceivable to divide the autonomous driving system into four subsystems such as a driver interface subsystem and to process these in parallel. In order to achieve advanced functions throughout the system, close communication between all of these subsystems is required. Also, with current processor technology,
Due to its capacity issues, each subsystem itself is also composed of multiple processors.

[0004] Therefore, when processors that require communication in the autonomous driving system are connected to each other, an extremely complicated network configuration is required as a whole. As a result, the control of the entire autonomous driving system becomes complicated, and the design and production costs for realizing hardware and software increase, and at the same time, it becomes difficult to secure reliability. Therefore, the present invention
Is a control system for an autonomous vehicle consisting of multiple subsystems.
Of communication information transmitted and received between
The purpose is to ensure reliability .

[0005]

Means for solving the problem and its operation The present invention for achieving the above object is a control device comprising a plurality of subsystems for controlling the traveling of an autonomous traveling vehicle . Operation of communication control unit and driver
And a means for presenting information to the driver.
A driver interface subsystem having
Communication control unit and external recognition to recognize the external world
Environment recognition subsystem having means and a third communication system
Control unit, means for detecting the condition of the vehicle, and operation of the vehicle.
A vehicle control subsystem having means for controlling the movement;
A fourth communication control unit and the environment recognition subsystem
Recognition result and control by the vehicle control subsystem
Means for creating a travel plan based on the result.
Supply this travel plan to the vehicle control subsystem
Situation determination subsystem and first to fourth communication controls
Communication as a communication node that monitors the communication status of the unit
A monitoring subsystem; and the first to fourth communication control units.
Communication unit, as well as a communication unit in which the communication nodes are connected in a ring.
Communication line and use that communication line.
Therefore, when information is transmitted and received between the respective subsystems,
In the communication monitoring subsystem, the communication node
The communication module sends communication information transmitted from each of the subsystems.
Receiving at least the communication information.
Check whether the
If not received, the communication information is passed and received.
When the communication information has been transmitted, the communication information is discarded .

In a preferred embodiment, the communication information includes
Is the communication control unit of the transmission source that transmitted the communication information.
Source information that can identify the
Destination information that can identify the communication control unit of the destination,
The communication control unit of the transmission destination receives the communication information.
Identification information that can identify whether the
In the communication lines connected in a ring shape,
When the communication control unit of No. 4 receives the communication information,
The communication information is the communication information addressed to the own communication control unit.
Regardless of whether or not there is, the communication information is transmitted to the communication line.
The communication control of the transmission source.
The unit transmits the communication information when transmitting the communication information.
As the identification information included in the communication information,
That the signal has not been received by the communication control unit.
A first identifier that represents the destination information.
Then, information for specifying the own communication control unit is set, and
The communication in which a first identifier is set as the identification information.
The communication control unit of the transmission destination that has received the communication information
As the identification information, the reception by the own communication control unit
A second identifier indicating that the
The communication information in which the identifier 2 is set is transmitted to the communication line.
When transmitting, the communication node transmits the communication information.
Information, the identification information included in the communication information is received.
When the first identifier is set as information,
The received communication information is transmitted to the communication line on the communication line.
Transfer to the communication control unit connected next to the
If the second identifier is set, the communication
It is characterized by discarding information .

[0007]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 schematically shows the function of the autonomous traveling vehicle system of this embodiment. The outside world of this system is the environment, the driver and the vehicle. This autonomous vehicle assists the driver's driving so that the driver can drive easily.
The information is transmitted to the driver by the human interface system 1. The environment such as obstacles and roadsides is recognized by an environment recognition system 2 having a visual recognition device or the like as a visual system. The result of the environment recognition performed by the system 2 is sent to the situation determination system 4. The system 4 judges the situation based on the recognition result of the environment, the judgment of the driver, and the traveling information of the vehicle held by the vehicle control system 3. The result of this situation determination is sent to the vehicle control system 3, which controls, for example, steering and braking. The vehicle control system 3 sends monitoring results to the environment recognition system 2, the situation determination system 4, and the human interface system 1 while constantly monitoring the running state (running speed and running direction) of the vehicle. The human interface system 1 transmits various messages to the driver while monitoring the operation state of the driver.

When the travel control device for an autonomous vehicle is divided into four functions of a human interface, environment recognition, situation judgment, and vehicle control as shown in FIG. 1, each of these four functional subsystems Those that are combined so that other functional subsystems need the collected data, the functions themselves are independent. That is, the individual functional subsystems of the system of FIG. 1 can be replaced by a communication network system.

FIG. 2 is a block diagram in the case where the system shown in FIG. 1 is realized as a combined system of a plurality of networks. The four subsystems in FIG. 1 are connected to a ring communication line 10 via respective communication units. If the information generated in each of these subsystems 1, 2, 3, 4 is needed in another subsystem, the communication unit of the sending subsystem, the line 10 and the communication unit of the recipient And the information is sent via.

FIG. 3 illustrates the functions performed by these four subsystems. That is, the human interface subsystem 1 performs various monitor display controls.
The environment recognition subsystem performs white line recognition, obstacle recognition, and running vehicle (forward vehicle) tracking. The vehicle control subsystem 3 performs motion control, steering, and speed control. The situation determination subsystem 4 includes a driver's instruction from the human interface subsystem 1, an environment recognition result (white line, roadside, obstacle) from the environment recognition subsystem, a speed detected by the vehicle control subsystem 3, a steering direction, and the like. Then, a cruise plan (driving plan) is created. The created cruise plan is sent to, for example, the environment recognition system 2 and the vehicle traveling control subsystem 3. For example, environment recognition subsystem 2
Let us distinguish between those that can become new obstacles in the environment and those that cannot be when obeying the sent plan. Further, the vehicle control subsystem 3 performs operations such as turning the steering wheel, reducing the speed, and controlling the brake.

If a network is configured as shown in FIG. 2 and further, as shown in FIG. 3, each subsystem only needs to have one communication unit for communicating with another subsystem. In particular, the subsystems 1, 2, and 3 respectively include a driver, an environment, and an external input / output that interfaces with the vehicle.
It would be good to have one by one. When an autonomous vehicle system is constructed by such a network, all information in the system is communicated via the line 10 on the ring, so that monitoring of the operation status is sufficient only by monitoring the line 10.

As suggested in FIG. 3, the function of each subsystem (for example, a higher-level function such as an environment recognition function)
Can be considered as a set of a plurality of lower functions (for example, lower functions such as white line recognition and obstacle recognition).
Each of these sub-functions is a unique function as one function. Therefore, each of these subfunctions is
It can be realized as one network. From such a viewpoint, the network system of FIG.
It is a reconfiguration of the system of FIG. That is, the line 10 forms a parent network ring. This parent ring 10 includes units 10-1, 10-2, 10-3, 1
Child network rings 30, 40, 5 via 0-4
0, 60 are connected. Each lower sub-function is CPU
Is executed. And, if necessary,
For example, the child network ring 50 includes the unit 10-
5, a grandchild network ring 70 is connected. In this way, by further subdividing the roles and functions in each subsystem, input / output and communication can be systematized. In addition, by taking such a structure,
All the processor units need only have one upper communication line and one lower communication line as communication lines. If such a processor is used for white line recognition, communication with other subsystems is performed while performing white line recognition processing.

[0013] Thus, by layering the network, there is an advantage that it is not necessary to prepare various processor specifications for each unit depending on the communication mode and the input / output. By the way, in each network in the system, since each processor independently performs processing, reliability of system operation as a whole becomes a problem. In other words, since each processor exchanges information asynchronously with other processors in order, the other units detect a problem in one unit in the whole system, and the whole system goes into guaranteed operation. It becomes difficult to enter. As a result, the reliability of the entire system decreases.

Therefore, the system shown in FIG.
A network system as shown in FIG. 6 is proposed. This network system is characterized in that the system of FIG. 3 further includes a discard / monitoring node. This node collects communication information transmitted from each unit, thereby enabling the operation state of each unit to be monitored.
If an abnormality is found in the operation of a certain unit, the discarding / monitoring node 5 intervenes in the network and transmits a message for dealing with the abnormality, thereby realizing the abnormality diagnosis and the guarantee operation.

FIG. 7 shows a unified format of a message packet transmitted to the network of FIG. Each packet includes a “communication information” portion and a “received” flag. The “communication information” portion includes communication data, information indicating a source unit, information indicating a destination unit, and transmission time information. In the ring network, the source unit sends a new packet with the “received” flag set to “0”. The packet is received by the immediate neighbor, and the neighbor also sends out to the neighbor. On the other hand, the discarding / monitoring node monitors all the packets circulating in the network, and sends the packet whose flag is not "1" to the adjacent unit as it is. In this way, when packets are successively sent to adjacent units, the packets reach the unit to be received. The unit at the receiving end can confirm whether or not the packet is to be received by itself, based on “information indicating the receiving unit” in the “communication information” portion. Thus, when the packet to be received reaches itself, the unit sets the "received" flag in the packet to "1" and sends the packet to the unit next to itself again. I do. By doing so, the packet whose “received” flag is set to “1” comes to the discard monitoring node 5 soon. The node 5 always checks whether or not the “received” flag of the received packet is “1”. If the “received” flag is “1”, the packet is transmitted by all units. Assuming that the packet has been received, the packet is discarded.

An abnormality in the system can be attained by checking the "transmission time" and the "received" flag.
That is, if the “received” flag has not been set yet after a predetermined time has elapsed from the transmission time, the discard monitoring node 5 determines that an error has occurred in the system. In such a case, all information arriving at the discard monitoring node 5 itself is suspended and urgent information is transmitted. As a result, the entire system can start the guaranteed operation at high speed.

FIG. 8 shows a case where a plurality of discard monitoring nodes 5 are provided in the network. In the example of FIG. 8, two monitoring nodes (# 1 and # 2) are connected to the network 10. Node # 1 is assigned to, for example, CPUs 2, 3, and 4, and node # 2 is assigned to, for example, CPUs 0 and 1. FIG. 9 shows a format of a packet flowing through the network of FIG. The difference from the format of FIG. 7 is that a “monitoring 1 flag” and a “monitoring 2 flag” are added. These two flags are added when each unit transmits a packet. That is, CPU2,
When packets 3 and 4 send packets, the "monitoring 1 flag"
To “1”. When the CPUs 0 and 1 transmit a packet, the "monitoring 2 flag" is set to "1". The # 1 node discards the packet only when the “received flag” and the “monitoring 1 flag” are “1”. The node # 2 discards the packet only when the “received flag” and the “monitoring 2 flag” are “1”. Thus, node # 1 is the CP
Only the packets from U2, 3, and 4 are discarded, and node # 2 discards the packets of CPUs 0 and 1.

Next, monitoring of time in the network system shown in FIG. 3 or FIG. 6 will be described. As described above, in the systems shown in FIGS. 3 and 6, since each unit generates data asynchronously, when a certain unit receives a packet, it is necessary to clarify when the packet occurred. In many cases. That is, in image recognition and vehicle control, since the order of information generation is important, recognition and control cannot be performed if the order of reception is out of order. In an asynchronous information generation system, each unit must operate according to a common time. Therefore, a method of calibrating time in the network systems of FIGS. 3 and 6 will be described below.

For convenience of explanation, as shown in FIG.
Five of subsystems are connected to, those subsystems, as shown in FIG. 10, CPU ₀ to CPU ₄
It is indicated by Now, as shown in Figure 10, CPU ₀
Sends the first calibration signal clockwise into the network 10. Then, the signal from CPU ₀ is
₁ is received by to CPU _4, the reception time for each CPU until it is received further in the original CPU _0, as shown in FIG. 12, t
_1, the _{t 2, t 3, t 4} , t 5.

Then, at time t ₅ , CP
When a second calibration signal is sent counterclockwise from U ₀ , C
PU ₄ , CPU ₃ , to the CPU ₀ , the reception time is t ₆ , t ₇ , t ₇ , as shown in FIG.
_8, the t _9, t _10. Although there is a slight difference in the processing time in each unit, when the calibration signal is sent clockwise and counterclockwise, each unit (for example, CPU ₁ ) sends the first calibration signal. The time (t ₁ -t ₀ ) required to receive from the immediately preceding unit is determined by the unit (CPU ₁ ) sending the second calibration signal to the next unit (C
PU ₀₎ to send it the next unit from the should equal to the time (t ₁₀ -t ₉₎ to the reception. This relationship should hold for all CPUs. Accordingly, in a unit CPU _n, the time of receiving the first calibration signal (e.g., a t _xn) stores the next time you receive a second calibration signal (e.g., a t _Yn) Is stored. Then, when the unit CPU _n performs _{time-setting, t xn + (t Yn -t} xn) / 2 to be the current time. This is because such time adjustment is equivalent to time adjustment of each unit along the line 200 in FIG.

The method shown in FIG. 12 is characterized in that all units simultaneously adjust the time. If time adjustment is to be performed using only one calibration signal, for example, a method of adding time data to the signal and sending the data to each unit may be considered. However, in this method, it takes a certain time for one unit to send the data to the next unit, and the processing time is often unknown. However, in the method of the present embodiment, even if the processing time is unknown, there will be no difference between the processing time of the first calibration signal and the processing time of the second calibration signal. It is. The time adjustment of this embodiment is effective when the system is started.

[0022]

As described above, according to the present invention,
For autonomous vehicle control system consisting of multiple subsystems
Of communication information transmitted and received between subsystems in
Nature can be secured .

[Brief description of the drawings]

FIG. 1 is a block diagram showing four functions in an embodiment system to which the present invention is applied.

FIG. 2 is a diagram showing a system configuration when each function of the system in FIG. 1 is formed by a network.

FIG. 3 is a diagram further subdividing the functions of each subsystem in the system of FIG. 2;

FIG. 4 is a system block diagram when the system of FIG. 3 is designed with a hierarchical network structure.

FIG. 5 is a diagram showing a configuration of a CPU used in the network system of FIG. 4;

FIG. 6 is a diagram showing a network system formed by adding a monitoring node to the network system of FIG. 3 in order to facilitate management of communication packets exchanged between subsystems.

FIG. 7 is a view for explaining the format of a packet used in the network of FIG. 6;

FIG. 8 is a configuration diagram of a system in which a plurality of monitoring nodes are provided by further developing the network of FIG. 6;

FIG. 9 is a view showing a format of a packet used in FIG. 8;

FIG. 10

FIG. 11

FIG. 12 is a view for explaining a method of configuring a reference time in each subsystem of a network if the subsystem is composed of a plurality of subsystems.

[Explanation of symbols]

1 Human Interface Subsystem, 2 Environment Recognition Subsystem, 3 Vehicle Control Subsystem, 4 Situation Determination Subsystem, 5 Monitoring Node, 10, 30, 40, 50, 60, 70 Communication Line, 10-1, 10-2, 10-3, 10-4, 10-5
communication unit

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁷ , DB name) G05D 1/00-1/12 H04Q 9/00-9/16 H04L 11/00

Claims (2)

(57) [Claims] 1. A control device comprising a plurality of subsystems for controlling the travel of an autonomous vehicle, comprising: a first communication control unit; means for monitoring operation of a driver; and presenting information to the driver. A driver interface subsystem having means, a second communication control unit, an environment recognition subsystem having external environment recognizing means for recognizing the external world, a third communication control unit, and detecting a state of the vehicle and means for, based on the vehicle control subsystem and means for controlling the motion of the vehicle, and fourth communication control unit, the control result and the recognition result by said environment recognition subsystem by the vehicle control subsystem running Means for creating a plan,
Monitor the communication state of the situation determination subsystem that supplies this travel plan to the vehicle control subsystem and the first to fourth communication control units.
A communication monitoring subsystem as a communication node that performs communication, the first to fourth communication control units , and the communication
By node and a communication line which is connected in a ring, by utilizing the communication line, wherein along with transmission and reception of information between the subsystems is performed in the communication monitoring subsystem, the communication node receives the communication information transmitted from each subsystem, in which case the communication information is checked whether it is received in <br/> subsystem should receive at least said communication information has not been received Characterized in that the communication information is passed and the communication information is discarded if the communication information is received.
Control device for traveling vehicle . And transmitting said communication information to said communication information.
Source information that can identify the communication control unit of the
Communication control unit of the destination to receive the communication information.
Destination information that can specify the destination, and communication control of the destination
Can identify whether the unit has received the communication information
Identification information is included in the communication line connected in a ring shape.
The fourth to fourth communication control units receive the communication information.
When the, the communication information of the communication information self-communication control unit destined
The communication information is transmitted to the communication
And the communication control unit of the transmission source transmits the communication information.
The identification information included in the communication information.
And the reception by the communication control unit of the transmission destination is not yet completed.
Set the first identifier to indicate that no
Ri, information identifying the own communication control unit as the transmission destination information
Information is set, and a first identifier is used as the identification information.
The communication control of the transmission destination that has received the set communication information
The control unit uses its own communication control unit as the identification information.
A second identifier indicating that the
And the communication information in which the second identifier is set.
Is transmitted to the communication line, the communication node, when receiving the communication information, included in the communication information
The first identifier is set as the identification information
In this case, the received communication information is transmitted through the communication line.
Communication control unit connected next to said communication node
And if the second identifier is set,
Discarding the communication information.
The control device for an autonomous traveling vehicle according to any one of the preceding claims.