Method, device and medium for determining economic torque in high-speed road ramp scenario

Abstract

The present invention relates to a method, device and medium for determining economic torque in a highway ramp scenario, belonging to the field of vehicle control technology, the method comprising: merging ramp slices based on the road type corresponding to the ramp slices to determine the merged fusion ramp; the ramp slices are obtained by slicing the road in front of the vehicle; based on the slope and slope length of the fusion ramp, the acceleration of the vehicle is determined; based on the acceleration, the economic torque is determined. The method for determining economic torque in a highway ramp scenario provided by the present invention accurately identifies a complete fusion ramp in a complex ramp environment, and calculates the acceleration of the vehicle under the fusion ramp condition based on the slope and slope length of the fusion ramp, and then calculates the required economic torque based on the acceleration and the vehicle dynamics equation. The economic torque is the torque required for the vehicle to maintain optimal fuel economy on the ramp, which can not only meet driving needs, but also improve fuel saving rate.

Description

Technical Field

[0001] The present invention relates to the field of vehicle control technology, and in particular to a method, device and medium for determining economic torque in a highway ramp scenario. Background Art

[0002] Vehicle fuel saving rate is an important indicator used to measure the extent to which a vehicle can save fuel during operation. Different types of vehicles and different technical routes can achieve different degrees of fuel saving effects.

[0003] The existing method proposes a ramp cruise speed control method based on high-precision maps. By setting the speed adjustment distance that triggers the speed adjustment, when the vehicle reaches the speed adjustment distance, the vehicle speed is controlled based on the speed adjustment threshold and the speed adjustment slope through a table lookup method, which can maximize the fuel saving rate. However, this method plans the economical cruise speed on the slope based on the information provided by the high-precision map, and the distance of the road ahead information that the high-precision map can provide is not long enough, and comprehensive planning cannot be performed in complex slope environments such as large slope changes and super long slopes. Summary of the invention

[0004] In view of this, it is necessary to provide a method, device and medium for determining the economic torque in a highway ramp scenario, so as to plan the economic torque of the vehicle in a complex ramp environment.

[0005] In order to achieve the above object, the present invention provides a method for determining economic torque in a highway ramp scenario, comprising:

[0006] Merging the ramp slices based on the road types corresponding to the ramp slices to determine a merged fused ramp; the ramp slices are obtained by slicing the road in front of the vehicle;

[0007] Determining the acceleration of the vehicle based on the slope and the length of the blended ramp;

[0008] Based on the acceleration, an economic torque is determined.

[0009] In a possible implementation, merging the ramp slices based on the road types corresponding to the ramp slices to determine the merged fused ramp includes:

[0010] Traversing the ramp slices, when determining that the road type of the current ramp slice is an uphill type, determining the sequence number of the current ramp slice as the starting sequence number;

[0011] Traversing the ramp slices based on the starting sequence number, and when determining that the road type of the next ramp slice is an uphill type, merging the next ramp slice with the current ramp slice, and determining the sequence number of the next ramp slice as the end sequence number;

[0012] When the road type of the next ramp slice is a downhill type or a flat road type, the traversal is stopped and the merged fused ramp is obtained.

[0013] In a possible implementation manner, before determining the acceleration of the vehicle based on the slope and the slope length of the fused ramp, the method further includes:

[0014] Based on the starting sequence number and the ending sequence number, the slope and the slope length of the fusion ramp are determined.

[0015] In a possible implementation, determining the acceleration of the vehicle based on the slope and the slope length of the fused ramp includes:

[0016] Divide the preset slope into sections to obtain multiple slope values;

[0017] Divide the preset slope length into sections to obtain multiple slope length values;

[0018] Each slope value is matched with a different slope length value, and the corresponding acceleration value is determined by a simulation model; the simulation model is a vehicle dynamics model built based on trucksim and matlab;

[0019] Constructing an acceleration table based on the corresponding relationship between the slope value, the slope length value and the acceleration value;

[0020] Based on the gradient and the length of the blended ramp, the acceleration of the vehicle is determined in the acceleration table.

[0021] In a possible implementation, determining the economic torque based on the acceleration includes:

[0022] determining an acceleration resistance based on the acceleration;

[0023] determining a driving force based on the rolling resistance, air resistance, slope resistance and the acceleration resistance of the vehicle;

[0024] Based on the driving force, the economic torque is determined.

[0025] In a possible implementation, the expression of the economic torque is as follows:

[0026]

[0027] in, T represents economic torque, Indicates driving force, represents the wheel radius, Indicates the gear ratio. Indicates the transmission ratio of the final reducer. Indicates transmission efficiency.

[0028] The present invention also provides an economic torque determination device in a high-speed road ramp scenario, comprising:

[0029] A merging module, configured to merge the ramp slices based on the road types corresponding to the ramp slices, and determine a merged fused ramp; the ramp slices are obtained by slicing the road in front of the vehicle;

[0030] A first determination module, configured to determine the acceleration of the vehicle based on the slope and the slope length of the fused ramp;

[0031] The second determination module is configured to determine an economic torque based on the acceleration.

[0032] On the other hand, the present invention also provides an electronic device, including a memory and a processor, wherein:

[0033] The memory is used to store programs;

[0034] The processor is coupled to the memory and is used to execute the program stored in the memory to implement the method for determining the economic torque in the highway ramp scenario described in any of the above implementations.

[0035] On the other hand, the present invention further provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the method for determining the economic torque in the highway ramp scenario described in any of the above-mentioned implementation methods is implemented.

[0036] On the other hand, the present invention also provides a computer program product, including a computer program, which, when executed by a processor, implements the method for determining economic torque in a highway ramp scenario described in any of the above implementations.

[0037] The beneficial effects of the present invention are as follows: the method, device and medium for determining economic torque in a highway ramp scenario provided by the present invention can obtain ramp slices by slicing the road in front of the vehicle, and merge the ramp slices according to the road type corresponding to the ramp slices, so as to obtain a continuous and complete fused ramp, thereby realizing accurate identification of the complete fused ramp in a complex ramp environment, and calculating the acceleration of the vehicle under the fused ramp condition according to the slope and slope length of the fused ramp, and then calculating the required economic torque based on the acceleration and vehicle dynamics equations. The economic torque is the torque required for the vehicle to maintain optimal fuel economy on the ramp, which can not only meet driving needs, but also improve fuel saving rate, so that the autonomous driving vehicle can accurately respond to complex ramp conditions on the highway to optimize the performance and fuel economy of the vehicle, which not only improves driving efficiency, but also helps to achieve a more environmentally friendly driving experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0039] Figure 1 One of the method flow charts of an embodiment of the method for determining economic torque in a highway ramp scenario provided by the present invention;

[0040] Figure 2 A schematic diagram of ramp slice merging provided by the present invention;

[0041] Figure 3 A schematic diagram of the joint simulation provided by the present invention;

[0042] Figure 4 A second method flow chart of an embodiment of a method for determining economic torque in a highway ramp scenario provided by the present invention;

[0043] Figure 5 A schematic structural diagram of an embodiment of a device for determining economic torque in a highway ramp scenario provided by the present invention;

[0044] Figure 6 A schematic structural diagram of an embodiment of an electronic device provided by the present invention. DETAILED DESCRIPTION

[0045] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0046] In the description of the embodiments of the present invention, unless otherwise specified, "multiple" means two or more than two. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" may mean: A exists alone, A and B exist at the same time, and B exists alone.

[0047] The descriptions of "first", "second", etc. involved in the embodiments of the present invention are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the technical features defined as "first" or "second" may explicitly or implicitly include at least one of the features.

[0048] Figure 1 This is a method flow chart of an embodiment of a method for determining economic torque in a highway ramp scenario provided by the present invention, as shown in FIG. Figure 1 As shown, the method for determining the economic torque in the highway ramp scenario includes:

[0049] S101, merging the ramp slices based on the road types corresponding to the ramp slices to determine a merged fused ramp; the ramp slices are obtained by slicing the road in front of the vehicle;

[0050] S102, determining the acceleration of the vehicle based on the slope and the slope length of the integrated ramp;

[0051] S103: Determine economic torque based on the acceleration.

[0052] It should be noted that: based on the road map information in front of the vehicle provided by Tbox, the road in front of the vehicle can be sliced ​​to obtain several ramp slices, each of which represents a section of the road with a certain slope and length. The road type of the ramp slice can be determined based on the slope of the ramp slice, and the road type can include uphill type, downhill type and flat road type.

[0053] Compared with the prior art, the method for determining economic torque in a highway ramp scenario provided by an embodiment of the present invention obtains ramp slices by slicing the road in front of the vehicle, and merges the ramp slices according to the road type corresponding to the ramp slices, so as to obtain a continuous and complete fused ramp, thereby realizing accurate identification of the complete fused ramp in a complex ramp environment, and calculating the acceleration of the vehicle under the fused ramp condition according to the slope and slope length of the fused ramp, and then calculating the required economic torque based on the acceleration and vehicle dynamics equations. The economic torque is the torque required for the vehicle to maintain optimal fuel economy on the ramp, which not only meets driving needs, but also improves fuel saving rate, so that the autonomous driving vehicle can accurately respond to complex ramp conditions on the highway to optimize the performance and fuel economy of the vehicle, which not only improves driving efficiency, but also helps to achieve a more environmentally friendly driving experience.

[0054] In some embodiments of the present invention, merging the ramp slices based on the road types corresponding to the ramp slices to determine the merged fused ramp includes:

[0055] Traversing the ramp slices, when determining that the road type of the current ramp slice is an uphill type, determining the sequence number of the current ramp slice as the starting sequence number;

[0056] Traversing the ramp slices based on the starting sequence number, and when determining that the road type of the next ramp slice is an uphill type, merging the next ramp slice with the current ramp slice, and determining the sequence number of the next ramp slice as the end sequence number;

[0057] When the road type of the next ramp slice is a downhill type or a flat road type, the traversal is stopped and the merged fused ramp is obtained.

[0058] For example, the slope node data can be initialized and classified according to the road map information ahead provided by Tbox, and sliced ​​and preliminarily fused according to the differences and similarities of the ramp types.

[0059] Traverse all ramp slices of the road ahead and identify the road type of each ramp slice:

[0060] If the road type of the current ramp slice is an invalid type, an error is returned and an error message is output to the console;

[0061] If the road type of the current ramp slice is a flat road type or a downhill type, skip and continue to judge the next one;

[0062] If the road type of the current ramp slice is an uphill type, record the sequence number of the current slice as the starting sequence number, and continue to traverse backwards from the starting sequence number to identify the road type of each slice:

[0063] If the road type of the next ramp slice is not a downhill type or a flat road type, the next ramp slice is added to the previous ramp slice, and the end sequence number is updated to the sequence number of the next ramp slice;

[0064] If the road type of the next ramp slice is a flat road type and a downhill type, the traversal ends.

[0065] Thus, one or several continuous road slices can be obtained, which can be regarded as a complete uphill slope or a fused ramp. Figure 2 The schematic diagram of ramp slice merging provided by the present invention is as follows: Figure 2 As shown. And the initial sequence number, the end sequence number and the total length of the ramp are known.

[0066] In some embodiments of the present invention, before determining the acceleration of the vehicle based on the slope and the slope length of the fused ramp, the method further includes:

[0067] Based on the starting sequence number and the ending sequence number, the slope and the slope length of the fusion ramp are determined.

[0068] The fused ramp is composed of one or several continuous road slices. According to the initial sequence number and the end sequence number of the road slice, the slope length corresponding to each road slice is accumulated to obtain the slope length of the fused ramp.

[0069] The slope of the fusion ramp is determined according to the initial sequence number and the end sequence number of the fusion ramp. The calculation process is as follows:

[0070] If the initial sequence number is zero and the initial sequence number is equal to the end sequence number, that is, the current fused ramp consists of a single slice and is the first segment, indicating that the vehicle is going uphill. At this time, the slope of the fused ramp is the slope of the current slice.

[0071] If the initial sequence number is zero and the initial sequence number is not equal to the end sequence number, that is, the current fused ramp consists of multiple slices and starts from the first section, which means that the vehicle is going uphill. At this time, the slope of the fused ramp is the weighted average slope of all slices (calculated and accumulated for each slice in the fused ramp: single slice slope * single slice slope length / total ramp length).

[0072] If the initial sequence number is not zero and the initial sequence number is equal to the end sequence number, that is, the current fused ramp consists of a single slice and is not the first segment, indicating that the fused ramp is in front of the vehicle. At this time, the slope of the fused ramp is the slope of the current slice, and the distance between the vehicle and the fused ramp is the sum of the lengths of all slices before the initial slice.

[0073] If the initial sequence number is not zero and the initial sequence number is not equal to the end sequence number, that is, the current merging ramp consists of multiple slices and does not start from the first segment, it means that the merging ramp is in front of the vehicle. At this time, the slope of the merging ramp is the weighted average slope of all slices (calculated and accumulated for each slice in the merging ramp: single slice slope * single slice slope length / total ramp length), and the distance between the vehicle and the merging ramp is the sum of the lengths of all slices before the initial slice.

[0074] The method for determining economic torque in a highway ramp scenario provided by an embodiment of the present invention designs a ramp fusion method based on ramp slicing, which can correctly identify the complete ramp and perform smoothing to facilitate calculation.

[0075] In some embodiments of the present invention, determining the acceleration of the vehicle based on the slope and the slope length of the fused ramp includes:

[0076] Divide the preset slope into sections to obtain multiple slope values;

[0077] Divide the preset slope length into sections to obtain multiple slope length values;

[0078] Each slope value is matched with a different slope length value, and the corresponding acceleration value is determined by a simulation model; the simulation model is a vehicle dynamics model built based on trucksim and matlab;

[0079] Constructing an acceleration table based on the corresponding relationship between the slope value, the slope length value and the acceleration value;

[0080] Based on the gradient and the length of the blended ramp, the acceleration of the vehicle is determined in the acceleration table.

[0081] In the embodiment of the present invention, a dynamic model of the vehicle, i.e., a simulation model, can be pre-built according to trucksim and matlab. The simulation model can simulate the scenarios of the vehicle under various working conditions. Figure 3 A schematic diagram of the joint simulation process of the simulation model provided by the present invention.

[0082] The simulation model provided by the embodiment of the present invention includes two parts:

[0083] The first is the controlled object model. In order to accurately simulate the real dynamics of the vehicle and accurately calculate the vehicle's fuel consumption, the controlled object model of the algorithm is built in TruckSim using the detailed data of the vehicle.

[0084] The second is to construct a mathematical model of the vehicle driving process based on vehicle dynamics in order to derive the subsequent control law. The controller model is constructed in Simulink.

[0085] In addition, the selection of the hill bottom speed is based on the recommended speed in the regulatory requirements, and is combined with the speed range of the vehicle under the current operating conditions that enables its engine to operate in the economic speed range. The final economic cruising speed is used as the hill bottom speed.

[0086] The top speed is classified into two cases: if there is no need to shift gears, the top speed should be set to the vehicle's minimum speed without shifting gears, that is, the vehicle's minimum speed in the current gear. If the vehicle must downshift, the top speed is set to the shift point speed corresponding to the vehicle's final gear.

[0087] After determining the economical speeds at the bottom and top of the slope, the slope length and slope of the integrated ramp are obtained in the above embodiment, and the corresponding acceleration value can be calculated through the simulation model.

[0088] However, in actual use, it is obviously unrealistic to call the model for calculation every time. Therefore, the solution of this method is as follows:

[0089] Create a discrete data table, divide the preset slope into 6 sections {1, 2, 3, 4, 5, 6}, and get 6 slope values. Divide the preset slope length into 15 sections {200, 400, 600, 800, 1000, 1200, 1400, 1600, 1800, 2000, 2200, 2400, 2600, 2800, 3000}, and get 15 slope length values.

[0090] Each slope value is matched with a different slope length value, that is, there are 6*15 groups of corresponding data in total. The simulation model is used to calculate the acceleration values ​​corresponding to 6*15 situations, so as to construct an acceleration table based on the correspondence between the slope value, slope length value and acceleration value.

[0091] For example, a suitable slope length gear and slope gradient gear may be selected according to the slope gradient and slope length of the merging slope.

[0092] Since the actual slope length is not exactly equal to the designated slope lengths, it is necessary to select the appropriate gear based on the actual slope length. The strategy is to use the smallest deceleration value possible to avoid the vehicle from slowing down too quickly. If the slope length is less than 200, directly set it to 200 gear; if the slope length is greater than 3000, directly set it to 3000 gear; if it is between two gears, use the smaller gear.

[0093] Similar to the slope length, the slope is not always exactly an integer value, so it also needs to be processed. If the slope is greater than 0 and less than 1, select the gear with a slope of 1, and multiply the corresponding deceleration by the slope value, and then multiply by a proportional coefficient to ensure smooth transition of small slopes; if the slope is greater than 6%, select the gear of 6; if the slope value is between two gears, select the smaller gear.

[0094] Therefore, according to the slope and length of the fusion ramp, the corresponding acceleration value can be obtained by looking up the table.

[0095] The method for determining the economic torque in a highway ramp scenario provided by an embodiment of the present invention can better simulate the dynamic characteristics of the research object by using a simulation model built using vehicle information of a heavy truck, and proposes a method for determining uphill acceleration. The acceleration data calculated by the simulation model is simplified into a table, and the corresponding economic acceleration can be obtained by querying the table in a prescribed manner.

[0096] In some embodiments of the present invention, determining the economic torque based on the acceleration includes:

[0097] determining an acceleration resistance based on the acceleration;

[0098] determining a driving force based on the rolling resistance, air resistance, slope resistance and the acceleration resistance of the vehicle;

[0099] Based on the driving force, the economic torque is determined.

[0100] In some embodiments of the present invention, the expression of the economic torque is as follows:

[0101]

[0102] in, T represents economic torque, Indicates driving force, represents the wheel radius, Indicates the gear ratio. Indicates the transmission ratio of the final reducer. Indicates transmission efficiency.

[0103] After the acceleration is determined, the acceleration resistance can be calculated based on the product of the acceleration and the vehicle mass.

[0104] When the wheel rolls, when the elastic tire rolls on the hard road, the tire deforms and the internal friction produces elastic hysteresis loss, thus forming rolling resistance. The calculation formula of the vehicle's rolling resistance Ff is: Ff=vehicle mass*g*vehicle resistance coefficient.

[0105] The component of the air force received by a car when it is traveling in a straight line in the direction of travel is the air resistance, which is proportional to the dynamic pressure of the relative velocity of the airflow. The specific calculation formula for the air resistance Fw is: Fw=air resistance coefficient*air density*windward area*square of the relative air velocity / 2.

[0106] Ramp resistance is the separation of the vehicle's gravity along the ramp when the vehicle is driving uphill. Due to my country's highway regulations, the maximum longitudinal slope does not exceed 6% even in mountainous and hilly areas, so the slope of general roads is relatively small, so the sine value of the ramp angle is approximately the tangent value, that is, the slope value. The specific calculation formula for the ramp resistance Fi is: Fi = vehicle mass * g * slope.

[0107] According to the vehicle dynamics equation, the driving force is equal to the sum of rolling resistance, air resistance, and slope resistance minus acceleration resistance, that is, the calculation formula for the driving force Ft is as follows: Ft=Ff+Fw+Fi–(vehicle mass*acceleration).

[0108] Furthermore, the calculation method of the economic torque T is: T=Ft*wheel radius / (transmission ratio of the gear*transmission ratio of the final reducer*transmission efficiency).

[0109] That is, the expression of economic torque T is as follows:

[0110]

[0111] in, Trepresents economic torque, Indicates driving force, represents the wheel radius, Indicates the gear ratio. Indicates the transmission ratio of the final reducer. Indicates transmission efficiency.

[0112] Since the actual situation is generally more complicated than the theoretical calculation, the torque can be increased by 5% as backup power.

[0113] The method for determining the economic torque in a highway ramp scenario provided by an embodiment of the present invention combines the current vehicle speed, target vehicle speed, slope and slope length of the ramp ahead of the vehicle in the highway ramp scenario, obtains the corresponding deceleration through a simulation model, and finally calculates the final economic torque according to the vehicle dynamics equation, thereby achieving the effect of improving the fuel saving rate.

[0114] Figure 4 The second method flow chart of an embodiment of the method for determining the economic torque in a highway ramp scenario provided by the present invention is as follows: Figure 4 As shown, the method for determining the economic torque in the highway ramp scenario includes:

[0115] S401, ramp slice classification.

[0116] Based on the road map information provided by Tbox, the slope node data is initialized and classified to determine the slope type. Then the ramp nodes are traversed and sliced ​​and initially merged according to the differences and similarities of the ramp types.

[0117] According to my country's highway route design specifications, the maximum longitudinal slope of expressways in plain and slightly hilly areas is 3%, and that in mountainous and heavily hilly areas is 5%; the maximum slope of first-class automobile-only highways in plain and slightly hilly areas is 4%, and that in mountainous and heavily hilly areas is 6%. It can be seen that the slope of general roads will not exceed 6%. Therefore, the following division method is adopted:

[0118] (1) Ramp type is invalid (default value, used for validity check)

[0119] (2) 0%<= slope<0.2%: flat road;

[0120] (3) 0.2%<=slope<1%: uphill, the slope is considered to be 1%;

[0121] (4) 1%<=slope<2%: uphill, the slope is considered to be 2%;

[0122] (5) 2%<=slope<3%: uphill, the slope is considered to be 3%;

[0123] (6) 3%<=slope<4%: uphill, the slope is considered to be 4%;

[0124] (7) 4%<= slope<5%: uphill, the slope is considered to be 5%;

[0125] (8) 5%<=slope<6%: uphill, the slope is considered to be 6%;

[0126] (9) Slope <0%: uphill, the slope is considered to be 5%;

[0127] S402, ramp slices are merged.

[0128] Based on the ramp slice of the slope of the road ahead, the information of the next ramp is obtained according to the road type of the slice. Then, the end point of this ramp is found with the slice as the starting point. Finally, the entire slice is merged into a complete ramp for subsequent processing.

[0129] S402.1. Find the starting slice of the first ramp ahead.

[0130] The upper layer initializes and classifies the slope node data based on the map information of the road ahead provided by tbox, slices and initially fuses the data according to the similarities and differences of the ramp types, and outputs it to this layer. Traverse the ramp slices of the road ahead and identify the road type of each slice: if it is an invalid type, return an error and output the error message to the console; if it is a flat road type or a downhill type, skip and continue to judge the next one; if it is an uphill type, record the current slice number as the starting slice number and enter S402.2.

[0131] S402.2. Find the end slice of the first ramp ahead.

[0132] Traverse backwards from the starting slice number recorded in step S402.1. If the current slice type is not a downhill type or a flat road type, add the current slope length to the merged slice and update the ending slice number to the current slice number. If the current slice type is a flat road type or a downhill type, end the traversal. From this, one or more consecutive road slices are obtained, which are regarded as a complete uphill slope, and the initial slice number, the ending slice number, and the total length of the uphill slope are known.

[0133] S403: Extract the first ramp information: Calculate the ramp gradient and the distance from the first ramp.

[0134] If the initial slice number is zero and the initial slice number is equal to the ending slice number, that is, the current ramp consists of a single slice and is the first section, indicating that the vehicle is going uphill, and the slope of the ramp is the slope of the current slice.

[0135] If the initial slice number is zero and the initial slice number is not equal to the ending slice number, that is, the current ramp consists of multiple slices and starts from the first section, it means that the vehicle is going uphill. At this time, the slope of the ramp is the weighted average slope of all slices (calculated and accumulated for each slice in the ramp: single slice slope * single slice slope length / total length of the ramp).

[0136] If the initial slice number is not zero and the initial slice number is equal to the ending slice number, that is, the current ramp consists of a single slice and is not the first segment, indicating that the ramp is in front of the vehicle. At this time, the slope of the ramp is the slope of the current slice, and the distance from the ramp is the sum of the lengths of all slices before the initial slice.

[0137] If the initial slice number is not zero, and the initial slice number is not equal to the ending slice number, that is, the current ramp consists of multiple slices and does not start from the first section, which means that the ramp is in front of the vehicle. At this time, the slope of the ramp is the weighted average slope of all slices (calculated and accumulated for each slice in the ramp: single slice slope * single slice slope length / total ramp length), and the distance from the ramp is the sum of the lengths of all slices before the initial slice.

[0138] S404. Calculate economic acceleration.

[0139] S404.1. Construct a simulation model to simulate the driving of the target vehicle under various working conditions. The simulation model is divided into two parts.

[0140] According to the obtained fused ramp information, combined with the simulation model (through trucksim and matlab joint simulation, using trucksim to build the controlled object model of the heavy truck, and building the cruise controller model in simlink, which can better simulate uphill and downhill conditions), the corresponding vehicle deceleration is determined.

[0141] S404.2. Confirm the speed at the bottom and top of the slope.

[0142] The selection of the hill bottom speed is based on the recommended speed in regulatory requirements, and is combined with the speed range of the vehicle under the current operating conditions that enables its engine to operate in the economic speed range. The final economic cruising speed is used as the hill bottom speed.

[0143] The top speed of the slope needs to be discussed in different situations. If there is no need to shift gears, the top speed of the slope should be set to the minimum speed of the vehicle without shifting gears, that is, the minimum speed of the vehicle in the current gear. If the vehicle must downshift, the top speed of the slope is set to the shift point speed corresponding to the final gear of the vehicle.

[0144] S404.3. Acceleration confirmation.

[0145] After determining the economical speeds at the bottom and top of the slope, the corresponding acceleration value can be calculated by the model in combination with the slope length and slope data obtained in S403. However, in actual use, it is obviously unrealistic to call the model for calculation every time. The solution of this method is as follows:

[0146] S404.3.1. Create a discrete data table, divide the slope into 6 sections {1, 2, 3, 4, 5, 6}, and divide the slope length into 15 sections {200, 400, 600, 800, 1000, 1200, 1400, 1600, 1800, 2000, 2200, 2400,2600, 2800, 3000}. Use the model to obtain the values ​​corresponding to 6*15 cases and establish a deceleration table.

[0147] S404.3.2. Select the appropriate gear for the slope length. Since the actual slope length is often not exactly equal to the designated slope lengths, it is necessary to select the appropriate gear based on the actual slope length. The strategy is to use the smallest deceleration value possible to avoid the vehicle from slowing down too quickly. If the slope length is less than 200, directly set it to 200 gear; if the slope length is greater than 3000, directly set it to 3000 gear; if it is between two gears, use the smaller gear.

[0148] S404.3.3. Select the appropriate gear for the slope. Similar to the slope length, the slope is not always an integer, so it also needs to be processed. If the slope is greater than 0 and less than 1, select the gear with a slope of 1, and multiply the corresponding deceleration by the slope value, and then multiply by a proportional coefficient to ensure smooth transition of small slopes; if the slope is greater than 6%, select the gear of 6; if the slope value is between two gears, select the smaller gear.

[0149] S404.3.4. Look up the table to obtain the corresponding acceleration value.

[0150] S405: Calculate economic torque.

[0151] According to the vehicle dynamics equation, the rolling resistance, air resistance and slope resistance of the vehicle are calculated to obtain the driving force of the vehicle, thereby obtaining the optimal economic torque on the slope.

[0152] S405.1. Calculate vehicle resistance.

[0153] S405.1.1. Calculate the rolling resistance of the vehicle. When the wheels roll, the elastic tires roll on the hard road, the tires deform, and the internal friction produces elastic hysteresis loss, thus forming rolling resistance. The specific calculation formula is: Ff = vehicle mass * g * vehicle resistance coefficient.

[0154] S405.1.2. Calculate the air resistance of the vehicle. The component of the air force in the direction of travel received by the vehicle when it is traveling in a straight line is the air resistance, which is proportional to the relative velocity and dynamic pressure of the airflow. The specific calculation formula is: Fw = air resistance coefficient * air density * windward area * square of the relative velocity of the air / 2.

[0155] S405.1.3. Calculate the slope resistance of the vehicle. The slope resistance is the separation of the vehicle's gravity along the slope when the vehicle is driving uphill. Due to my country's highway regulations, the maximum longitudinal slope does not exceed 6% even in mountainous and hilly areas, so the slope of general roads is relatively small, so the sine value of the ramp angle is approximately the tangent value, that is, the slope value. The specific calculation formula is: Fi = vehicle mass * g * slope.

[0156] S405.2. Calculate the economic torque.

[0157] S405.2.1. According to the vehicle dynamics equation, the driving force is equal to the sum of rolling resistance, air resistance, and slope resistance minus acceleration resistance, that is: Ft = Ff + Fw + Fi – (vehicle mass * acceleration).

[0158] S405.2.2. Calculate the torque: T = Ft * wheel radius / (gear ratio of the gear * final reducer gear ratio * transmission efficiency).

[0159] S405.2.3. Since the actual situation is generally more complicated than the theoretical calculation, the torque can be increased by 5% as a backup power.

[0160] The autonomous vehicle classifies the received ramp slices, merges them according to their types, and extracts the information of the first ramp. Then, it calculates the economic deceleration based on the simulation model, and finally calculates the economic torque based on the vehicle dynamics equation and outputs it to the control layer.

[0161] The economic torque determination method provided by the present invention has the following advantages:

[0162] (1) The information provided by Tbox is used to plan the economic torque on the slope, which can obtain the road information 3 km ahead and make the planning more comprehensive;

[0163] (2) The simulation model built using heavy truck vehicle information can better simulate the dynamic characteristics of the research object;

[0164] (3) A ramp fusion method based on ramp slices is designed, which can correctly identify the complete ramp and perform smoothing to facilitate calculation;

[0165] (4) A method for determining uphill deceleration was designed. The deceleration data calculated by the simulation model was simplified into a table. The corresponding economic deceleration can be obtained by querying the table in a prescribed way.

[0166] In order to better implement the method for determining the economic torque in a highway ramp scenario in an embodiment of the present invention, based on the method for determining the economic torque in a highway ramp scenario, an embodiment of the present invention further provides a device for determining the economic torque in a highway ramp scenario. Figure 5 FIG. 1 is a schematic diagram of a structure of an embodiment of a device for determining economic torque in a highway ramp scenario provided by the present invention. Figure 5 As shown, the economic torque determination device 500 in the highway ramp scenario includes:

[0167] A merging module 510 is used to merge the ramp slices based on the road types corresponding to the ramp slices to determine a merged fused ramp; the ramp slices are obtained by slicing the road in front of the vehicle;

[0168] A first determination module 520, configured to determine the acceleration of the vehicle based on the slope and the length of the fused ramp;

[0169] The second determination module 530 is configured to determine the economic torque based on the acceleration.

[0170] The economic torque determination device 500 for the highway ramp scenario provided in the above embodiment can implement the technical solution described in the above embodiment of the economic torque determination method for the highway ramp scenario. The specific implementation principles of the above modules or units can refer to the corresponding contents in the embodiment of the economic torque determination method for the highway ramp scenario, which will not be repeated here.

[0171] like Figure 6 As shown, the present invention also provides an electronic device 600. The electronic device 600 includes a processor 601, a memory 602 and a display 603. Figure 6 Only some components of the electronic device 600 are shown, but it should be understood that it is not required to implement all of the components shown, and more or fewer components may be implemented instead.

[0172] In some embodiments, the processor 601 may be a central processing unit (CPU), a microprocessor or other data processing chip, used to run program codes or process data stored in the memory 602, such as the method for determining the economic torque in the highway ramp scenario of the present invention.

[0173] In some embodiments, the processor 601 may be a single server or a server group. The server group may be centralized or distributed. In some embodiments, the processor 601 may be local or remote. In some embodiments, the processor 601 may be implemented in a cloud platform. In some embodiments, the cloud platform may include a private cloud, a public cloud, a hybrid cloud, a community cloud, a distributed cloud, an internal cloud, a multi-cloud, etc., or any combination thereof.

[0174] In some embodiments, the memory 602 may be an internal storage unit of the electronic device 600, such as a hard disk or memory of the electronic device 600. In other embodiments, the memory 602 may also be an external storage device of the electronic device 600, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc., equipped on the electronic device 600.

[0175] Furthermore, the memory 602 may include both an internal storage unit of the electronic device 600 and an external storage device. The memory 602 is used to store application software installed in the electronic device 600 and various data.

[0176] In some embodiments, the display 603 may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, an organic light-emitting diode (OLED) touch device, etc. The display 603 is used to display information on the electronic device 600 and to display a visual user interface. The components 601-603 of the electronic device 600 communicate with each other via a system bus.

[0177] In one embodiment, when the processor 601 executes the economic torque determination program in the highway ramp scenario in the memory 602, the following steps may be implemented:

[0178] Merging the ramp slices based on the road types corresponding to the ramp slices to determine a merged fused ramp; the ramp slices are obtained by slicing the road in front of the vehicle;

[0179] Determining the acceleration of the vehicle based on the slope and the length of the blended ramp;

[0180] Based on the acceleration, an economic torque is determined.

[0181] It should be understood that: when the processor 601 executes the economic torque determination program in the highway ramp scenario in the memory 602, in addition to the above functions, other functions can also be implemented. For details, please refer to the description of the corresponding method embodiment above.

[0182] Furthermore, the embodiment of the present invention does not specifically limit the type of the electronic device 600 mentioned, and the electronic device 600 may be a portable electronic device such as a mobile phone, a tablet computer, a personal digital assistant (PDA), a wearable device, a laptop computer, etc. Exemplary embodiments of portable electronic devices include but are not limited to portable electronic devices equipped with IOS, Android, Microsoft or other operating systems. The above-mentioned portable electronic device may also be other portable electronic devices, such as a laptop computer with a touch-sensitive surface (e.g., a touch panel). It should also be understood that in some other embodiments of the present invention, the electronic device 600 may not be a portable electronic device, but a desktop computer with a touch-sensitive surface (e.g., a touch panel).

[0183] Accordingly, an embodiment of the present invention also provides a computer-readable storage medium, which is used to store computer-readable programs or instructions. When the program or instructions are executed by a processor, it can implement the steps or functions of the economic torque determination method in the highway ramp scenario provided by the above-mentioned method embodiments.

[0184] On the other hand, the present invention also provides a computer program product, which includes a computer program. The computer program can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the steps or functions of the method for determining the economic torque in the highway ramp scenario provided in the above-mentioned method embodiments.

[0185] Those skilled in the art will appreciate that all or part of the processes of the above-mentioned embodiments can be implemented by instructing related hardware (such as a processor, a controller, etc.) through a computer program, and the computer program can be stored in a computer-readable storage medium, wherein the computer-readable storage medium is a disk, an optical disk, a read-only storage memory, or a random access memory, etc.

[0186] The economic torque determination method, device and medium for the highway ramp scenario provided by the present invention are introduced in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A method for determining economic torque in a highway ramp scenario, characterized in that: include: Merging the ramp slices based on the road types corresponding to the ramp slices to determine a merged fusion ramp; The ramp slice is obtained by slicing the road in front of the vehicle; Determining the acceleration of the vehicle based on the slope and the length of the blended ramp; determining an economic torque based on the acceleration; The merging the ramp slices based on the road types corresponding to the ramp slices to determine the merged fused ramp includes: Traversing the ramp slices, when determining that the road type of the current ramp slice is an uphill type, determining the sequence number of the current ramp slice as the starting sequence number; Traversing the ramp slices based on the starting sequence number, and when determining that the road type of the next ramp slice is an uphill type, merging the next ramp slice with the current ramp slice, and determining the sequence number of the next ramp slice as the end sequence number; When the road type of the next ramp slice is a downhill type or a flat road type, the traversal is stopped and the merged fused ramp is obtained.

2. The method for determining the economic torque in a highway ramp scenario according to claim 1, characterized in that: Before determining the acceleration of the vehicle based on the slope and the slope length of the fused ramp, the method further includes: Based on the starting sequence number and the ending sequence number, the slope and the slope length of the fusion ramp are determined.

3. The method for determining the economic torque in a highway ramp scenario according to claim 2, characterized in that: The determining the acceleration of the vehicle based on the slope and the slope length of the fused ramp comprises: Divide the preset slope into sections to obtain multiple slope values; Divide the preset slope length into sections to obtain multiple slope length values; Each slope value is matched with a different slope length value, and the corresponding acceleration value is determined by a simulation model; the simulation model is a vehicle dynamics model built based on trucksim and matlab; Constructing an acceleration table based on the corresponding relationship between the slope value, the slope length value and the acceleration value; Based on the gradient and the length of the blended ramp, the acceleration of the vehicle is determined in the acceleration table.

4. The method for determining the economic torque in a highway ramp scenario according to claim 3, characterized in that: The determining of the economic torque based on the acceleration includes: determining an acceleration resistance based on the acceleration; determining a driving force based on the rolling resistance, air resistance, slope resistance and the acceleration resistance of the vehicle; Based on the driving force, the economic torque is determined.

5. The method for determining the economic torque in a highway ramp scenario according to claim 4, characterized in that: The expression of the economic torque is as follows: in, T represents economic torque, Indicates driving force, represents the wheel radius, Indicates the gear ratio. Indicates the transmission ratio of the final reducer. Indicates transmission efficiency.

6. A device for determining economic torque in a high-speed road ramp scenario, characterized in that: include: A merging module, configured to merge the ramp slices based on the road types corresponding to the ramp slices, and determine a merged fused ramp; The ramp slice is obtained by slicing the road in front of the vehicle; A first determination module, configured to determine the acceleration of the vehicle based on the slope and the slope length of the fused ramp; a second determination module, configured to determine an economic torque based on the acceleration; The merging the ramp slices based on the road types corresponding to the ramp slices to determine the merged fused ramp includes: Traversing the ramp slices, when determining that the road type of the current ramp slice is an uphill type, determining the sequence number of the current ramp slice as the starting sequence number; Traversing the ramp slices based on the starting sequence number, and when determining that the road type of the next ramp slice is an uphill type, merging the next ramp slice with the current ramp slice, and determining the sequence number of the next ramp slice as the end sequence number; When the road type of the next ramp slice is a downhill type or a flat road type, the traversal is stopped and the merged fused ramp is obtained.

7. An electronic device, characterized in that: comprising a memory and a processor, wherein: The memory is used to store programs; The processor is coupled to the memory and is used to execute the program stored in the memory to implement the method for determining the economic torque in a highway ramp scenario as described in any one of claims 1 to 5.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for determining the economic torque in a highway ramp scenario as described in any one of claims 1 to 5 is implemented.

9. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the method for determining the economic torque in a highway ramp scenario as described in any one of claims 1 to 5 is implemented.

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