A method for measuring lateral deviation of a rubber-tyred low-floor virtual track train

Abstract

The present invention discloses a method for measuring the lateral deviation of a rubber-tyred low-floor virtual track train vehicle, the method comprising the following steps: measuring the displacement of the EMU bogie rod system and the displacement of the workshop articulated steering rod system of the rubber-tyred vehicle respectively through pre-configured sensors; measuring the wheel angle, and establishing a numerical relationship between the displacement of the EMU bogie rod system and the wheel angle; measuring the workshop articulation angle, and establishing a numerical relationship between the displacement of the workshop articulated steering rod system and the workshop articulation angle; calculating the difference between the actual offset of the vehicle and the theoretical optimal offset, and obtaining the lateral deviation value of the vehicle. Based on the structural characteristics of the train bogie, the present invention can meet the demand for accurate measurement of lateral deviations in the initial stage of virtual train commissioning, the method has reliable calculation results, and can fully achieve the purpose of improving commissioning efficiency and tracking control accuracy, and can also greatly reduce abnormal wheel wear.

Description

Technical Field

[0001] The present invention relates to the field of rail transportation, and in particular to a method for measuring the lateral deviation of a rubber-tyred low-floor virtual track train. Background Art

[0002] The virtual rail transit system is a road transportation system that adopts the urban rail transit operation and management model. The so-called "virtual track" is different from the physical track used in the traditional railway transportation system. It is a new type of "digital track" formed by adding a series of ground sensing devices or beacons to the traditional urban roads. The virtual rail train adopts non-contact guidance technology and rubber wheel running gear, and uses environmental perception technology to identify and perceive virtual track information and train operation environment, uses information fusion technology to achieve high-precision vehicle positioning, and realizes train self-guidance through tracking control technology. Therefore, the virtual rail train has the advantages of large capacity and high running stability of traditional trams, as well as strong adaptability of buses and BRT (Bus Rapid Transit System) and low road construction cost.

[0003] The rubber-tyred low-floor virtual rail vehicle adopts a bogie structure with all-axle steering, and each bogie has independent steering control capabilities. This feature poses a great challenge to the train tracking control, so a lot of control adjustments need to be made before formal operation so that the train tracking can reach the optimal state. How to accurately measure the lateral deviation of the train in the early stage of virtual rail train commissioning has become one of the topics that professionals need to study.

[0004] Due to the constraints of wheels and rails, the lateral deviations between the vehicles of traditional steel wheel and steel rail standard trains and the lateral deviations of the vehicles from the center line of the track will not be very large, which will not cause the vehicle limit to expand infinitely and greatly reduce the civil engineering cost of rail transit. During the initial vehicle commissioning of the rubber wheel low-floor virtual track train, because the tracking control logic of the virtual track train has not yet matched the actual state of the vehicle, and there is no wheel and rail constraint, every time you pass a curve, you have to get off the train to check the lateral deviation of each vehicle in the train, and then adjust the tracking control parameters, and repeat the cycle until the lateral deviation between each vehicle and the virtual track is visually considered to be the smallest. This will make it possible for the train to intrude into the limit, causing interference, and seriously causing vehicle driving safety risks. This method is greatly affected by human factors and has a low degree of intelligence. The vehicle control parameter adjustment process is greatly affected by the subjective judgment of technicians, which will cause serious excessive lateral deviation during train operation and cause rapid tire wear.

[0005] To sum up, how to develop a method for accurately measuring the lateral deviation of virtual track trains, avoid relying on the experience of technicians, improve the intelligence level of virtual track train control parameter debugging, greatly reduce tire wear, and save maintenance costs has become one of the problems that technical personnel in this field urgently need to solve. Summary of the invention

[0006] In view of the problems in the related art, the present invention proposes a method for measuring the lateral deviation of a rubber-tyred low-floor virtual track train vehicle to overcome the above technical problems existing in the existing related art.

[0007] To this end, the specific technical solution adopted by the present invention is as follows:

[0008] A method for measuring the lateral deviation of a rubber-tyred low-floor virtual track train, the method comprising the following steps:

[0009] The displacement of the bogie rod system of the rubber-tyred vehicle and the displacement of the articulated steering rod system of the workshop are measured respectively by using pre-configured sensors;

[0010] Measure the wheel angle and establish the numerical relationship between the displacement of the EMU bogie rod system and the wheel angle;

[0011] The workshop articulation angle is measured, and the numerical relationship between the displacement of the workshop articulated steering linkage and the workshop articulation angle is established;

[0012] The difference between the actual offset of the vehicle and the theoretical optimal offset is calculated to obtain the lateral deviation value of the vehicle.

[0013] Furthermore, the step of measuring the wheel angle further comprises the following steps:

[0014] The wheel steering mechanism is set as a four-bar linkage;

[0015] Based on the geometric relationship of the four-bar linkage, two measuring points are set on the connecting rod, and the wheel angle is converted through the displacement between the two measuring points.

[0016] Furthermore, the method of setting two measuring points on the connecting rod based on the geometric relationship of the four-bar linkage and converting the wheel angle by the displacement between the two measuring points also includes the following steps:

[0017] Assume that the four-bar linkage consists of connecting rods AB, BC, CD and AD, and establish a coordinate system XAY. Each bar system is represented by a vector. The complex form of the closed vector equation of the structure is:

[0018]

[0019] In the formula, is the angle between connecting rod AB and X axis;

[0020] is the angle between the connecting rod BC and the X-axis;

[0021] is the angle between the connecting rod CD and the X-axis;

[0022] l1 is the length of connecting rod AB, l2 is the length of connecting rod BC, l3 is the length of connecting rod CD, and l4 is the length of connecting rod AD;

[0023] It is the exponential expression of complex numbers;

[0024] i is the imaginary unit of the complex number, and

[0025] i 2 = -1;

[0026] Apply Euler's formula:

[0027] e iθ =cosθ+isinθ

[0028] Separating the real and imaginary parts of Euler's formula, we get:

[0029]

[0030] The formula after separation of the real part and the imaginary part is obtained:

[0031]

[0032] By eliminating And get:

[0033]

[0034] in,

[0035]

[0036] C=(A 2 +B 2 +l32-l22) / 2l3;

[0037] Request for removal Get and

[0038] In the formula, is the angle between connecting rod AB and X axis;

[0039] is the angle between the connecting rod BC and the X-axis;

[0040] is the angle between the connecting rod CD and the X-axis;

[0041] l1 is the length of connecting rod AB, l2 is the length of connecting rod BC, l3 is the length of connecting rod CD, and l4 is the length of connecting rod AD;

[0042] θ is the angle;

[0043] Reference points E and G are set on connecting rod AB, and reference points F and H are set on connecting rod AD. The distance between point E and point F is measured by a displacement sensor, and the theoretical formula can be reversed to obtain:

[0044]

[0045] x F =f

[0046] y F =t1;

[0047] In the formula, is the angle between connecting rod AB and X axis;

[0048] l1 is the length of connecting rod AB, l5 is the length of connecting rod AE;

[0049] l EF is the length between two points EF;

[0050] f is the distance between AH;

[0051] t1 is the distance between FH;

[0052] t2 is the distance between GEs;

[0053] e is the distance between BG.

[0054] Furthermore, when measuring the articulation angle of the workshop, the carriages of the rubber-tyred vehicle are connected by an articulation mechanism, and two test points are set on the articulation mechanism, and the rotation angle is converted by the displacement between the two test points.

[0055] Furthermore, the measuring of the workshop articulation angle further comprises the following steps:

[0056] When the rubber-wheeled vehicle is in the initial position on the straight line,

[0057] α0=arctan(b0 / (L0 / 2))

[0058] Where, α0 is the initial angle when the installation test point is a straight line;

[0059] b0 is the distance between the installation test point A and the center of the vehicle;

[0060] L0 is the initial distance between the two test points when they are in a straight line AB;

[0061] When the rubber-tyred vehicle turns to any position, the workshop articulation angle is calculated.

[0062] Furthermore, the calculation formula of the workshop articulation angle is:

[0063]

[0064] Where, α0 is the initial angle when the installation test point is a straight line;

[0065] b0 is the distance between the installation test point A and the center of the vehicle;

[0066] L0 is the initial distance between the two test points when they are in a straight line AB;

[0067] α represents the articulation angle between the two vehicles;

[0068] △L is the distance between the two test points AB relative to the straight line due to passing through the curve.

[0069] Furthermore, the theoretical optimal offset is obtained based on the kinematic geometric relationship when the rubber-tyred vehicle passes through a circular curve in an ideal posture;

[0070] Set the 1st axis, i.e. the direction of wheel movement, as the X-axis, the vertical direction of the X-axis as the Y-axis and establish a reference coordinate system, and the reference coordinate system also includes the 2nd axis, the 3rd axis, the 4th axis, the 5th axis, the 6th axis, the 7th axis and the 8th axis;

[0071] The projection of the centers of axes 1-8 and the center point of the workshop articulation on the Y axis of the reference coordinate system is used as the lateral offset indicator;

[0072] The radius of the circular curve is R, and the ideal hinge angle is obtained.

[0073] Furthermore, the method of obtaining an ideal articulation angle further comprises the following steps:

[0074] The ideal 1-axle wheel steering angle is:

[0075]

[0076] Where L1 is the distance between the center of axis 1 and the center of the hinge point between axis 3 and axis 4;

[0077] R is the radius of the circular curve;

[0078] The ideal articulation angle is:

[0079]

[0080] Where L3 is the distance between the hinge point between axis 3 and axis 4 and the hinge point between axis 5 and axis 6;

[0081] L1 is the distance between the center of axis 1 and the center of the hinge point between axis 3 and axis 4;

[0082] Calculate the theoretically optimal offset.

[0083] Furthermore, when calculating the actual offset of the vehicle, the displacement of the measuring point of the four-bar linkage and the distance of the measuring point of the hinge position are measured, and the wheel angle obtained by calculation is used. The calculation formula of articulation angle α(j) and lateral offset is:

[0084]

[0085] The actual lateral offset Y(j) of the vehicle is calculated;

[0086] In the formula, is the ideal lateral offset of the 5-axis relative to the Y-axis in the reference coordinate system;

[0087] L2 is the distance between the center of axis 5 and the hinge point between axis 3 and axis 4;

[0088] The ideal articulation angle for the articulation point between axis 3 and axis 4;

[0089] The ideal steering angle of the wheels on axle 1;

[0090] y h1 The ideal lateral offset of the hinge point between axis 3 and axis 4 relative to the Y axis in the reference coordinate system;

[0091] L1 is the distance between the center of axis 1 and the hinge point between axis 3 and axis 4.

[0092] Furthermore, the calculation formula of the vehicle lateral deviation value is:

[0093]

[0094] Where △Y is the lateral deviation of the vehicle;

[0095] Y(j) is the actual lateral offset of the vehicle;

[0096] is the ideal lateral offset;

[0097] j is the serial number of each axis or each hinge point.

[0098] The beneficial effects of the present invention are:

[0099] (1) Based on the structural characteristics of the train bogie, the present invention can meet the needs of accurate measurement of lateral deviation in the initial stage of virtual train commissioning. The calculation results of the method are reliable, and the purpose of improving commissioning efficiency and tracking control accuracy can be fully achieved. At the same time, it can also greatly reduce abnormal wear of wheels. It has the advantages of improving commissioning efficiency, tracking control accuracy and reducing wheel wear.

[0100] (2) Based on the structural characteristics of the bogie of the low-floor virtual track train with rubber wheels, the present invention uses displacement sensors to measure the displacement of the rod system, converts it into wheel angle and workshop angle, considers the motion geometry relationship when the virtual track train passes through a circular curve in an ideal posture, obtains the lateral deviation value between the actual offset and the theoretical optimal offset, and uses it as an indicator for evaluating the vehicle tracking deviation during the initial vehicle commissioning of the virtual track train. This greatly improves the efficiency of the control parameter calibration work of the low-floor virtual track train with rubber wheels, reduces the errors caused by human factors, improves the control accuracy and reliability of the virtual track train, and reduces unnecessary wear of the wheels. BRIEF DESCRIPTION OF THE DRAWINGS

[0101] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0102] Figure 1 is a flow chart of a method for measuring lateral deviation of a rubber-tyred low-floor virtual track train according to an embodiment of the present invention;

[0103] Figure 2 is a schematic diagram of the steering mechanism;

[0104] Figure 3 It is a schematic diagram of the workshop articulation geometry;

[0105] Figure 4 It is a schematic diagram of the lateral offset of the train when turning;

[0106] Figure 5 It is a schematic diagram of train formation;

[0107] Figure 6 It is a test circuit diagram;

[0108] Figure 7 is a schematic diagram of the articulation angle;

[0109] Figure 8 It is a schematic diagram of the steering angles of the 1st, 4th and 6th axes;

[0110] Fig. 9 This is a schematic diagram of the theoretical optimal offset result of axis 1;

[0111] Fig.10 This is a schematic diagram of the theoretical optimal offset results of the 4-axis;

[0112] Fig.11 This is a schematic diagram of the theoretical optimal offset results of the 6-axis;

[0113] Fig.12 It is a schematic diagram of the lateral offset result of the hinge point of the front workshop;

[0114] Fig.13 It is a schematic diagram of the lateral offset results of the hinge point of the rear workshop. DETAILED DESCRIPTION

[0115] To further illustrate each embodiment, the present invention provides drawings, which are part of the disclosure of the present invention and are mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these contents, ordinary technicians in the field should be able to understand other possible implementations and advantages of the present invention. The components in the figures are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0116] According to an embodiment of the present invention, a method for measuring the lateral deviation of a rubber-tyred low-floor virtual track train is provided.

[0117] The present invention is further described with reference to the accompanying drawings and specific embodiments. Figure 1 As shown, according to the method for measuring the lateral deviation of a rubber-tyred low-floor virtual track train vehicle according to an embodiment of the present invention, the method comprises the following steps:

[0118] The displacement of the bogie rod system of the rubber-tyred vehicle and the displacement of the articulated steering rod system of the workshop are measured respectively by using pre-configured sensors;

[0119] Measure the wheel angle and establish the numerical relationship between the displacement of the EMU bogie rod system and the wheel angle;

[0120] In one embodiment, the measuring of the wheel angle further comprises the following steps:

[0121] The wheel steering mechanism is simplified and set as a four-bar linkage;

[0122] Based on the geometric relationship of the four-bar linkage, two measuring points are set on the connecting rod, and the wheel angle is converted through the displacement between the two measuring points.

[0123] In one embodiment, the method of setting two measuring points on the connecting rod based on the geometric relationship of the four-bar linkage and converting the wheel angle by the displacement between the two measuring points further includes the following steps:

[0124] according to Figure 2 As shown in the schematic diagram of the steering mechanism, the four-bar linkage is assumed to consist of connecting rods AB, BC, CD and AD, and a coordinate system XAY is established. Each bar system is represented by a vector, and the complex form of the closed vector equation of the structure is:

[0125]

[0126] In the formula, is the angle between connecting rod AB and X axis;

[0127] is the angle between the connecting rod BC and the X-axis;

[0128] is the angle between connecting rod CD and X axis, and and It is not fixed, but changes as the vehicle turns;

[0129] l1 is the length of connecting rod AB, l2 is the length of connecting rod BC, l3 is the length of connecting rod CD, and l4 is the length of connecting rod AD; l1, l2, l3 and l4 can be directly measured;

[0130] It is the exponential expression of complex numbers;

[0131] i is the imaginary unit of the complex number, and

[0132] i 2 = -1;

[0133] Apply Euler's formula:

[0134] e iθ =cosθ+isinθ

[0135] Separating the real and imaginary parts of Euler's formula, we can obtain from formula (2):

[0136]

[0137] The formula after separation of the real part and the imaginary part is obtained:

[0138]

[0139] By eliminating The square of formula (3) plus the square of formula (4) gives:

[0140]

[0141] in,

[0142]

[0143] Request for removal Get and

[0144] In the formula, is the angle between connecting rod AB and X axis;

[0145] is the angle between the connecting rod BC and the X-axis;

[0146] is the angle between the connecting rod CD and the X-axis;

[0147] l1 is the length of connecting rod AB, l2 is the length of connecting rod BC, l3 is the length of connecting rod CD, and l4 is the length of connecting rod AD;

[0148] θ is the angle;

[0149] Reference points E and G are set on connecting rod AB, and reference points F and H are set on connecting rod AD, respectively. The distance between point E and point F is measured by a displacement sensor. From the geometric relationship in the four-bar linkage, it can be seen that the measuring point E in the coordinate system XAY changes with the wheel angle. The distance between points EF is measured by the displacement sensor, and the theoretical formula can be reversed to obtain:

[0150]

[0151] x F =f(11)

[0152] y F =t1; (12)

[0153] In the formula, is the angle between connecting rod AB and X axis;

[0154] l1 is the length of connecting rod AB, l5 is the length of connecting rod AE;

[0155] l EF is the length between two points EF, i.e., the angle between the wheels Function, which can be directly obtained by displacement sensor measurement;

[0156] f is the distance between AH in the figure, which has a fixed value and can be measured directly;

[0157] t1 is the distance between FH in the figure, which has a fixed value and can be directly measured;

[0158] t2 is the distance between GEs in the figure, which has a fixed value and can be directly measured;

[0159] e is the distance between BG in the figure, which has a fixed value and can be measured directly.

[0160] The workshop articulation angle is measured, and the numerical relationship between the displacement of the workshop articulated steering linkage and the workshop articulation angle is established;

[0161] In one embodiment, when measuring the articulation angle of the workshop, the carriages of the rubber-tyred vehicle are connected by an articulation mechanism, and two test points are set on the articulation mechanism, and the rotation angle is converted by the displacement between the two test points.

[0162] In one embodiment, the measuring of the workshop articulation angle further comprises the following steps:

[0163] like Figure 3 As shown, when the rubber-wheeled vehicle is at the initial position on the straight line,

[0164] α0=arctan(b0 / (L0 / 2)) (13)

[0165] Where, α0 is the initial angle when the installation test point is a straight line;

[0166] b0 is the distance between the installation test point A and the center of the vehicle;

[0167] L0 is the initial distance between the two test points AB, which is a fixed value and can be directly measured;

[0168] When the rubber-tyred vehicle turns to any position, the workshop articulation angle is calculated.

[0169] In one embodiment, the calculation formula of the workshop articulation angle is:

[0170]

[0171] Where, α0 is the initial angle when the installation test point is a straight line;

[0172] b0 is the distance between the installation test point A and the center of the vehicle;

[0173] L0 is the initial distance between the two test points when they are in a straight line AB;

[0174] α represents the articulation angle between the two vehicles;

[0175] △L is the distance between two test points AB relative to the straight line due to passing through the curve, which can be measured by the sensor.

[0176] Calculate the difference between the actual offset of the vehicle and the theoretical optimal offset to obtain the lateral deviation value of the vehicle;

[0177] In one embodiment, the theoretical optimal offset is obtained based on the kinematic geometry of the rubber-tyred vehicle when it passes through a circular curve in an ideal posture; (the theoretical optimal offset is obtained based on the kinematic geometry of the train when it passes through a circular curve in an ideal posture)

[0178] like Figure 4 As shown, set the 1st axis, that is, the direction of wheel movement, as the X-axis, the vertical direction of the X-axis as the Y-axis and establish a reference coordinate system, and the reference coordinate system also includes the 2nd axis, the 3rd axis, the 4th axis, the 5th axis, the 6th axis, the 7th axis and the 8th axis;

[0179] Among them, axles 1-8 refer to the axles under the train, and the number of axles of the train can be more than 8 or less than 8.

[0180] The projection of the centers of axes 1-8 and the center point of the workshop articulation on the Y axis of the reference coordinate system is used as the lateral offset indicator;

[0181] Among them, the lateral offset under the ideal state (the situation where the axle bridges at both ends and the two workshop articulation center points are on the circular curve is regarded as the ideal tracking state) needs to be obtained according to the vehicle structure size parameters, the ideal wheel turning angle and the ideal articulation angle;

[0182] The radius of the circular curve is R, and the ideal articulation angle is obtained (the ideal wheel turning angle and the ideal articulation angle can be calculated analytically).

[0183] In one embodiment, obtaining the ideal articulation angle further comprises the following steps:

[0184] The ideal 1-axle wheel steering angle is:

[0185]

[0186] Where L1 is the distance between the center of axis 1 and the center of the hinge point between axis 3 and axis 4, which is a fixed value that can be directly measured;

[0187] R is the radius of the circular curve;

[0188] The ideal articulation angle is:

[0189]

[0190] Where L3 is the distance between the hinge point between axis 3 and axis 4 and the hinge point between axis 5 and axis 6, which is a fixed value and can be directly measured;

[0191] L1 is the distance between the center of axis 1 and the center of the hinge point between axis 3 and axis 4

[0192] Calculate the theoretically optimal offset.

[0193] In one embodiment, when calculating the theoretical optimal offset, taking the 5-axis as an example, the ideal lateral offset can be calculated as:

[0194]

[0195] The actual lateral offset Y(j) of the vehicle is calculated;

[0196] In the formula, For 5 axes in ( Figure 4 ) is the ideal lateral offset relative to the Y axis in the reference coordinate system;

[0197] L2 is the distance between the center of axis 5 and the hinge point between axis 3 and axis 4;

[0198] The ideal articulation angle for the articulation point between axis 3 and axis 4;

[0199] The ideal steering angle of the wheels on axle 1;

[0200] y h1 The hinge point between axis 3 and axis 4 is ( Figure 4 ) is the ideal lateral offset relative to the Y axis in the reference coordinate system;

[0201] L1 is the distance between the center of axis 1 and the center of the hinge point between axis 3 and axis 4. The ideal lateral offset of the remaining positions can be calculated using the above 5-axis calculation method.

[0202] In one embodiment, when calculating the actual offset of the vehicle, each position is measured to obtain the displacement of the measuring point of the four-bar linkage and the distance of the measuring point of the hinge position, and the wheel angle is calculated. (Formula 1-12), articulation angle α(j) (Formula 13-14) and lateral offset calculation formula:

[0203]

[0204] The actual lateral offset Y(j) of the vehicle is calculated;

[0205] In the formula, For 5 axes in ( Figure 4 ) is the ideal lateral offset relative to the Y axis in the reference coordinate system;

[0206] L2 is the distance between the center of axis 5 and the hinge point between axis 3 and axis 4. It is a fixed value and can be measured directly.

[0207] The ideal articulation angle for the articulation point between axis 3 and axis 4;

[0208] The ideal steering angle of the wheels on axle 1;

[0209] y h1 The hinge point between axis 3 and axis 4 is ( Figure 4 ) is the ideal lateral offset relative to the Y axis in the reference coordinate system;

[0210] L1 is the distance between the center of axis 1 and the hinge point between axis 3 and axis 4. It is a fixed value and can be measured directly.

[0211] In one embodiment, the calculation formula of the vehicle lateral deviation value is:

[0212]

[0213] Where △Y is the lateral deviation of the vehicle;

[0214] Y(j) is the actual lateral displacement of the vehicle at each axle or each hinge point;

[0215] is the ideal lateral offset;

[0216] j is the serial number of each axis or each hinge point.

[0217] In one embodiment, a three-carriage rubber-wheeled train Figure 5 As shown, in a real line such as Figure 6 During the period, according to the steering mechanism and articulation mechanism of the rubber-tyred train, the method for determining the lateral deviation of the rubber-tyred low-floor virtual track train according to the present invention obtains the workshop articulation angle as shown in FIG. Figure 7 As shown and the wheel steering angle as Figure 8 As shown;

[0218] like Figure 9-13 The lateral offset of the vehicle is converted based on the measured steering angle and articulation angle, and then compared with the theoretical lateral offset of the vehicle to obtain the lateral deviation of the train passing through the line.

[0219] In summary, the present invention is based on the structural characteristics of the train bogie, and can meet the needs of accurate measurement of lateral deviations in the initial stage of virtual train commissioning. The calculation results of the method are reliable, and the purpose of improving commissioning efficiency and tracking control accuracy can be fully achieved. At the same time, the abnormal wear of the wheels can also be greatly reduced. It has the advantages of improving commissioning efficiency, tracking control accuracy and reducing wheel wear. Based on the structural characteristics of the bogie of a low-floor rubber-tyred virtual track train, the present invention uses a displacement sensor to measure the displacement of the rod system, converts it to the wheel angle and the workshop angle, considers the motion geometry relationship when the virtual track train passes through a circular curve in an ideal posture, and obtains the lateral deviation value between the actual offset and the theoretical optimal offset, which is used as an indicator for evaluating the vehicle tracking deviation during the initial vehicle commissioning of the virtual track train. In this way, the efficiency of the control parameter calibration work of the low-floor rubber-tyred virtual track train is greatly improved, the errors caused by human factors are reduced, the control accuracy and reliability of the virtual track train are improved, and unnecessary wear of the wheels is reduced.

[0220] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for measuring the lateral deviation of a rubber-tyred low-floor virtual track train, characterized in that: The method comprises the following steps: The displacement of the bogie rod system of the rubber-tyred vehicle and the displacement of the articulated steering rod system of the workshop are measured respectively by using pre-configured sensors; Measure the wheel angle and establish the numerical relationship between the displacement of the EMU bogie rod system and the wheel angle; The workshop articulation angle is measured, and the numerical relationship between the displacement of the workshop articulated steering linkage and the workshop articulation angle is established; Calculate the difference between the actual offset of the vehicle and the theoretical optimal offset to obtain the lateral deviation value of the vehicle; specifically include: The theoretical optimal offset is obtained based on the kinematic geometry of the rubber-tyred vehicle passing through a circular curve in an ideal posture; Set the 1st axis, i.e. the direction of wheel movement, as the X-axis, the vertical direction of the X-axis as the Y-axis and establish a reference coordinate system, and the reference coordinate system also includes the 2nd axis, the 3rd axis, the 4th axis, the 5th axis, the 6th axis, the 7th axis and the 8th axis; The projection of the centers of axes 1-8 and the center point of the workshop articulation on the Y axis of the reference coordinate system is used as the lateral offset indicator; Get the radius of the circular curve as R and find the ideal hinge angle; The ideal 1-axle wheel steering angle is: The ideal articulation angle is: Calculate the theoretical optimal offset; When calculating the actual vehicle offset, the displacement of the measuring point of the four-bar linkage and the distance of the test point at the hinge position are measured, and the wheel angle is calculated. The calculation formula of articulation angle α(j) and lateral offset is: The actual lateral offset Y(j) of the vehicle is calculated; Where L1 is the distance between the center of axis 1 and the center of the hinge point between axis 3 and axis 4; R is the radius of the circular curve; L3 is the distance between the hinge point between axis 3 and axis 4 and the hinge point between axis 5 and axis 6; is the ideal lateral offset of the 5-axis relative to the Y-axis in the reference coordinate system; L2 is the distance between the center of axis 5 and the hinge point between axis 3 and axis 4; The ideal articulation angle for the articulation point between axis 3 and axis 4; The ideal steering angle of the wheels on axle 1; y h1 The ideal lateral offset of the hinge point between axis 3 and axis 4 relative to the Y axis in the reference coordinate system; L1 is the distance between the center of axis 1 and the hinge point between axis 3 and axis 4.

2. The method for measuring the lateral deviation of a rubber-tyred low-floor virtual track train according to claim 1 is characterized in that: The wheel angle measurement also includes the following steps: The wheel steering mechanism is set as a four-bar linkage; Based on the geometric relationship of the four-bar linkage, two measuring points are set on the connecting rod, and the wheel angle is converted through the displacement between the two measuring points.

3. The method for measuring the lateral deviation of a rubber-tyred low-floor virtual track train according to claim 2 is characterized in that: The method of setting two measuring points on the connecting rod based on the geometric relationship of the four-bar linkage and converting the wheel angle by the displacement between the two measuring points also includes the following steps: Assume that the four-bar linkage consists of connecting rods AB, BC, CD and AD, and establish a coordinate system XAY. Each bar system is represented by a vector. The complex form of the closed vector equation of the structure is: In the formula, is the angle between connecting rod AB and X-axis; is the angle between the connecting rod BC and the X-axis; is the angle between the connecting rod CD and the X-axis; l1 is the length of connecting rod AB, l2 is the length of connecting rod BC, l3 is the length of connecting rod CD, and l4 is the length of connecting rod AD; is the exponential expression of a complex number; i is the imaginary unit of the complex number, and i 2 ＝-1； Apply Euler's formula: And iθ =cosθ+isinθ Separating the real and imaginary parts of Euler's formula, we get: The formula after separation of the real part and the imaginary part is obtained: By eliminating And get: in, Request for removal Get and In the formula, is the angle between connecting rod AB and X-axis; is the angle between the connecting rod BC and the X-axis; is the angle between the connecting rod CD and the X-axis; l1 is the length of connecting rod AB, l2 is the length of connecting rod BC, l3 is the length of connecting rod CD, and l4 is the length of connecting rod AD; θ is the angle; Reference points E and G are set on connecting rod AB, and reference points F and H are set on connecting rod AD. The distance between point E and point F is measured by a displacement sensor, and the theoretical formula can be reversed to obtain: x F =f y F =t1; In the formula, is the angle between connecting rod AB and X-axis; l1 is the length of connecting rod AB, l5 is the length of connecting rod AE; l EF is the length between two points EF; f is the distance between AH; t1 is the distance between FH; t2 is the distance between GEs; e is the distance between BG.

4. The method for measuring the lateral deviation of a rubber-tyred low-floor virtual track train according to claim 1 is characterized in that: When measuring the articulation angle of the workshop, the carriages of the rubber-tyred vehicle are connected by an articulation mechanism, and two test points are set on the articulation mechanism, and the rotation angle is converted by the displacement between the two test points.

5. The method for measuring the lateral deviation of a rubber-tyred low-floor virtual track train according to claim 4 is characterized in that: The measuring of the workshop articulation angle also includes the following steps: When the rubber-wheeled vehicle is in the initial position on the straight line, α0=arc tan(b0 / (L0 / 2)) Where, α0 is the initial angle when the installation test point is a straight line; b0 is the distance between the installation test point A and the center of the vehicle; L0 is the initial distance between the two test points when they are in a straight line AB; When the rubber-tyred vehicle turns to any position, the workshop articulation angle is calculated.

6. The method for measuring the lateral deviation of a rubber-tyred low-floor virtual track train according to claim 5 is characterized in that: The calculation formula of the workshop articulation angle is: Where, α0 is the initial angle when the installation test point is a straight line; b0 is the distance between the installation test point A and the center of the vehicle; L0 is the initial distance between the two test points when they are in a straight line AB; α represents the articulation angle between the two vehicles; △L is the distance between the two test points AB relative to the straight line due to passing through the curve.

7. The method for measuring the lateral deviation of a rubber-tyred low-floor virtual track train according to claim 1 is characterized in that: The calculation formula of the vehicle lateral deviation value is: Where △Y is the lateral deviation of the vehicle; Y(j) is the actual lateral offset of the vehicle; is the ideal lateral offset; j is the serial number of each axis or each hinge point.

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