control device

Abstract

To provide a control device capable of reducing a calculation load required to make a track plan and a speed plan.SOLUTION: A control device 10 includes: a first planning unit 13 that makes a track plan which is a plan indicating a lateral position of a vehicle MV at each point, when the vehicle MV is caused to travel along a predetermined route; a second planning unit 14 that makes a speed plan which is a plan indicating a traveling speed of the vehicle MV at each point, when the vehicle MV is caused to travel along the route; and a braking / driving force control unit 15 and a steering control unit 16 which cause the vehicle MV to travel according to both the track plan and the speed plan. After the first planning unit 13 makes the track plan, the second planning unit 14 c makes the speed plan as a plan for causing the vehicle MV to travel in accordance with the track plan.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a control device for a moving object. [Background technology]

[0002] Technologies for automating part or all of the driving operations of a vehicle are being developed. Such technologies include those called Advanced Driver Assistance Systems (ADAS) and those called Autonomous Driving (AD). For example, Patent Document 1 listed below describes a technology that sets an appropriate target speed according to the passenger's preferred speed and automatically adjusts the engine's driving force, etc., so that the actual speed becomes the target speed.

[0003] Technological advances in this field have been remarkable, and development competition is intensifying not only in Japan but around the world. In recent years, infrastructure has also been developed, making it possible to obtain the information necessary for control from intelligent transport systems and to use detailed map data, including topographical information. Furthermore, advances in individual technological developments, such as actuator control and electric brakes, have made it possible to perform detailed control of vehicle movement.

[0004] As the information available for control has become more detailed and diverse, and advances in hardware technology have increased the degree of freedom in control, it is expected that more advanced control will become possible in the future. For example, it is expected that control will be realized that will further improve vehicle driving performance, ride comfort, energy efficiency, etc. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 4513247 Summary of the Invention [Problem to be solved by the invention]

[0006] The inventors are currently studying ways to reduce the energy required for vehicle travel by optimizing not only the automatic adjustment of the vehicle's travel speed but also the automatic adjustment of the vehicle's travel path. Note that the term "path" here refers to the path that indicates which portion of a specific road in the width direction the vehicle will travel on when traveling on that road. Therefore, "automatic adjustment of the path" refers to the automatic adjustment of the vehicle's lateral position while traveling.

[0007] One method for enabling such control is to create both a speed plan, which indicates how the vehicle's traveling speed should be changed over a predetermined period of time in the future, and a trajectory plan, which indicates the trajectory along which the vehicle should travel over that predetermined period of time, and then run the vehicle according to both the speed plan and the trajectory plan. If both the speed plan and the trajectory plan can be optimized and created so that energy consumption is as low as possible, the energy efficiency of the vehicle can be improved.

[0008] For example, to create the above-mentioned speed plan, it is necessary to formulate and solve an optimization problem while taking into account multiple factors, such as not only vehicle dynamics but also powertrain efficiency characteristics of the engine, motor, etc., and external information such as the gradient and curvature of the road. However, the more information available for control, the greater the computational load required to achieve control using that information. Therefore, even when creating only the speed plan, a significant amount of computational resources is required, which may be difficult to achieve with a control device that can be installed in the vehicle. Naturally, if one attempts to optimize not only the speed plan but also the trajectory plan, the required computational resources become even more enormous.

[0009] An object of the present disclosure is to provide a control device that can reduce the computational load required to create a trajectory plan and a velocity plan. [Means for solving the problem]

[0010] A control device according to the present disclosure is a control device (10) for a moving body (MV), and includes a first plan creation unit (13) that creates a trajectory plan, which is a plan indicating the lateral position of the moving body at each point when the moving body travels along a predetermined route, a second plan creation unit (14) that creates a speed plan, which is a plan indicating the traveling speed of the moving body at each point when the moving body travels along the route, and traveling control units (15, 16) that cause the moving body to travel in accordance with both the trajectory plan and the speed plan. After the first plan creation unit creates the trajectory plan, the second plan creation unit creates a speed plan as a plan for traveling the moving body in accordance with the trajectory plan.

[0011] A control device configured as described above first creates a trajectory plan, and then creates a velocity plan as a plan for moving the moving object according to the trajectory plan. In other words, instead of simultaneously creating both a trajectory plan and a velocity plan by solving a complex optimization problem, the control device first creates only the trajectory plan, independent of the velocity plan. This reduces the computational load required to create the trajectory plan. Furthermore, since the velocity plan is created on the premise that the moving object will travel according to the existing trajectory plan, the computational load required to create the velocity plan can also be reduced.

[0012] Although the effect of improving energy efficiency is smaller than when both trajectory planning and velocity planning are performed simultaneously due to the combined calculation, the significant reduction in the required calculation load can provide significant advantages, such as enabling the entire control device to be configured as an on-board ECU. [Effects of the Invention]

[0013] According to the present disclosure, a control device is provided that can reduce the computational load required to create a trajectory plan and a velocity plan. [Brief explanation of the drawings]

[0014] [Figure 1]FIG. 1 is a block diagram that schematically shows the configuration of a control device according to this embodiment. [Figure 2] FIG. 2 is a flowchart showing the flow of processing executed by the control device. [Figure 3] FIG. 3 is a diagram for explaining an example of a trajectory plan. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, the present embodiment will be described with reference to the accompanying drawings. To facilitate understanding of the description, the same components in the drawings will be denoted by the same reference numerals as much as possible, and duplicated descriptions will be omitted.

[0016] The control device 10 according to this embodiment is configured as a device for controlling the operation of a vehicle MV. In FIG. 1, the vehicle MV to be controlled is depicted as a schematic block. The vehicle MV is, for example, an electric vehicle, and is equipped with a rotating electric machine (not shown) as a device for generating the driving force required for traveling. Alternatively, the vehicle MV may be a vehicle that runs using the driving force of an internal combustion engine. Furthermore, the vehicle MV may be a hybrid vehicle that can run using the driving force of both an internal combustion engine and a rotating electric machine.

[0017] The vehicle MV of this embodiment is configured as a so-called "automated driving vehicle" in which all driving operations are performed automatically. Alternatively, the vehicle may be configured to automatically perform only some of the driving operations (accelerator operation), braking operations (brake operation), and steering (handle operation). In either case, the automatic driving operations are realized by control performed by the control device 10. Alternatively, the control device 10 may perform appropriate driving operations by instructing the occupant, for example, of a target speed or a target trajectory, rather than automatically performing operations on behalf of the occupant.

[0018] The control device 10 is configured as a computer system having a CPU, ROM, RAM, etc., and is entirely mounted on the vehicle MV to be controlled. In other words, the control device 10 is configured as a so-called on-board ECU. Although the control device 10 in this embodiment is configured as a single device, it may also be configured as multiple devices that perform bidirectional communication with each other. Furthermore, some or all of the functions of the control device 10 described below may be realized by a server located at a location different from the vehicle MV.

[0019] 1 is a block diagram showing the configuration of the control device 10. The control device 10 includes, as block elements representing its functions, a memory unit 11, a route setting unit 12, a first plan creation unit 13, a second plan creation unit 14, a braking / driving force control unit 15, and a steering control unit 16.

[0020] The memory unit 11 is a non-volatile storage device provided in the control device 10, such as an SSD or HDD. The memory unit 11 stores various information necessary for the processing performed by the control device 10. This information includes the topography at each point on the road on which the vehicle MV may travel, specifically the gradient, curvature, number of lanes, width of each lane, etc. at each point. The information stored in the memory unit 11 may be updated as time passes, depending on the traveling position of the vehicle MV, etc.

[0021] The route setting unit 12 is a part that performs processing to set a route that the vehicle MV should travel to reach its destination. An operation unit 20, which is operated by the occupant, is provided in the cabin (not shown) of the vehicle MV, for example, as a touch panel. When the occupant operates the operation unit 20 to set a desired destination, the route setting unit 12 sets an appropriate route from the current location to the destination. It is preferable that the route setting unit 12 sets a route so that the energy required for traveling is minimized as much as possible. For example, it is preferable that a route that is as flat as possible or a route with the shortest distance is set. The route setting unit 12 and the operation unit 20 may be part of a navigation system installed in the vehicle MV.

[0022] The first plan creation unit 13 is a part that performs processing to create a trajectory plan. A "trajectory plan" is a plan that indicates the lateral position of the vehicle MV at each point when the vehicle MV travels along the route set by the route setting unit 12. The trajectory plan is created as the lateral position of the vehicle MV at each point every time the vehicle MV travels a predetermined distance along the route. As the "lateral position," for example, the distance from the center position of the road along the left-right direction to the center position of the vehicle along the same direction is used.

[0023] The first plan creation unit 13 creates a trajectory plan based on the route set by the route setting unit 12, topographical information such as curvature stored in the memory unit 11, and the traveling position of the vehicle MV. The traveling position of the vehicle MV can be acquired, for example, based on a signal from a GPS sensor mounted on the vehicle MV. The first plan creation unit 13 creates a trajectory plan so as to minimize the energy required for traveling. A specific method for creating a trajectory plan will be described later.

[0024] The second plan creation unit 14 is a part that performs processing to create a speed plan. A "speed plan" is a plan that indicates the traveling speed of the vehicle MV at each point when the vehicle MV travels along the route set by the route setting unit 12. The speed plan is created as the traveling speed at each time when a predetermined time has elapsed. As with the trajectory plan described above, the speed plan may also be created as the traveling speed at each point when the vehicle MV travels a predetermined distance along the route.

[0025] An occupant of the vehicle MV can input a desired set speed by operating the operation unit 20. The second plan creation unit 14 creates a speed plan so that the vehicle MV travels at the set speed or a traveling speed close to the set speed.

[0026] The second plan creation unit 14 creates a speed plan based on the above-mentioned set speed, as well as topographical information such as gradient and curvature stored in the memory unit 11, the trajectory plan created by the first plan creation unit, the current traveling position and traveling speed of the vehicle MV, etc. The current traveling position of the vehicle MV can be acquired, for example, based on a signal from a speed sensor mounted on the vehicle MV. The second plan creation unit 14 creates a speed plan so that the vehicle MV travels at a speed close to the set speed and so that the energy required for traveling is reduced. A specific method for creating a speed plan will be described later.

[0027] Braking / driving force control unit 15 is a unit that performs processing to cause vehicle MV to travel in accordance with the speed plan. Braking / driving force control unit 15 adjusts the braking force and driving force (hereinafter collectively referred to as "braking / driving force") of vehicle MV so that the traveling speed of vehicle MV at each time from the present onward matches the traveling speed indicated in the speed plan. Specifically, braking / driving force control unit 15 causes vehicle MV to travel while adjusting braking / driving force by performing feedback control so that the deviation between the traveling speed indicated in the speed plan and the actual traveling speed is reduced.

[0028] The braking / driving force control unit 15 performs the above feedback control based on the speed plan, the current traveling speed, and the current vehicle state. "Vehicle state" refers to various parameters used as state variables in control, such as the rotation speed and torque of a rotating electric machine equipped in the vehicle MV, and the position of the center of gravity of the vehicle MV. The braking / driving force control unit 15 acquires the vehicle state based on signals set in various parts of the vehicle MV and information obtained by estimation from these signals. The braking / driving force control unit 15 outputs braking / driving force command values ​​calculated as a result of the feedback control to various devices mounted on the vehicle MV. These devices include, for example, an inverter that adjusts the current supplied to the rotating electric machine, an electric brake device, and the like. The feedback control performed by the braking / driving force control unit 15 can employ various well-known methods, and therefore detailed description thereof will be omitted.

[0029] The steering control unit 16 is a part that performs processing to make the vehicle MV travel according to the trajectory plan. The steering control unit 16 steers the vehicle MV so that the lateral position of the vehicle MV at each point traveling along the route coincides with the lateral position indicated in the trajectory plan.

[0030] The steering control unit 16 calculates the required steering amount based on the speed plan and the trajectory plan, and calculates a yaw rate command value corresponding to the steering amount. The steering control unit 16 outputs the yaw rate command value to an electric steering device mounted on the vehicle MV, thereby realizing traveling according to the trajectory plan. As a specific method for calculating the steering amount and yaw rate command value according to the speed plan and the trajectory plan, for example, various well-known methods can be adopted, and therefore detailed explanations will be omitted. Note that the signal output from the steering control unit 16 to the vehicle MV may be a yaw rate command value as in this embodiment, or may be a command value that directly indicates the steering amount.

[0031] The braking / driving force control unit 15 and the steering control unit 16 as a whole can be said to be parts that make the vehicle MV travel in accordance with both the trajectory plan and the speed plan, and correspond to the "travel control unit" in this embodiment.

[0032] Furthermore, even if the control device 10 does not perform automatic operations on behalf of the occupant, but rather instructs the occupant on, for example, a target speed or target trajectory, the driving control unit still causes the vehicle MV to travel in accordance with both the trajectory plan and the speed plan (eventually).

[0033] An overview of the processing executed by the control device 10 will be described with reference to Fig. 2. The flowchart in Fig. 2 shows the order in which a trajectory plan is created by the first plan creation unit 13 and a speed plan is created by the second plan creation unit 14. As shown in the figure, a trajectory plan is created in the first step S01, and a speed plan is created in the subsequent step S02.

[0034] In this way, the control device 10 according to this embodiment is configured to first create only a trajectory plan and then create a velocity plan based on the existing trajectory plan, rather than simultaneously creating both a trajectory plan and a velocity plan as a result of solving one optimization problem. The advantages of creating each plan in this order will be explained later.

[0035] A method for creating a trajectory plan by the first plan creation unit 13 will now be described. FIG. 3 shows an example of a created trajectory plan. The line LL shown in the figure is a line indicating the boundary at the left end of the road (specifically, the lane) on which the vehicle MV travels. The line RL is a line indicating the boundary at the right end of the road on which the vehicle MV travels. In FIG. 3, the trajectory shown in the calculated trajectory plan, i.e., the trajectory along which the center position of the vehicle MV should pass, is indicated by an arrow TR.

[0036] In the example of FIG. 3, the road on which the vehicle MV is traveling begins with a curved road CV1 that curves to the right, followed by a curved road CV2 that curves to the left. As shown in FIG. 3, the vehicle MV traveling along the trajectory plan (arrow TR) enters the first curved road CV1 while changing its lateral position from the left side of the center of the road (i.e., the outside) to the right side. On the curved road CV1, the vehicle MV travels to the right side of the center of the road (i.e., the inside) and turns right along the road. The vehicle MV then exits the curved road CV1 while changing its lateral position from the right side of the center of the road to the left side again (i.e., the outside) and heads toward the next curved road CV2.

[0037] Next, the vehicle MV enters the curved road CV2 while changing its lateral position from the right side of the center of the road (i.e., the outside) to the left side. On the curved road CV2, the vehicle MV travels to the left side of the center of the road (i.e., the inside) and turns left along the road. The vehicle MV then exits the curved road CV2 while changing its lateral position from the left side of the center of the road to the right side (i.e., the outside) again.

[0038] As shown by the arrow TR in this example, the first plan creation unit 13 creates a trajectory plan so that the vehicle MV travels around each curve on the route along a so-called "out-in-out" trajectory. The trajectory shown by the arrow TR is a trajectory that allows the vehicle MV to travel without straying from the road, and can also be said to be a trajectory that minimizes the curvature at each point.

[0039] If an arbitrary trajectory of a vehicle MV along a route is divided into, for example, multiple sections each having a predetermined distance, the curvature of the trajectory in each section can be defined. By using the sum of the squares of the multiple curvatures calculated in this way as an evaluation function and selecting a trajectory that minimizes this evaluation function, a trajectory with minimum curvature can be obtained, as shown in the example indicated by the arrow TR. The first plan creation unit 13 of this embodiment uses, for example, this method to create a trajectory plan so that the vehicle MV travels around each curve along an out-in-out trajectory.

[0040] When the vehicle MV travels along such an out-in-out trajectory, the steering amount is relatively small, thereby reducing the energy required for steering. Furthermore, the energy required for traveling is further reduced due to factors such as a shorter travel distance of the vehicle MV and a smaller deceleration width due to a reduction in lateral acceleration. Simulations conducted by the inventors have confirmed that the energy consumed when the vehicle MV travels along an out-in-out trajectory is significantly reduced compared to when the vehicle MV travels along a trajectory in the center of the lane.

[0041] In this way, the trajectory plan created by the first plan creation unit 13 is based only on the route that the vehicle MV will travel from the current position onwards and topographical information (e.g., width and curvature) of the roads included in that route. In other words, the trajectory plan is created without using any information about the speed at which the vehicle MV will travel (i.e., speed plan) or vehicle specifications such as weight. Therefore, the computational load required to create the trajectory plan is relatively small.

[0042] In this embodiment, the first plan creation unit 13 creates a trajectory plan for a range from the current position of the vehicle MV to a position a predetermined distance ahead along the route. While the vehicle MV is traveling, the first plan creation unit 13 periodically creates and updates the trajectory plan as described above at each predetermined interval. The created trajectory plan is input from the first plan creation unit 13 to the second plan creation unit 14 and is used to create a speed plan.

[0043] In addition, if the destination and the entire route of the vehicle MV are determined in advance, a trajectory plan along the entire route may be created all at once before the vehicle MV starts traveling, and the above-described update may not be performed. For example, if the vehicle MV is a commercial vehicle or a route bus, such a trajectory plan can be generated in bulk. Furthermore, even if the vehicle MV is a general household vehicle, if the target values ​​and route of the vehicle MV are input, for example, the day before, such a trajectory plan can be generated in bulk.

[0044] The following describes how the second plan creation unit 14 creates a speed plan. As described above, the speed plan is created as a plan that indicates the traveling speed of the vehicle MV at each point when the vehicle MV travels along the route set by the route setting unit 12.

[0045] In the following, the number of divisions when the route that the vehicle MV will travel next is divided into divisions at fixed sampling distances will be represented as "S", and an index that takes an integer value between 0 and S will be represented as "k". Furthermore, if the target speed of the vehicle MV at a point that is the sampling distance × k away from the current location is represented as "v(k)", the speed plan can be represented as a set of v(k) for all values ​​of k. Note that v(0) included in the speed plan is the current traveling speed of the vehicle MV, and therefore its value is known.

[0046] The second plan creation unit 14 sets the individual values ​​of v(k) so that the value of the evaluation function shown in the following equation (1) is minimized, and creates a speed plan based on this.

number

[0047] "w" included in Eq. (1) f " and "w v " is a weighting coefficient. "F(k)" represents the braking / driving force at each point corresponding to the value of k. "v tgt " indicates a set speed that is preset by the user operating the operation unit 20.

[0048] If the vehicle MV is driven using its own vehicle weight due to the gradient to minimize the braking / driving force, the sum of squares of the braking / driving force F(k) (the first term in equation (1)) will be small, and the energy required for driving will be small. On the other hand, in this case, the fluctuation in the running speed of the vehicle MV will be large, and the difference between v(k+1) and v tgt The sum of the squares of the deviations from the set speed (the second term in equation (1)) becomes large. In this way, there is a trade-off between utilizing the vehicle's weight and maintaining the set speed. Minimizing the evaluation function in equation (1) means creating a speed plan that minimizes the energy consumed by braking / driving force while allowing for some speed fluctuations from the set speed, based on maintaining the set speed.

[0049] In order to solve the minimization problem of minimizing the evaluation function of equation (1), the constraint condition shown in equation (2) below is set.

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[0050] V in equation (2) max (k) represents the maximum travel speed allowed at each point corresponding to the value of k. max The value of (k) is calculated using a trajectory plan created in advance, and the method for doing so will be described later. The second plan creation unit 14 creates a velocity plan by solving a minimization problem that minimizes the evaluation function of equation (1) under the constraint of equation (2).

[0051] Since equation (1) includes F(k), which represents the braking / driving force, it is difficult to solve the above minimization problem as is. Therefore, the following transformation is applied to equation (1).

[0052] First, at each point corresponding to the value of k, the force of the forward direction component of the vehicle weight applied to the vehicle MV is calculated as "F grad (k)" and F grad (k) is expressed as the following equation (3).

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[0053] In equation (3), "g" is the acceleration due to gravity. "θ(k)" represents the gradient of the track at each point corresponding to the value of k. F grad Using (k), the equation of motion of the vehicle MV is expressed as the following equation (4).

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[0054] "F(t)" in equation (4) represents the braking / driving force as a function of time. t " represents the point index corresponding to time t among the k mentioned above. Note that F(t) and F grad (k t ) is the force applied to the vehicle MV normalized by the weight of the vehicle MV. Therefore, when using equation (4), it is not necessary to take into account the specific specifications of the vehicle MV.

[0055] The speed plan is created on the assumption that the traveling speed of the vehicle MV is adjusted to be close to the set speed. In this case, the fluctuation of the air resistance acting on the traveling vehicle MV can be considered to be approximately constant, so the effect of the air resistance is ignored in equation (4).

[0056] If the initial speed of the vehicle MV is "v0", the traveling speed of the vehicle MV at a point in time t after that is "v(t)", and the traveling distance of the vehicle MV up to that point is "s(t)", then from the above equation (4), the relationship between v(t) and s(t) can be expressed as the following equation (5).

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[0057] If the distance traveled by the vehicle MV before its traveling speed changes from v(k) to v(k+1) is Δs, the following equation (6) can be obtained from equation (5). Note that Δs is the "sampling distance" mentioned earlier.

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[0058] By modifying equation (6), the following equation (7) can be obtained.

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[0059] By substituting equation (7) into equation (1), we can obtain the following equation (8).

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[0060] Equation (8) is a transformation of the evaluation function of equation (1) into a form that does not include F(k). Equation (8) is in a form that includes only the decision variable v(k) as an unknown variable. This makes it possible to solve a minimization problem that minimizes the evaluation function of equation (8), and obtain v(k) as the speed plan. Equation (8) can be said to formulate the speed planning problem as an MPC (Model Predictive Control) problem described using Δs as the "sampling distance" and the entire distance range from 0 to S as the "horizon distance."

[0061] Here, the second term of equation (8) only needs to indicate the magnitude of the deviation between the traveling speed and the set speed. Therefore, the term shown in the following equation (9) may be used instead of the second term of equation (8).

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[0062] When the evaluation function of equation (8) is transformed as described above, the minimization problem can be reduced to a convex quadratic programming problem, which can be solved relatively easily using a general solver.

[0063] When solving the minimization problem, V included in the constraints of Eq. (2) max The value of (k) is calculated using the following equation (10).

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[0064] The "g" on the right side of equation (10) is the gravitational acceleration. lm " is the upper limit of the allowable lateral acceleration that the vehicle MV experiences while traveling on a curved road, and is set as a predetermined numerical value (fixed value) in units of gravitational acceleration. "κ(k)" represents the curvature of the trajectory on which the vehicle MV travels at each point corresponding to the value of k. The value of κ(k) at each point can be easily calculated based on a trajectory plan created in advance.

[0065] In this way, the V created based on the trajectory plan max By solving the minimization problem of minimizing equation (8) while incorporating (k) into the constraints, we can obtain the target speed v(k) at each point. In the following, we will refer to v(k) at each point that makes up the speed plan as "v ref (k)"

[0066] The speed plan created as above is the target speed v at each point for each sampling distance. refHowever, when using a speed plan for feedback control executed by braking / driving force control unit 15, it is preferable that the speed plan be expressed as a set of target speeds along a time series for each predetermined period. ref v instead of (k) ref It is preferable that the speed plan is expressed in the form of (t). ref (t) is converted by the method described below, and the final speed plan is v ref Create (t).

[0067] The vehicle MV is traveling at v ref (k) to v ref If the distance traveled by the vehicle MV before changing to (k+1) is Δs, the acceleration during the period in which the vehicle MV travels Δs can be approximately expressed as the following equation (11).

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[0068] Using equation (11), the traveling speed of the vehicle MV is v ref (k) to v ref v at each time until it changes to (k+1) ref (t) can be calculated using the following equation (12).

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[0069] In equation (12), "n" is an integer starting from 0 and is a variable that is counted up by 1 for each velocity feedback cycle. "Δt" represents the cycle.

[0070] In addition, as n counts up, "v ref If the time in the parentheses of "(k+1)" exceeds the range of the following equation (13), k in equation (12) is stepped up by 1, and n is reset to 0, and n is counted up again.

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[0071] The speed plan is created periodically using the method described above, and each time it is updated, it is updated so that the speed plan starts from the current position. The speed plan may be updated every time the vehicle MV travels a predetermined distance, or every time a predetermined time elapses. In either case, it is preferable that the frequency at which the second plan creation unit 14 updates the speed plan is higher than the frequency at which the first plan creation unit 13 updates the trajectory plan. Note that the "frequency at which the first plan creation unit 13 updates the trajectory plan" mentioned above also includes the "frequency" when the trajectory plan is created only once initially.

[0072] As described above, in the control device 10 of this embodiment, after the first plan creation unit 13 creates a trajectory plan, the second plan creation unit 14 creates a speed plan as a plan for driving the vehicle MV in accordance with the trajectory plan. In other words, the control device 10 does not simultaneously create both a trajectory plan and a speed plan by solving a complex optimization problem, but first creates only the trajectory plan independently of the speed plan. This reduces the computational load required to create the trajectory plan. Furthermore, since the speed plan is created on the assumption that the vehicle will drive in accordance with an existing trajectory plan, the computational load required to create the speed plan can also be reduced.

[0073] Although the effect of improving energy efficiency is smaller than when both the trajectory plan and the velocity plan are simultaneously created by the combined calculation, the required calculation load can be significantly reduced, which provides significant advantages, such as enabling the entire control device 10 to be configured as an on-board ECU.

[0074] The second plan creation unit 14 creates a speed plan on the assumption that the vehicle will travel in accordance with the existing trajectory plan. Specifically, the second plan creation unit 14 creates a speed plan based on the maximum speed V max(k) is calculated by using κ(k) obtained from the trajectory plan as in equation (10). The second plan creation unit 14 calculates V max By solving the optimization problem while using (k) as a constraint, the traveling speed of the vehicle MV at each point along the route can be determined to be the maximum speed V max (k) ref (k) or v ref Create a speed plan in the form (t).

[0075] When creating a speed plan, second plan creation unit 14 creates the speed plan using an equation of motion in which braking / driving forces are normalized by the weight of the vehicle MV, as in equation (4). By using this method, when creating a speed plan, the specifications of the vehicle MV are not required, as in the case of creating the previous trajectory plan. Note that, although specifications such as weight are required for final adjustment of braking / driving forces, in this embodiment, the processing requiring such specifications is handled by braking / driving force control unit 15 and steering control unit 16.

[0076] In other words, in this embodiment, the items to be formulated as an optimization problem are localized so that the braking / driving force control unit 15 and the like are responsible for processing that requires vehicle specifications, and the first plan creation unit 13 and the second plan creation unit 14 are responsible for highly abstract processing that does not require vehicle specifications. In other words, only those parts of the vehicle MV control algorithm that are difficult to describe manually are formulated as an optimization problem. This localization makes it possible to simplify the evaluation function (Equation (8)) and the constraints (Equation (2)), thereby reducing the computational load and the solution time.

[0077] In the control device 10 according to this embodiment, the creation of the trajectory plan and the creation of the velocity plan are separated, which simplifies the processes required for each plan creation, and as a result, a highly abstract formulation using the normalized equation of motion (Equation (4)) is possible. In other words, it can be said that the localization of the optimization problem as described above is achieved by separating the creation of the trajectory plan and the creation of the velocity plan.

[0078] The above-described method for creating a trajectory plan and a velocity plan reduces the required computational resources, reduces the size of the control device 10, and improves the mountability on the vehicle MV. However, as mentioned above, some or all of the control device 10 may be installed in a location different from the vehicle MV, and such an embodiment is also within the scope of the present disclosure.

[0079] The moving body to be controlled by the control device 10 may be a vehicle MV as in this embodiment, or may be a moving body of a different type than the vehicle MV.

[0080] The present embodiment has been described above with reference to specific examples. However, the present disclosure is not limited to these specific examples. Design modifications to these specific examples made by a person skilled in the art as appropriate are also included within the scope of the present disclosure as long as they comprise the features of the present disclosure. The elements of the above-described specific examples, as well as their arrangement, conditions, shape, etc., are not limited to those exemplified and can be modified as appropriate. The elements of the above-described specific examples can be combined in various ways as appropriate, as long as no technical contradictions arise.

[0081] The control device and control method described in the present disclosure may be implemented by one or more special-purpose computers configured by configuring a processor and memory programmed to perform one or more functions embodied in a computer program. The control device and control method described in the present disclosure may be implemented by a special-purpose computer configured by configuring a processor including one or more dedicated hardware logic circuits. The control device and control method described in the present disclosure may be implemented by one or more special-purpose computers configured by combining a processor and memory programmed to perform one or more functions with a processor including one or more hardware logic circuits. The computer program may be stored as instructions executed by a computer on a computer-readable non-transitory storage medium. The dedicated hardware logic circuit and the hardware logic circuit may be implemented by a digital circuit including multiple logic circuits or an analog circuit. [Explanation of symbols]

[0082] MV: Vehicle 10: Control device 13: First Planning Department 14: Second Planning Department 15: Braking / driving force control unit 16: Steering control unit

Claims

1. A control device (10) for a moving body (MV), a first plan creation unit (13) that creates a trajectory plan, which is a plan indicating the lateral position of a moving body at each point when the moving body travels along a predetermined route; a second plan creation unit (14) that creates a speed plan, which is a plan indicating the traveling speed of the mobile body at each point when the mobile body travels along the route; a travel control unit (15, 16) that causes the moving body to travel in accordance with both the trajectory plan and the speed plan, The second plan creation unit After the first plan creation unit creates the trajectory plan, the first plan creation unit creates the velocity plan as a plan for causing a moving body to travel in accordance with the trajectory plan; A control device, wherein the second plan creation unit updates the velocity plan more frequently than the first plan creation unit updates the trajectory plan.

2. The second plan creation unit Using the trajectory plan, calculate a maximum allowable speed at each point along the route; The control device according to claim 1 , wherein the speed plan is created so that the traveling speed of the mobile object at each point along the route does not exceed the maximum speed.

3. 3. The control device according to claim 1, wherein the travel control unit causes the mobile object to travel while performing feedback control so as to reduce a deviation between the travel speed indicated in the speed plan and an actual travel speed.

4. The control device according to claim 1 , wherein the first plan creation unit creates the trajectory plan so that the moving object travels on a curved road along an out-in-out trajectory.

5. A control device (10) for a moving body (MV), a first plan creation unit (13) that creates a trajectory plan, which is a plan indicating the lateral position of a moving body at each point when the moving body travels along a predetermined route; a second plan creation unit (14) that creates a speed plan, which is a plan indicating the traveling speed of the mobile body at each point when the mobile body travels along the route; a travel control unit (15, 16) that causes the moving body to travel in accordance with both the trajectory plan and the speed plan, The second plan creation unit After the first plan creation unit creates the trajectory plan, the first plan creation unit creates the velocity plan as a plan for causing a moving body to travel in accordance with the trajectory plan; The second plan creation unit creates the speed plan using an equation of motion in which braking / driving forces are normalized by the weight of the moving body.

6. A program for a control device (10) of a moving body (MV), a first planning process for creating a trajectory plan, which is a plan indicating a lateral position of the moving body at each point when the moving body travels along a predetermined route; a second plan creation process for creating a speed plan, which is a plan indicating a traveling speed of the mobile object at each point when the mobile object travels along the route; a travel control process for causing the moving body to travel in accordance with both the trajectory plan and the velocity plan, The second plan creation process includes: a process of creating the velocity plan as a plan for traveling a moving object according to the trajectory plan after creating the trajectory plan as the first plan creation process, The update frequency of the velocity plan is higher than the update frequency of the trajectory plan.

7. A program for a control device (10) of a moving body (MV), a first planning process for creating a trajectory plan, which is a plan indicating a lateral position of the moving body at each point when the moving body travels along a predetermined route; a second plan creation process for creating a speed plan, which is a plan indicating a traveling speed of the mobile object at each point when the mobile object travels along the route; a travel control process for causing the moving body to travel in accordance with both the trajectory plan and the velocity plan, The second plan creation process includes: a process of creating the velocity plan as a plan for traveling a moving object according to the trajectory plan after creating the trajectory plan as the first plan creation process, The second plan creation process is a process of creating the speed plan using an equation of motion in which braking / driving forces are normalized by the weight of the moving body.

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