CN116424338A - Wheel slip ratio calculation method, device, electronic equipment and storage medium - Google Patents
Wheel slip ratio calculation method, device, electronic equipment and storage medium Download PDFInfo
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W40/00—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models
- B60W40/10—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models related to vehicle motion
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W40/00—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models
- B60W40/10—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models related to vehicle motion
- B60W40/101—Side slip angle of tyre
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W2520/00—Input parameters relating to overall vehicle dynamics
- B60W2520/10—Longitudinal speed
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
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- B—PERFORMING OPERATIONS; TRANSPORTING
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- B60W2520/00—Input parameters relating to overall vehicle dynamics
- B60W2520/28—Wheel speed
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Abstract
The invention discloses a wheel slip rate calculation method, a device, electronic equipment and a storage medium, wherein the method comprises the following steps: calculating absolute speeds of the solid wheels relative to the reference wheels in the X direction and the Y direction of the vehicle body according to the sub-speeds of the center translation speed of the reference wheels in the X direction and the Y direction of the vehicle body and the sub-speeds of the relative linear speeds of the solid wheels relative to the reference wheels in the X direction and the Y direction of the vehicle body caused by the rotation movement of the rigid bodies; calculating the maximum value and the minimum value of the absolute speeds of the entity wheel relative to all the reference wheels in the rotating direction according to the absolute speeds of the entity wheel relative to the reference wheels in the X direction and the Y direction of the vehicle body; calculating real-time slip rate of the wheels according to the translation speed of the center of the entity wheel and the maximum value and the minimum value of the absolute speeds of the entity wheel relative to all reference wheels in the rotation direction; the algorithm has high universality, can ensure the normal realization of the anti-skid and anti-lock braking functions of the vehicle drive, and can further improve the running safety of the vehicle.
Description
Technical Field
The invention belongs to the technical field of vehicle braking, and particularly relates to a wheel slip rate calculation method, a device, electronic equipment and a storage medium.
Background
Whether a traditional fuel vehicle or a new energy electric vehicle, the driving anti-skid and braking anti-lock of a vehicle chassis are important and safe functional configurations. The accurate calculation of the slip rate of each wheel is a basis for driving anti-skid and anti-lock braking functions, if the slip rate calculation of each wheel is inaccurate, false triggering of driving anti-skid and anti-lock braking or incapability of normal triggering or abnormal torque control of each wheel after triggering can be caused, and the like, so that the safe running of the vehicle can be greatly influenced. The accurate calculation of the slip ratio is therefore the basis for safe running of the vehicle.
The existing slip ratio calculation method only adopts the method that the wheel speed of each wheel is divided by the vehicle speed at the center of the vehicle to obtain. The scheme is only suitable for the characteristic that the vehicle is in a straight running condition, if the vehicle is in a steering running state, the difference between the actual running wheel speed of each wheel and the vehicle speed at the center of the vehicle is large, especially when the vehicle is in a large steering small turning radius, the difference is large, so that inaccurate or erroneous calculation of the slip rate of each wheel can cause false triggering of driving anti-slip and braking anti-lock, abnormal torque control of each wheel after normal triggering or triggering, and the like, and the running safety of the vehicle can be seriously influenced.
Therefore, there is an urgent need for a method for calculating and determining a wheel slip rate, which is applicable to a vehicle with mechanical steering, a vehicle with steering structure but with differential speed, and a vehicle with any number of axles, and has no limitation or requirement on the chassis configuration of the vehicle, and has high algorithm universality.
Disclosure of Invention
Aiming at the defects or improvement demands of the prior art, the invention provides a wheel slip rate calculation method, a device, electronic equipment and a storage medium, wherein the theoretical speed of each wheel is calculated based on the yaw rate, and the slip rate of each wheel is calculated based on the theoretical speed; the method is applicable to not only mechanical ackerman steering automobiles, but also automobiles without steering structures and realizing vehicle steering through differential speed, and is also applicable to automobiles with any axle number, has no limit or requirement on the chassis configuration of the automobiles, the algorithm universality is high, the slip ratio of each wheel at the position can be accurately calculated, the normal realization of the anti-skid and anti-lock braking functions of the driving of the automobile can be ensured, and the running safety of the automobile can be further improved.
In order to achieve the above object, an aspect of the present invention provides a wheel slip ratio calculation method including the steps of:
Less than or equal to 1: calculating absolute speeds of the solid wheels relative to the reference wheels on the reference axles in the X direction and the Y direction of the vehicle body according to the sub-speeds of the translation speeds of the centers of the reference wheels on the reference axles in the X direction and the Y direction of the vehicle body and the sub-speeds of the relative linear speeds of the solid wheels relative to the reference wheels on the reference axles in the X direction and the Y direction of the vehicle body caused by the rotation motion of the rigid bodies;
and is less than or equal to 2: calculating the maximum value and the minimum value of the absolute speeds of the solid wheels relative to the reference wheels on the reference axles in the rotating direction and the absolute speeds of the solid wheels relative to the reference wheels on all the reference axles in the rotating direction according to the absolute speeds of the solid wheels relative to the reference wheels on the reference axles in the vehicle body X direction and the vehicle body Y direction;
s3: and calculating the real-time slip rate of the wheels according to the translation speed of the center of the entity wheel and the maximum value and the minimum value of the absolute speeds of the entity wheel relative to the reference wheels on all the reference axles in the rotating direction.
Further, the partial velocity of the translational velocity of the reference wheel center on the reference axle in the vehicle body X direction in step Σ.1 is represented by the formula (1):
VX kt ＝V kt *cosθ kt (1)
wherein f is the number of the left or right reference wheel, t e {1,2}, where t is 1 for the left reference wheel and t is 2 for the right reference wheel; k is the serial number of the reference axle numbered from the head in turn, k is [1, n ] ]H is the total number of reference axles; v (V) kt A translational speed that is the left or right reference wheel center of the kth reference axle; θ kt Is the included angle between the left or right reference wheel of the kth reference axle and the X direction of the vehicle body,
the wheels are positive towards the right side of the vehicle body and negative towards the left side of the vehicle body; VX (X) kt A partial speed of the translational speed of the center of the reference wheel on the left side or the right side of the kth reference axle in the X direction of the vehicle body;
the sub-speed of the translational speed of the reference wheel center on the reference axle in the vehicle body Y direction in step S1 is represented by (2):
VY kt ＝V kt *sinθ kt (2)
wherein VY kt The translational speed of the center of the wheel is referenced to the left or right of the kth reference axle in the sub-speed of the vehicle body Y direction.
Further, the relative linear velocity of the solid wheel relative to the reference wheel on the reference axle resulting from the rigid body rotational motion in step S1 is calculated by (5):
V ij(kt) ＝w*l ij(kt) (5)
wherein j is the number of the left or right physical wheel, wherein 1 represents the left wheel and 2 represents the right wheel; i is the serial number of the axle of the vehicle, which is numbered sequentially from the head of the vehicle; v (V) ij(kt) Causing a relative linear velocity of the left or right solid wheel of the ith axle relative to the left or right reference wheel of the kth reference axle for rigid body rotation; w is the yaw rate of the vehicle rotation, obtained by an angular velocity sensor mounted in the center of the vehicle, and the vehicle is positive in reverse time and negative in clockwise direction; l (L) ij(kt) Is the distance between the left or right solid wheel of the ith axle and the left or right reference wheel of the kth reference shaft;
in step S1, the relative linear velocity of the solid wheel relative to the reference wheel on the reference axle is calculated by the following method (8):
wherein: VX (X) ij(kt) Causing the right or left side of the ith axle to be solid for rigid body rotationA component of the relative linear velocity of the body wheel in the X-direction of the body relative to the left or right reference wheel on the kth reference axle; vY ij(kt) A component in the Y direction of the vehicle body of the relative linear velocity of the left or right solid wheel of the ith axle relative to the left or right reference wheel on the kth reference axle caused by the rotation of the rigid body; alpha ij(kt) Is the included angle between the line vector of the left or right solid wheel of the ith axle and the left or right reference wheel of the kth reference axle and the X direction of the car body, alpha ij(kt) ∈[-π，π]。
Further, the absolute speeds of the physical wheels in the vehicle body X direction and the vehicle body Y direction relative to the reference wheels on the reference axles in step S1 are calculated by (10):
wherein: VX1 ij(kt) The absolute resultant velocity of the left or right solid wheel of the ith axle relative to the left or right reference wheel on the kth reference axle in the direction of the vehicle body X; vY1 ij(kt) The absolute resultant velocity in the vehicle body Y of the left or right hand solid wheel of the ith axle relative to the left or right hand reference wheel on the kth reference axle.
Further, the absolute speed of the physical wheel in the rotational direction with respect to the reference wheel on the reference axle in step S2 is calculated by the formula (11):
V1 ij(kt) ＝|VX1 ij(kt) *cosθ ij +VY1 ij(kt) *sinθ ij | (11)
wherein: v1 ij(kt) Absolute speed in the rotational direction of the left or right solid wheel of the ith axle relative to the left or right reference wheel on the kth reference axle; θ ij The included angle between the solid wheel on the left side or the right side of the ith axle and the X direction of the vehicle body,
the wheels are positive towards the right side of the vehicle body and negative towards the left side of the vehicle body;
for a vehicle without a mechanical steering structure, θ kt =0 and θ ij ＝0。
Further, in step S2, the maximum and minimum values of the absolute speeds of the physical wheels in the rotational direction with respect to the reference wheels on all the reference axles are calculated by the formula (12):
wherein: vmin ij The minimum value of absolute speed when all wheels of the whole vehicle are used as reference wheels is adopted for the left or right entity wheel of the ith axle; vmax ij The maximum value of the absolute speed when all wheels of the whole vehicle are taken as reference wheels is adopted for the left or right entity wheels of the ith axle.
Further, the real-time slip ratio of the wheel in step S3 is calculated by the formula (13):
wherein: s is S ij Slip ratio of the solid wheel on the left side or the right side of the ith axle; beta is the state of braking or driving of the vehicle; v (V) ij The translation speed of the center of the wheel of the entity on the left or right side of the ith axle, calculated on the basis of the wheel speed, is equal to V kt Essentially a variable, numbered differently; v1 is a closing speed threshold value of dynamic calculation of the slip rate; v2 is a dynamically calculated opening speed threshold, and V2>V1; v2 and V1 are calibratable modification parameters;
if the vehicle is in a braking state and the wheel rotation speed in an unlocked state is maximum, vmax ij Effectively, the value of beta is 1;
if the vehicle is in a driving state and the wheel rotation speed is minimum in a non-slip state, vmin ij Effectively, the value of beta is-1.
A second aspect of the present invention provides a wheel slip ratio calculation apparatus including:
the first calculation module is used for calculating absolute speeds of the solid wheels relative to the reference wheels on the reference axle in the directions of the vehicle body X and the vehicle body Y according to the partial speeds of the translation speed of the center of the reference wheels on the reference axle in the directions of the vehicle body X and the vehicle body Y and the partial speeds of the relative linear speeds of the solid wheels relative to the reference wheels on the reference axle in the directions of the vehicle body X and the vehicle body Y caused by the rotation motion of the rigid bodies;
the second calculation module calculates the maximum value and the minimum value of the absolute speed of the solid wheel relative to the reference wheel on the reference axle in the rotating direction and the absolute speed of the solid wheel relative to the reference wheels on all the reference axles in the rotating direction according to the absolute speeds of the solid wheel relative to the reference wheels on the reference axle in the vehicle body X direction and the vehicle body Y direction;
And the third calculation module is used for calculating the real-time slip rate of the wheels according to the translation speed of the center of the entity wheel and the maximum value and the minimum value of the absolute speeds of the entity wheel relative to the reference wheels on all the reference axles in the rotating direction.
A third aspect of the invention provides an electronic device comprising a processor and a memory, the processor and the memory being interconnected;
the memory is used for storing a computer program;
the processor is configured to execute the above-described wheel slip rate calculation method when the computer program is invoked.
A fourth aspect of the present invention provides a computer-readable storage medium storing a computer program that is executed by a processor to implement the above-described wheel slip ratio calculation method.
In general, the above technical solutions conceived by the present invention, compared with the prior art, enable the following beneficial effects to be obtained:
according to the wheel slip rate calculation method, the theoretical speed of each wheel is calculated based on the yaw rate, and the slip rate of each wheel is calculated based on the theoretical speed; specifically, calculating absolute speeds of the solid wheels relative to the reference wheels on the reference axles in the directions of the vehicle body X and the vehicle body Y according to the sub-speeds of the translation speeds of the centers of the reference wheels on the reference axles in the directions of the vehicle body X and the vehicle body Y and the sub-speeds of the relative linear speeds of the solid wheels relative to the reference wheels on the reference axles in the directions of the vehicle body X and the vehicle body Y caused by the rotation motion of the rigid bodies; calculating the maximum value and the minimum value of the absolute speeds of the solid wheels relative to the reference wheels on the reference axles in the rotating direction and the absolute speeds of the solid wheels relative to the reference wheels on all the reference axles in the rotating direction according to the absolute speeds of the solid wheels relative to the reference wheels on the reference axles in the vehicle body X direction and the vehicle body Y direction; calculating real-time slip rate of the wheels according to the translation speed of the center of the entity wheel and the maximum value and the minimum value of the absolute speeds of the entity wheel relative to the reference wheels on all the reference axles in the rotating direction; the invention calculates the theoretical speed of each wheel based on the yaw rate, and calculates the slip rate of each wheel based on the theoretical speed; the slip ratio of each wheel can still be accurately calculated as long as the yaw rate of the vehicle is obtained in real time and the size of the vehicle is combined under extreme working conditions such as straight running or steering running state, understeer state or oversteer state and the like of the vehicle. The invention has wide applicability and can be suitable for automobiles with chassis of any configuration. The slip rate obtained through kinematic calculation can be suitable for vehicles which do not have mechanical steering structures and steer through differential speed, can also be suitable for automobiles with mechanical steering structures, and can also be suitable for automobiles with multiple axles or different wheel tracks; the method can solve the problems that the existing slip rate calculation method only adopts the wheel speed of each wheel divided by the vehicle speed at the center of the vehicle to obtain the slip rate, the method can only be suitable for the vehicle in a straight running working condition, if the vehicle is in a steering running state, the actual running wheel speed of each wheel is greatly different from the vehicle speed at the center of the vehicle, and the slip rate calculation of each wheel is inaccurate or wrong, so that the driving anti-slip and anti-lock braking are triggered mistakenly or the torque control of each wheel after being triggered can not be triggered normally or triggered is abnormal, and the running safety of the vehicle is seriously affected.
Drawings
FIG. 1 is a flow chart of a method for calculating a wheel slip ratio according to an embodiment of the present invention;
FIG. 2 is a schematic diagram showing a speed geometry of an automobile without steering structure using differential steering according to an embodiment of the present invention;
FIG. 3 is a schematic diagram of a wheel slip ratio calculating apparatus according to an embodiment of the present invention;
fig. 4 is a schematic physical structure of an electronic device according to an embodiment of the invention.
Detailed Description
The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention. In addition, the technical features of the embodiments of the present invention described below may be combined with each other as long as they do not collide with each other.
It should be understood that, although the steps in the flowcharts of the figures are shown in order as indicated by the arrows, these steps are not necessarily performed in order as indicated by the arrows. The steps are not strictly limited in order and may be performed in other orders, unless explicitly stated herein. Moreover, at least some of the steps in the flowcharts of the figures may include a plurality of sub-steps or stages that are not necessarily performed at the same time, but may be performed at different times, the order of their execution not necessarily being sequential, but may be performed in turn or alternately with other steps or at least a portion of the other steps or stages.
The accurate calculation of the slip rate is the basis for safe running of the vehicle. The existing slip ratio calculation method only adopts the method that the wheel speed of each wheel is divided by the vehicle speed at the center of the vehicle to obtain. The scheme is only suitable for the characteristic that the vehicle is in a straight running condition, if the vehicle is in a steering running state, the difference between the actual running wheel speed of each wheel and the vehicle speed at the center of the vehicle is large, especially when the vehicle is in a large steering small turning radius, the difference is large, so that inaccurate or erroneous calculation of the slip rate of each wheel can cause false triggering of driving anti-slip and braking anti-lock, abnormal torque control of each wheel after normal triggering or triggering, and the like, and the running safety of the vehicle can be seriously influenced.
In view of the above problems in the related art, an embodiment of the present invention provides a wheel slip rate calculation method, which may be applied to a server, a terminal, a system including a terminal and a server, and implemented through interaction between the terminal and the server. The server may be implemented as a stand-alone server or as a server cluster formed by a plurality of servers. The terminal can be, but not limited to, various personal computers, notebook computers, smart phones, tablet computers, internet of things equipment and portable wearable equipment, and the internet of things equipment can be smart speakers, smart televisions, smart air conditioners, smart vehicle-mounted equipment and the like. The portable wearable device may be a smart watch, smart bracelet, headset, or the like. It should be noted that, the number of "plural" and the like mentioned in each embodiment of the present application refers to the number of "at least two", for example, "plural" refers to "at least two".
Before explaining the specific implementation of the embodiment of the present invention, a main application scenario of the embodiment of the present invention is explained. The embodiment of the invention provides a wheel slip rate calculation method, which is not only applicable to mechanical ackerman steering automobiles, but also applicable to automobiles which do not have steering structures and realize vehicle steering through differential speed, and is also applicable to automobiles with any axle number, has no limit and requirement on the chassis configuration of the automobiles, has high algorithm universality, can ensure the normal realization of driving anti-skid and braking anti-lock functions, and improves the running safety of the vehicles.
Note that, the vehicle body X direction referred to herein refers to a direction along the longitudinal center axis of the vehicle; the vehicle body Y direction refers to a direction along the vehicle transverse direction toward the center axis.
As shown in fig. 1, an aspect of the present invention provides a method for calculating a wheel slip ratio, which is applied to a server for illustration, and includes the steps of:
s1, calculating absolute speeds of the solid wheels relative to the reference wheels on the reference axles in the X direction and the Y direction of the vehicle body according to the speeds of the translation speeds of the centers of the reference wheels on the reference axles in the X direction and the Y direction of the vehicle body and the speeds of the relative linear speeds of the solid wheels relative to the reference wheels on the reference axles in the X direction and the Y direction of the vehicle body caused by the rotation movement of the rigid body;
S2, calculating the maximum value and the minimum value of the absolute speed of the solid wheel relative to the reference wheel on the reference axle in the rotating direction and the absolute speed of the solid wheel relative to the reference wheels on all the reference axles in the rotating direction according to the absolute speeds of the solid wheel relative to the reference wheels on the reference axle in the X direction and the Y direction of the vehicle body;
and S3, calculating the real-time slip rate of the wheels according to the translation speed of the center of the entity wheel and the maximum value and the minimum value of the absolute speeds of the entity wheel relative to the reference wheels on all the reference axles in the rotating direction.
Further, in the embodiment of the present invention, the translational speed of the center of the reference wheel on the reference axle in step S1 is calculated based on the actual rotational speeds of the respective reference wheels; the sub-speed of the translational speed of the reference wheel center on the reference axle in the vehicle body X direction in step S1 is represented by (1):
VX kt ＝V kt *cosθ kt (1)
wherein t is the number of the left or right reference wheel on the reference axle, t is {1,2}, where t is 1 for the left reference wheel and t is 2 for the right reference wheel; k is the serial number of the reference axle numbered from the head in turn, k is [1, n ]]N is the total number of reference axles; v (V) kt A translational speed that is the left or right reference wheel center of the kth reference axle; θ kt Is the included angle between the left or right reference wheel of the kth reference axle and the X direction of the vehicle body,
the wheels are positive towards the right side of the vehicle body and negative towards the left side of the vehicle body; VX (X) kt A partial speed of the translational speed of the center of the reference wheel on the left side or the right side of the kth reference axle in the X direction of the vehicle body;
the sub-speed of the translational speed of the reference wheel center on the reference axle in the vehicle body Y direction in step S1 is represented by (2):
VY kt ＝V kt *sinθ kt (2)
wherein VY kt The translational speed of the center of the wheel is referenced to the left or right of the kth reference axle in the sub-speed of the vehicle body Y direction.
Further, because the tire pressures of the reference wheels are inconsistent, the radii of the reference wheels are different, and the radii of the reference wheels need to be corrected according to the tire pressures of the reference wheels; thus, the translational speed of the reference wheel center is equal to the reference wheel rotational speed multiplied by the reference wheel correction radius; the translational velocity of the reference wheel center on the reference axle in step S1 is represented by formula (3):
V kt ＝w kt *τ kt (3)
wherein: w (w) kt The rotation speed of the left or right reference wheel of the kth reference axle is acquired through a sensor; τ kt A corrected radius for the left or right reference wheel of the kth reference axle;
wherein the corrected radius of the reference wheel on the reference axle is calculated by the following formula (4):
Wherein: τ kt A corrected radius for the left or right reference wheel of the kth reference axle; rmax kt Maximum tire radius for the left or right reference wheel of the kth reference axle; p is p kt The actual tire pressure of the reference wheel on the left side or the right side of the kth reference axle is obtained through a tire pressure sensor; pmin kt Minimum allowable tire pressure for the left or right reference wheel of the kth reference axle; pmax (pmax) kt Maximum allowable tire pressure for the left or right reference wheel of the kth reference axle; rmin kt The minimum tire radius of the reference wheel to the left or right of the kth reference axle;
if the actual tire pressure of the reference wheel on the left side or the right side of the kth reference axle is equal to the maximum allowable tire pressure, the correction radius of the reference wheel is equal to the maximum tire radius of the wheel; namely: if p kt ＝pmax kt T is then kt ＝rmax kt ；
If the actual tire pressure of the reference wheel on the left side or the right side of the kth reference axle is equal to the minimum allowable tire pressure, the corrected radius of the reference wheel is equal to the minimum tire radius of the wheel; namely: if p kt ＝pmin kt τ is then kt ＝rmin kt ；
If the actual tire pressure of the left or right reference wheel of the kth reference axle is greater than or equal to the minimum allowable tire pressure and less than or equal to the maximum allowable tire pressure, the corrected radius of the reference wheel is greater than or equal to the minimum tire radius of the wheel and less than or equal to the maximum tire radius of the wheel;
Namely: if pmin kt ≤p kt ≤pmax kt Then rmin kt ≤τ kt ≤rmax kt 。
Further, in the embodiment of the present invention, the relative linear velocity of the solid wheel with respect to the reference wheel on the reference axle is calculated by the formula (5) in the rigid body rotational motion in the step +.1:
V ij(kt) ＝＝w*l ij(kt) (5)
wherein j is the number of the left or right physical wheel, wherein 1 represents the left wheel and 2 represents the right wheel; i is the serial number of the axle sequentially numbered from the head; v (V) ij(kt) Causing a relative linear velocity of the left or right solid wheel of the ith axle relative to the left or right reference wheel of the kth reference axle for rigid body rotation; w is the yaw rate of the vehicle rotation, obtained by an angular velocity sensor mounted in the center of the vehicle, and the vehicle is positive in reverse time and negative in clockwise direction; l (L) ij (kt) is the distance between the left or right solid wheel of the ith axle and the left or right reference wheel of the kth reference axle;
further, when the vehicle is traveling straight, if there is no rotational movement, the yaw rate w of the vehicle rotation is equal to 0; when the vehicle runs left-hand, the vehicle does anticlockwise rotation, and the yaw rate w of the rotation of the vehicle is smaller than 0; the vehicle rotates right to run and does clockwise rotation, and the yaw rate w of the rotation of the vehicle is greater than 0;
Further, since the yaw rate of the vehicle rotation is very important, it is acquired by an angular velocity sensor; due to vibration in the vehicle movement process and the problem of sensor precision, in order to ensure the smoothness of the yaw rate of the vehicle rotation, sliding average filtering processing is required;
the sliding average filtering process of the yaw rate of the vehicle rotation is represented by formula (6):
wherein: w (a) is an a-th value of yaw rate of m vehicle rotations continuously acquired by the angular velocity sensor;
continuously acquiring a minimum value of yaw rate of rotation of each vehicle for the angle sensor; />
Continuously acquiring a maximum value of yaw rate of rotation of each vehicle for the angle sensor;
further, the distance l between the left or right solid wheel of the ith axle and the left or right reference wheel on the kth reference axle ij(kt) Calculated by formula (7):
wherein: d, d i Is the tread on the ith axle; d, d k Is the tread on the kth reference axle; d, d ik The wheelbase of the ith axle and the kth reference axle;
further, if the solid wheel on the i-th axle and the reference wheel on the k-th reference axle are on the same side, then |j-t|=0 or ||j-t| -1|=1, and if the solid wheel on the i-th axle and the reference wheel on the k-th reference axle are on different sides, then |j-t|=1 or ||j-t| -1|=0.
Further, as shown in fig. 2, in the embodiment of the present invention, the relative linear velocity of the solid wheel with respect to the reference wheel on the reference axle is calculated by the following equation (8) in the sub-velocity of the vehicle body X direction and the vehicle body Y direction due to the rigid body rotational motion in step S1:
wherein: VX (X) ij(kt) A component in the X direction of the vehicle body of a relative linear velocity of a left or right solid wheel of the ith axle relative to a left or right reference wheel on the kth reference axle caused by rotation of the rigid body; vY ij(kt) A component in the Y direction of the vehicle body of the relative linear velocity of the left or right solid wheel of the ith axle relative to the left or right reference wheel on the kth reference axle caused by the rotation of the rigid body; alpha ij(kt) Is the included angle between the line vector of the left or right solid wheel of the ith axle and the left or right reference wheel of the kth reference axle and the X direction of the car body, alpha ij(kt) ∈[-π，π]。
Further, according to the geometric positional relationship of the wheel mounting, it is known that: the included angle alpha between the line vector of the left or right solid wheel of the ith axle and the left or right reference wheel of the kth reference axle and the X direction of the vehicle body ij(kt) Represented by formula (9):
α ij(kt) ＝π-α kt(ij) (9)。
further, in the embodiment of the present invention, the absolute speeds of the physical wheels in the vehicle body X direction and the vehicle body Y direction with respect to the reference wheels on the reference axle in step S1 are calculated by the formula (10):
Wherein: VX1 ij(kt) The absolute resultant velocity of the left or right solid wheel of the ith axle relative to the left or right reference wheel on the kth reference axle in the direction of the vehicle body X; vY1 ij(kt) The absolute resultant velocity of the left or right solid wheel of the ith axle relative to the left or right reference wheel on the kth reference axle in the Y direction of the vehicle body; VX (X) ij(kt) Is justThe body rotation causes a component of the relative linear velocity of the left or right solid wheel of the ith axle relative to the left or right reference wheel on the kth reference axle in the X-direction of the vehicle body; VX (X) kt A partial speed of the translational speed of the center of the left or right reference wheel on the kth reference axle in the X direction of the vehicle body; vY ij(kt) A component in the Y direction of the vehicle body of the relative linear velocity of the left or right solid wheel of the ith axle relative to the left or right reference wheel on the kth reference axle caused by the rotation of the rigid body; vY kt Is the sub-speed of the translational speed of the center of the reference wheel on the kth reference axle in the Y direction of the vehicle body.
Further, in the embodiment of the present invention, the absolute speed of the solid wheel in the rotational direction with respect to the reference wheel on the reference axle in step S2 is calculated by the formula (11):
V1 ij(kt) ＝|VX1 ij(kt) *cosθ ij +VY1 ij(kt) *sinθ ij | (11)
wherein: v1 ij(kt) Absolute speed in the rotational direction of the left or right solid wheel of the ith axle relative to the left or right reference wheel on the kth reference axle; θ ij The included angle between the solid wheel on the left side or the right side of the ith axle and the X direction of the vehicle body,
the wheels are positive towards the right side of the vehicle body and negative towards the left side of the vehicle body; θ ij And theta kt For the same angle, the numbers are different.
Further, in the embodiment of the present invention, the maximum and minimum values in the absolute speeds of the solid wheels in the rotational direction with respect to the reference wheels on all the reference axles in step S2 are calculated by the formula (12):
wherein: vmin ij The minimum value of absolute speed when all wheels of the whole vehicle are used as reference wheels is adopted for the left or right entity wheel of the ith axle; vmax ij Left or right of the ith axleThe solid wheels adopt the maximum value of absolute speed when all wheels of the whole vehicle are reference wheels.
Further, in the embodiment of the present invention, the real-time slip rate of the wheel in step S3 is calculated by the formula (13):
wherein: s is S ij Slip ratio of the solid wheel on the left side or the right side of the ith axle; beta is the state of braking or driving of the vehicle; v (V) ij The translation speed of the center of the wheel of the entity on the left or right side of the ith axle, calculated on the basis of the wheel speed, is equal to V kt Essentially a variable, numbered differently; v1 is a closing speed threshold value of dynamic calculation of the slip rate; v2 is a dynamically calculated opening speed threshold, and V2 is greater than V1; v2 and V1 are calibratable modification parameters.
Namely, when the translational speed of the center of the solid wheel is smaller than or equal to the closing speed threshold value dynamically calculated by the slip rate, the real-time slip rate of the wheel is zero;
when the translational speed of the center of the solid wheel is greater than or equal to the opening speed threshold value dynamically calculated by the slip rate, the real-time slip rate of the wheel is as follows:
further, because the tire pressures of the wheels are inconsistent, the radius of each wheel is different, and the radius of each wheel needs to be corrected according to the tire pressure of each wheel; thus, the translational velocity of the center of the left or right solid wheel of the i-th axle is equal to the left or right solid wheel rotational speed of the i-th axle multiplied by the corrected radius of the left or right solid wheel of the i-th axle; that is, the translational velocity of the solid wheel center is represented by formula (14):
V ij ＝w ij *τ ij (14)
wherein: vx (Vx) j Translation of the centre of the wheel of the entity to the left or right of the ith axleA speed; w (w) ij The rotation speed of the solid wheel at the left side or the right side of the ith axle is acquired by a sensor; τ ij Is the corrected radius of the right or left solid wheel of the ith axle.
Further, if the vehicle is in a braking state and the wheel rotation speed in an unlocked state is maximum, vmax il Effectively, the value of beta is 1; if the vehicle is in a driving state and the wheel rotation speed is minimum in a non-slip state, vmin ij Effectively, the value of beta is-1.
Further, the minimum value of the absolute speed ymin when the vehicle speed is the smallest value of the absolute speed ymin when the solid wheels on the left or right side of the ith axle use all wheels of the whole vehicle as reference wheels ij And a maximum value ymax ij During the switching, the abrupt change of the slip rate caused by the switching between the abrupt acceleration and the abrupt deceleration is avoided through the slope process control.
Further, for an automobile without a steering structure vehicle, let θ kt =0 and θ ij =0, and the slip ratio can be accurately calculated in the steering or straight running process by carrying out calculation in formulas (12) - (13).
The wheel slip rate calculation method provided by the invention is used for calculating the theoretical speed of each wheel based on the yaw rate, calculating the slip rate of each wheel based on the theoretical speed, and is not only applicable to mechanical ackerman steering automobiles, but also applicable to automobiles which do not have steering structures and realize vehicle steering through differential speed, and simultaneously applicable to automobiles with any axle number, and has no limitation and requirement on the chassis configuration of the automobiles, and the algorithm universality is high; the invention can ensure that the anti-skid and anti-lock braking functions of the vehicle are normally realized, thereby improving the running safety of the vehicle; the method can solve the problems that the existing slip rate calculation method only adopts the wheel speed of each wheel divided by the vehicle speed at the center of the vehicle to obtain the slip rate, the method can only be suitable for the vehicle in a straight running working condition, if the vehicle is in a steering running state, the actual running wheel speed of each wheel is greatly different from the vehicle speed at the center of the vehicle, and the slip rate calculation of each wheel is inaccurate or wrong, so that the driving anti-slip and anti-lock braking are triggered mistakenly or the torque control of each wheel after being triggered can not be triggered normally or triggered is abnormal, and the running safety of the vehicle is seriously affected.
As shown in fig. 3, a second aspect of the present invention provides a device for calculating a wheel slip ratio, including a first calculation module, a second calculation module, and a third calculation module.
The first calculation module is used for calculating absolute speeds of the solid wheels relative to the reference wheels on the reference axle in the directions of the vehicle body X and the vehicle body Y according to the partial speeds of the translation speed of the center of the reference wheels on the reference axle in the directions of the vehicle body X and the vehicle body Y and the partial speeds of the relative linear speeds of the solid wheels relative to the reference wheels on the reference axle in the directions of the vehicle body X and the vehicle body Y caused by the rotation motion of the rigid bodies;
the second calculation module calculates the maximum value and the minimum value of the absolute speed of the solid wheel relative to the reference wheel on the reference axle in the rotating direction and the absolute speed of the solid wheel relative to the reference wheels on all the reference axles in the rotating direction according to the absolute speeds of the solid wheel relative to the reference wheels on the reference axle in the vehicle body X direction and the vehicle body Y direction;
and the third calculation module is used for calculating the real-time slip rate of the wheels according to the translation speed of the center of the entity wheel and the maximum value and the minimum value of the absolute speeds of the entity wheel relative to the reference wheels on all the reference axles in the rotating direction.
It should be noted that, the calculating device of the wheel slip ratio provided by the embodiment of the present invention may be a computer program running in a computer device, including program code, for example, the calculating device of the wheel slip ratio is an application software; the calculation device of the wheel slip ratio can be used for executing the corresponding steps in the method provided by the embodiment of the invention.
In some possible implementations, the apparatus for calculating a wheel slip ratio provided in this embodiment may be implemented by combining software and hardware, and by way of example, the apparatus for calculating a wheel slip ratio in this embodiment may be a processor in the form of a hardware decoding processor that is programmed to perform the method for calculating a wheel slip ratio provided in this embodiment, for example, the processor in the form of a hardware decoding processor may employ one or more application specific integrated circuits (ASIC, application Specific Integrated Circuit), digital signal processor (digital signal processor, DSP), programmable logic device (PLD, programmable Logic Device), complex programmable logic device (CPLD, complex Programmable Logic Device), field programmable gate array (FPGA, field-Programmable Gate Array), or other electronic component.
In some possible implementations, the device for calculating the wheel slip ratio provided in this embodiment may be implemented in software, which may be software in the form of a program or a plug-in unit, and includes a series of modules to implement the control method provided in the embodiment of the present invention.
The calculation device for the wheel slip rate provided by the embodiment calculates the theoretical speed of each wheel based on the yaw rate, and calculates the slip rate of each wheel based on the theoretical speed; specifically, calculating absolute speeds of the solid wheels relative to the reference wheels on the reference axles in the directions of the vehicle body X and the vehicle body Y according to the sub-speeds of the translation speeds of the centers of the reference wheels on the reference axles in the directions of the vehicle body X and the vehicle body Y and the sub-speeds of the relative linear speeds of the solid wheels relative to the reference wheels on the reference axles in the directions of the vehicle body X and the vehicle body Y caused by the rotation motion of the rigid bodies; calculating the maximum value and the minimum value of the absolute speeds of the solid wheels relative to the reference wheels on the reference axles in the rotating direction and the absolute speeds of the solid wheels relative to the reference wheels on all the reference axles in the rotating direction according to the absolute speeds of the solid wheels relative to the reference wheels on the reference axles in the vehicle body X direction and the vehicle body Y direction; calculating real-time slip rate of the wheels according to the translation speed of the center of the entity wheel and the maximum value and the minimum value of the absolute speeds of the entity wheel relative to the reference wheels on all the reference axles in the rotating direction; the method is applicable to not only mechanical Ackerman steering automobiles, but also automobiles without steering structures for realizing vehicle steering through differential speed, and also automobiles with any axle number, has no limit and requirement on the chassis configuration of the automobiles, has high algorithm universality, can ensure the normal realization of the anti-skid and anti-lock braking functions of the driving of the vehicles, and further can improve the running safety of the vehicles; the method can solve the problems that the existing slip rate calculation method only adopts the wheel speed of each wheel divided by the vehicle speed at the center of the vehicle to obtain the slip rate, the method can only be suitable for the vehicle in a straight running working condition, if the vehicle is in a steering running state, the actual running wheel speed of each wheel is greatly different from the vehicle speed at the center of the vehicle, and the slip rate calculation of each wheel is inaccurate or wrong, so that the driving anti-slip and anti-lock braking are triggered mistakenly or the torque control of each wheel after being triggered can not be triggered normally or triggered is abnormal, and the running safety of the vehicle is seriously affected.
The method for calculating the wheel slip ratio according to the first aspect of the present invention is implemented by an electronic device, as shown in fig. 4, and a third aspect of the present invention provides an electronic device, which includes: at least one processor (processor), a communication interface (Communications Interface), at least one memory (memory) and a communication bus, wherein the at least one processor, the communication interface, the at least one memory, and the communication bus complete communication with each other; the at least one processor may invoke logic instructions in the at least one memory to perform all or part of the steps of the methods provided by the various method embodiments described above; that is, the memory stores program instructions executable by the processor, the processor invoking the program instructions to be able to perform the method of calculating wheel slip ratio provided by any of the various implementations of the first aspect.
The logic instructions in at least one of the memories described above may be implemented in the form of a software functional unit and may be stored in a computer-readable storage medium when sold or used as a stand-alone product. Based on such understanding, a fourth aspect of the present invention provides a non-transitory computer readable storage medium for storing computer instructions by which a computer is caused to perform a method of calculating a wheel slip ratio provided by any of the various implementations of the first aspect of the present invention; the aspects of the present invention, or portions thereof, may be embodied in the form of a software product stored on a storage medium, including instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of a method according to various method embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a random access Memory (RAM, random Access Memory), a magnetic disk, or an optical disk, or other various media capable of storing program codes.
The embodiment of the invention provides a computer readable storage medium, which calculates the theoretical speed of each wheel based on the yaw rate and calculates the slip rate of each wheel based on the theoretical speed; specifically, calculating absolute speeds of the solid wheels relative to the reference wheels on the reference axles in the directions of the vehicle body X and the vehicle body Y according to the sub-speeds of the translation speeds of the centers of the reference wheels on the reference axles in the directions of the vehicle body X and the vehicle body Y and the sub-speeds of the relative linear speeds of the solid wheels relative to the reference wheels on the reference axles in the directions of the vehicle body X and the vehicle body Y caused by the rotation motion of the rigid bodies; calculating the maximum value and the minimum value of the absolute speeds of the solid wheels relative to the reference wheels on the reference axles in the rotating direction and the absolute speeds of the solid wheels relative to the reference wheels on all the reference axles in the rotating direction according to the absolute speeds of the solid wheels relative to the reference wheels on the reference axles in the vehicle body X direction and the vehicle body Y direction; calculating real-time slip rate of the wheels according to the translation speed of the center of the entity wheel and the maximum value and the minimum value of the absolute speeds of the entity wheel relative to the reference wheels on all the reference axles in the rotating direction; the method is applicable to not only mechanical Ackerman steering automobiles, but also automobiles without steering structures for realizing vehicle steering through differential speed, and also automobiles with any axle number, has no limit and requirement on the chassis configuration of the automobiles, has high algorithm universality, can ensure the normal realization of the anti-skid and anti-lock braking functions of the driving of the vehicles, and further can improve the running safety of the vehicles; the method can solve the problems that the existing slip rate calculation method only adopts the wheel speed of each wheel divided by the vehicle speed at the center of the vehicle to obtain the slip rate, the method can only be suitable for the vehicle in a straight running working condition, if the vehicle is in a steering running state, the actual running wheel speed of each wheel is greatly different from the vehicle speed at the center of the vehicle, and the slip rate calculation of each wheel is inaccurate or wrong, so that the driving anti-slip and anti-lock braking are triggered mistakenly or the torque control of each wheel after being triggered can not be triggered normally or triggered is abnormal, and the running safety of the vehicle is seriously affected.
It will be readily appreciated by those skilled in the art that the foregoing description is merely a preferred embodiment of the invention and is not intended to limit the invention, but any modifications, equivalents, improvements or alternatives falling within the spirit and principles of the invention are intended to be included within the scope of the invention.
Claims (10)
1. The wheel slip rate calculating method is characterized by comprising the following steps of:
s1: calculating absolute speeds of the solid wheels relative to the reference wheels on the reference axles in the X direction and the Y direction of the vehicle body according to the sub-speeds of the translation speeds of the centers of the reference wheels on the reference axles in the X direction and the Y direction of the vehicle body and the sub-speeds of the relative linear speeds of the solid wheels relative to the reference wheels on the reference axles in the X direction and the Y direction of the vehicle body caused by the rotation motion of the rigid bodies;
s2: calculating the maximum value and the minimum value of the absolute speeds of the solid wheels relative to the reference wheels on the reference axles in the rotating direction and the absolute speeds of the solid wheels relative to the reference wheels on all the reference axles in the rotating direction according to the absolute speeds of the solid wheels relative to the reference wheels on the reference axles in the vehicle body X direction and the vehicle body Y direction;
s3: and calculating the real-time slip rate of the wheels according to the translation speed of the center of the entity wheel and the maximum value and the minimum value of the absolute speeds of the entity wheel relative to the reference wheels on all the reference axles in the rotating direction.
2. The wheel slip ratio calculation method according to claim 1, characterized in that the sub-speed of the translational speed of the reference wheel center on the reference axle in the vehicle body X direction in step S1 is represented by formula (1):
VX kt ＝V kt *cosθ kt (1)
wherein t is the number of the left or right reference wheel, t e {1,2}, where t is 1 for the left reference wheel and t is 2 for the right reference wheel; k is the serial number of the reference axle numbered from the head in turn, k E [ [1，n]N is the total number of reference axles; v (V) kt A translational speed that is the left or right reference wheel center of the kth reference axle; θ kt Is the included angle between the left or right reference wheel of the kth reference axle and the X direction of the vehicle body,
the wheels are positive towards the right side of the vehicle body and negative towards the left side of the vehicle body; VX (X) kt A partial speed of the translational speed of the center of the reference wheel on the left side or the right side of the kth reference axle in the X direction of the vehicle body;
the sub-speed of the translational speed of the reference wheel center on the reference axle in the vehicle body Y direction in step S1 is represented by (2):
VY kt ＝V kt *sinθ kt (2)
wherein VY kt The translational speed of the center of the wheel is referenced to the left or right of the kth reference axle in the sub-speed of the vehicle body Y direction.
3. The wheel slip ratio calculation method according to claim 2, wherein the relative linear velocity of the solid wheel with respect to the reference wheel on the reference axle is calculated by the formula (5) by the rigid body rotational motion in step S1:
V ij(kt) ＝w*l ij(kt) (5)
Wherein j is the number of the left or right wheel on the same axle, wherein 1 represents the left wheel and 2 represents the right wheel; i is the serial number of the axle of the vehicle, which is numbered sequentially from the head of the vehicle; v (V) ij(kt) Causing a relative linear velocity of the left or right solid wheel of the ith axle relative to the left or right reference wheel of the kth reference axle for rigid body rotation; w is the yaw rate of the vehicle rotation, obtained by an angular velocity sensor mounted in the center of the vehicle, and the vehicle is positive in reverse time and negative in clockwise direction; l (L) ij(kt) Is the distance between the left or right solid wheel of the ith axle and the left or right reference wheel of the kth reference shaft;
in step S1, the relative linear velocity of the solid wheel relative to the reference wheel on the reference axle is calculated by the following method (8):
wherein: VX (X) ij(kt) A component of the relative linear velocity of the left or right solid wheel of the ith axle relative to the left or right solid wheel of the kth reference axle in the X-direction of the vehicle body resulting from rotation of the rigid body; vY ij(kt) A component in the Y direction of the vehicle body of the relative linear velocity of the left or right solid wheel of the ith axle relative to the left or right reference wheel on the kth reference axle caused by the rotation of the rigid body; alpha ij(kt) Is the included angle between the line vector of the left or right solid wheel of the ith axle and the left or right reference wheel of the kth reference axle and the X direction of the car body, alpha ij(kt) ∈[-π，π]。
4. A wheel slip ratio calculation method according to claim 3, wherein the absolute speeds of the physical wheels with respect to the reference wheels on the reference axle in the vehicle body X direction and the vehicle body Y direction in step S1 are calculated by the formula (10):
wherein: VX1 ij(kt) The absolute resultant velocity of the left or right solid wheel of the ith axle relative to the left or right reference wheel on the kth reference axle in the direction of the vehicle body X; vY1 ij(kt) The absolute resultant velocity in the vehicle body Y of the left or right hand solid wheel of the ith axle relative to the left or right hand reference wheel on the kth reference axle.
5. The wheel slip ratio calculation method according to claim 4, wherein the absolute speed of the solid wheel in the rotational direction with respect to the reference wheel on the reference axle in step S2 is calculated by the formula (11):
V1 ij(kt) ＝|VX1 ij(kt) *cosθ ij +VY1 ij(kt) *sinθ ij | (11)
wherein: v1 ij(kt) Absolute speed in the rotational direction of the left or right solid wheel of the ith axle relative to the left or right reference wheel on the kth reference axle; θ ij The included angle between the solid wheel on the left side or the right side of the ith axle and the X direction of the vehicle body,
the wheels are positive towards the right side of the vehicle body and negative towards the left side of the vehicle body;
For a vehicle without a mechanical steering structure, θ kt =0 and θ ij ＝0。
6. The wheel slip ratio calculation method according to claim 5, wherein the maximum and minimum values of the absolute speeds of the solid wheels with respect to the reference wheels on all the reference axles in the rotation direction in step S2 are calculated by the formula (12):
wherein: vmin ij The minimum value of absolute speed when all wheels of the whole vehicle are used as reference wheels is adopted for the left or right entity wheel of the ith axle; vmax ij The maximum value of the absolute speed when all wheels of the whole vehicle are taken as reference wheels is adopted for the left or right entity wheels of the ith axle.
7. The wheel slip ratio calculation method according to claim 6, characterized in that the real-time slip ratio of the wheel in step S3 is calculated by the formula (13):
wherein: s is S ij Slip ratio of the solid wheel on the left side or the right side of the ith axle; beta is the vehicle systemA dynamic or driven state; v (V) ij The translation speed of the center of the wheel of the entity on the left or right side of the ith axle, calculated on the basis of the wheel speed, is equal to V kt Essentially a variable, numbered differently; v1 is a closing speed threshold value of dynamic calculation of the slip rate; v2 is a dynamically calculated opening speed threshold, and V2 is greater than V1; v2 and V1 are calibratable modification parameters;
If the vehicle is in a braking state and the wheel rotation speed in an unlocked state is maximum, vmax ij Effectively, the value of beta is 1;
if the vehicle is in a driving state and the wheel rotation speed is minimum in a non-slip state, vmin ij Effectively, the value of beta is-1.
8. A wheel slip ratio calculation apparatus, comprising:
the first calculation module is used for calculating absolute speeds of the solid wheels relative to the reference wheels on the reference axle in the directions of the vehicle body X and the vehicle body Y according to the partial speeds of the translation speed of the center of the reference wheels on the reference axle in the directions of the vehicle body X and the vehicle body Y and the partial speeds of the relative linear speeds of the solid wheels relative to the reference wheels on the reference axle in the directions of the vehicle body X and the vehicle body Y caused by the rotation motion of the rigid bodies;
the second calculation module calculates the maximum value and the minimum value of the absolute speed of the solid wheel relative to the reference wheel on the reference axle in the rotating direction and the absolute speed of the solid wheel relative to the reference wheels on all the reference axles in the rotating direction according to the absolute speeds of the solid wheel relative to the reference wheels on the reference axle in the vehicle body X direction and the vehicle body Y direction;
and the third calculation module is used for calculating the real-time slip rate of the wheels according to the translation speed of the center of the entity wheel and the maximum value and the minimum value of the absolute speeds of the entity wheel relative to the reference wheels on all the reference axles in the rotating direction.
9. An electronic device comprising a processor and a memory, the processor and the memory being interconnected;
the memory is used for storing a computer program;
the processor is configured to execute the wheel slip ratio calculation method according to any one of claims 1 to 6 when the computer program is invoked.
10. A computer-readable storage medium, characterized in that the computer-readable storage medium stores a computer program that is executed by a processor to implement the wheel slip ratio calculation method according to any one of claims 1 to 6.
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