A bicycle trajectory tracking sliding mode control method and system

Abstract

The present application relates to the technical field of automation control, and more particularly to a bicycle trajectory tracking sliding mode control method and system. The method comprises the following steps: S1: obtaining bicycle obstacle avoidance data, bicycle pedal pressure data and saddle pressure data on a downhill section; S2: determining a bicycle obstacle avoidance success coefficient and generating a bicycle trajectory tracking route; S3: calculating a sliding mode control coefficient according to the bicycle pedal pressure data and the saddle pressure data; and S4: determining a bicycle trajectory tracking sliding mode control method based on the bicycle obstacle avoidance success coefficient and the sliding mode control coefficient. The present application collects obstacle avoidance, pedal and saddle pressure data, accurately calculates an obstacle avoidance coefficient, dynamically adjusts control parameters, optimizes trajectory tracking, greatly improves the safety and comfort of downhill riding, and flexibly responds to real-time data through an adaptive control system, enhances riding comfort, improves data utilization efficiency, and realizes efficient and intelligent operation.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of automation control technology, in particular to a bicycle trajectory tracking sliding mode control method and system. BACKGROUND

[0002] With the increasing global attention on sustainable transportation, bicycles are gaining more and more attention as an environmentally friendly and healthy travel option. However, in complex road environments, especially on downhill sections, cyclists face challenges such as obstacle avoidance and maintaining a stable trajectory. Traditional manual control is difficult to ensure safe and effective response to these challenges in all situations, especially at high speeds or in complex environments. Therefore, it is particularly urgent to develop an intelligent control system that can automatically optimize the bicycle's travel path and improve its obstacle avoidance ability.

[0003] In recent years, the development of automation control theory and technology has provided new possibilities for solving the above problems. Sliding mode control, as an efficient nonlinear control method, is widely used in the control of various dynamic systems due to its good robustness and fast response characteristics. At the same time, the progress of sensor technology makes it possible to collect and process vehicle motion data in real time, which lays the foundation for further intelligent bicycle control. SUMMARY

[0004] In order to overcome the shortcomings, the technical problem to be solved is to provide a bicycle trajectory tracking sliding mode control method and system.

[0005] The technical scheme of the present application is: a bicycle trajectory tracking sliding mode control method, comprising the following steps:

[0006] S1: on a downhill section, acquiring bicycle obstacle avoidance data, bicycle pedal pressure data and saddle pressure data;

[0007] S2: determining a bicycle obstacle avoidance success coefficient and generating a bicycle trajectory tracking route;

[0008] S3: calculating a sliding mode control coefficient based on the bicycle pedal pressure data and the saddle pressure data;

[0009] S4: determining a bicycle trajectory tracking sliding mode control method based on the bicycle obstacle avoidance success coefficient and the sliding mode control coefficient.

[0010] Preferably, the bicycle obstacle avoidance data, bicycle pedal pressure data and saddle pressure data are acquired on the downhill section, comprising:

[0011] The obstacle avoidance data refers to the speed data before and after the bicycle avoids obstacles;

[0012] The bicycle pedal pressure data refers to the pedal pressure data before the bicycle avoids the barrier;

[0013] The bicycle seat pressure data refers to the seat pressure data after the bicycle avoids the barrier;

[0014] The intervention speed of the bicycle skid before avoiding the barrier and the intervention speed after avoiding the barrier are collected;

[0015] Based on the barrier avoidance data, the bicycle pedal pressure data, the bicycle seat pressure data, and the bicycle skid intervention speed, the related parameters of the bicycle barrier avoidance calculation formula are calculated, and the related parameters include a first allocation speed, a second allocation speed, a first pressure, and a second pressure.

[0016] Preferably, the calculation of the related parameters of the bicycle barrier avoidance calculation formula includes:

[0017] The speed before the bicycle avoids the barrier minus the speed before the skid intervention is taken as the first allocation speed;

[0018] The speed after the bicycle avoids the barrier minus the speed after the skid intervention is taken as the second allocation speed;

[0019] The pedal pressure minus the pedal pressure after the skid intervention is taken as the first pressure;

[0020] The seat pressure minus the seat pressure after the skid intervention is taken as the second pressure;

[0021] The first allocation speed, the second allocation speed, the first pressure, and the second pressure are normalized by a normalization formula.

[0022] Preferably, the normalization of the first allocation speed, the second allocation speed, the first pressure, and the second pressure by the normalization formula includes that the normalization formula is as follows,

[0023]

[0024] Wherein, x min and x max are the minimum and maximum values of the variable, respectively.

[0025] Preferably, the determination of the bicycle barrier avoidance success coefficient and the generation of the bicycle trajectory tracking route include that the bicycle barrier avoidance success coefficient is determined by the bicycle barrier avoidance calculation formula, and the bicycle trajectory tracking route is generated based on the bicycle barrier avoidance success coefficient, and the bicycle barrier avoidance calculation formula is as follows,

[0026]

[0027] Wherein, C success is the bicycle barrier avoidance success coefficient, V first-norm and V second-normrespectively, normalized first and second delivery velocities, P pedal-first-norm and P seat-second-norm respectively, normalized first and second pressures, ∈ is a minimum value; normalized first delivery velocity V first-norm = V pre -V control , normalized second delivery velocity V second-norm = V post -V control , normalized first pressure P pedal-first-norm = P pedal,pre -P pedal,control , normalized second pressure P seat-second-norm = P seat,post -P seat,control .

[0028] Preferably, the generating the bicycle trajectory tracking route comprises:

[0029] Based on the bicycle obstacle avoidance success coefficient, set the obstacle avoidance qualified threshold T, if C success is greater than or equal to T, the obstacle avoidance is successful; otherwise, the obstacle avoidance fails;

[0030] Obtain the original trajectory tracking route of the bicycle, and mark the obstacle avoidance failure section;

[0031] The obstacle avoidance failure section is marked by the obstacle avoidance section marking formula, and the obstacle avoidance section marking formula is as follows,

[0032]

[0033] Wherein, D is the starting marking distance of the obstacle avoidance failure section, L prev is the position of the successful obstacle avoidance section, L fail is the next obstacle avoidance failure section position adjacent to the successful obstacle avoidance section position, norm() is a normalization function, m is the failure obstacle avoidance section marking number of the next obstacle avoidance failure section adjacent to the successful obstacle avoidance section position, is the average value of the failure obstacle avoidance section marking numbers of all next obstacle avoidance failure sections adjacent to the successful obstacle avoidance section position in the whole section, ∈ is a minimum value.

[0034] Preferably, the calculating the sliding mode control coefficient according to the bicycle pedal pressure data and the saddle pressure data comprises: obtaining the bicycle pedal pressure data and the bicycle saddle pressure data, extracting abnormal pedal pressure data and abnormal saddle pressure data, normalizing the bicycle pedal pressure data and the bicycle saddle pressure data, and calculating the sliding mode control coefficient by the sliding mode control coefficient formula, and the sliding mode control coefficient formula is as follows,

[0035]

[0036] wherein SMC is a sliding mode control coefficient, w1 and w2 are weight coefficients of the seat pressure and the pedal pressure part respectively, w1 + w2 = 1, P seat,abn ' and P seat,norm ' are abnormal seat pressure normalized value and normal seat pressure normalized value respectively, P pedal,abn ' and P pedal,norm ' are abnormal pedal pressure normalized value and normal pedal pressure normalized value respectively, and ∈ is a minimum value.

[0037] Preferably, the bicycle trajectory tracking sliding mode control method is determined based on the bicycle obstacle avoidance success coefficient and the sliding mode control coefficient, comprising:

[0038] In the downhill section, if the bicycle avoids obstacles successfully, the value of w2 is reduced; if the bicycle fails to avoid obstacles, the value of w2 is increased;

[0039] In the process of reducing w2, if the obstacle failure section starting marker distance is reduced, stop reducing w2 and increase the value of w1; if the obstacle failure section starting marker distance is increased, stop increasing w2 and reduce the value of w1; w1 and w2 are not 0, and the sum is always less than or equal to 1 in the changing process;

[0040] If an unrecognized obstacle appears, the weight coefficient is dynamically adjusted again.

[0041] Preferably, if an unrecognized obstacle appears, the weight coefficient is dynamically adjusted again, comprising:

[0042] In the downhill section, if the pedal pressure is increased by the rider, the value of w2 is increased; if the seat pressure is increased passively without the rider applying additional pressure to the pedal, the value of w1 is increased;

[0043] Active increase means that the rider actively applies pressure to the bicycle pedal;

[0044] Passive increase means that the bicycle seat pressure is increased without the rider increasing pressure on the bicycle pedal.

[0045] Preferably, a bicycle trajectory tracking sliding mode control system comprises:

[0046] A data acquisition module collects obstacle avoidance data, pedal pressure data and seat pressure data of the bicycle in the downhill section; real-time data is collected using sensors installed at key parts of the bicycle;

[0047] A relevant parameter calculation module calculates the first dispensing speed, the second dispensing speed, the first pressure, and the second pressure.

[0048] A bicycle obstacle avoidance success coefficient calculation module calculates the bicycle obstacle avoidance success coefficient according to the normalized speed and pressure data.

[0049] A trajectory tracking route generation module generates or adjusts the trajectory tracking route of the bicycle according to the obstacle avoidance success coefficient; a threshold T for obstacle avoidance qualification is set, and whether the obstacle avoidance success coefficient meets the condition is checked to determine whether the obstacle avoidance is successful; a road segment that fails in obstacle avoidance is marked, and a marking distance D is determined through an obstacle avoidance road segment marking formula.

[0050] A sliding mode control coefficient calculation module calculates the sliding mode control coefficient SMC according to the pressure data of the pedals and the saddle.

[0051] A control strategy adjustment module dynamically adjusts the weight coefficients w1 and w2 in the control strategy according to the obstacle avoidance situation.

[0052] Beneficial effects: The present application collects the obstacle avoidance, pedal pressure, and saddle pressure data of the bicycle on a downhill road segment, accurately calculates the obstacle avoidance success coefficient, determines the obstacle avoidance situation, marks the failed road segment, and updates the trajectory, greatly improving the obstacle avoidance ability and trajectory tracking accuracy. On the other hand, the sliding mode control coefficient and the weight coefficient are dynamically adjusted according to various real-time data, realizing adaptive optimization of the control system, so that it can flexibly fit the running state of the bicycle. At the same time, from the perspective of riding experience, the riding safety on the downhill is ensured, and the comfort is improved due to the control adjustment that fits the riding state. In addition, the collection and complex calculation of multiple data greatly improve the data utilization efficiency, making the entire system run more efficiently and intelligently. BRIEF DESCRIPTION OF DRAWINGS

[0053] Figure 1 A flowchart of the bicycle trajectory tracking sliding mode control method of the present application;

[0054] Figure 2 A system diagram of the bicycle trajectory tracking sliding mode control of the present application. DETAILED DESCRIPTION

[0055] The technical solutions in the embodiments of the present application will be described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0056] Embodiment 1: A bicycle trajectory tracking sliding mode control method, as shown in Figure 1 includes the following steps:

[0057] S1: acquiring bicycle obstacle avoidance data, bicycle pedal pressure data and saddle pressure data on a downhill section;

[0058] S2: determining a bicycle obstacle avoidance success coefficient and generating a bicycle trajectory tracking route;

[0059] S3: calculating a sliding mode control coefficient according to the bicycle pedal pressure data and the saddle pressure data;

[0060] S4: determining a bicycle trajectory tracking sliding mode control method based on the bicycle obstacle avoidance success coefficient and the sliding mode control coefficient.

[0061] On a downhill section, bicycle obstacle avoidance data, bicycle pedal pressure data and saddle pressure data are acquired, including:

[0062] The obstacle avoidance data refers to speed data before bicycle obstacle avoidance and speed data after bicycle obstacle avoidance;

[0063] The bicycle pedal pressure data refers to pedal pressure data before bicycle obstacle avoidance;

[0064] The bicycle saddle pressure data refers to saddle pressure data after bicycle obstacle avoidance;

[0065] The intervention speed of the bicycle sliding mode before obstacle avoidance and the intervention speed after obstacle avoidance are collected;

[0066] Based on the obstacle avoidance data, the bicycle pedal pressure data, the bicycle saddle pressure data and the bicycle sliding mode intervention speed, the related parameters of the bicycle obstacle avoidance calculation formula are calculated, including a first allocation speed, a second allocation speed, a first pressure and a second pressure.

[0067] Further, the speed data before and after bicycle obstacle avoidance reflects the speed change of the bicycle due to obstacle avoidance operation, and can intuitively present the influence of obstacle avoidance on driving speed, such as whether the speed is reasonably reduced or abnormally fluctuated. The pedal pressure data before bicycle obstacle avoidance reflects the size of the force applied by the rider when anticipating obstacle avoidance, which can help understand the operation strength and intention of the rider in actively responding to obstacle avoidance. The saddle pressure data after obstacle avoidance can reflect the body posture and force condition of the rider after obstacle avoidance is completed, which reflects the influence of obstacle avoidance on the riding state. The intervention speed of the sliding mode before and after obstacle avoidance shows the speed state of the bicycle when the control means is intervened.

[0068] The related parameters of the bicycle obstacle avoidance calculation formula are calculated, including:

[0069] The speed before bicycle obstacle avoidance minus the speed before sliding mode intervention is taken as the first allocation speed;

[0070] The speed after bicycle obstacle avoidance minus the speed after sliding mode intervention is taken as the second allocation speed;

[0071] the pedal pressure minus the pedal pressure after the sliding mode intervention as the first pressure;

[0072] the saddle pressure minus the saddle pressure after the sliding mode intervention as the second pressure;

[0073] normalizing the first allocated speed, the second allocated speed, the first pressure, and the second pressure by a normalization formula.

[0074] Further, the first allocated speed reflects the natural speed adjustment of the bicycle when the obstacle avoidance is about to be performed but the control has not yet been completely intervened, and embodies the initial state change of autonomous obstacle avoidance. The second allocated speed exhibits the speed difference after the obstacle avoidance operation is completed compared to the speed after the control is intervened, and can be seen that the stability of the bicycle speed at the end of the obstacle avoidance. The first pressure and the second pressure are obtained based on the difference between the pedal pressure and the corresponding pressure after the sliding mode intervention, and the difference between the saddle pressure and the corresponding pressure after the sliding mode intervention, respectively, and embody the pressure change of the rider before and after the obstacle avoidance due to the operation and the state change. Finally, the normalization processing is performed, so as to unify the change amounts of different magnitudes and different ranges to a specific standard range.

[0075] normalizing the first allocated speed, the second allocated speed, the first pressure, and the second pressure by a normalization formula, including that the normalization formula is as follows,

[0076]

[0077] wherein, x min and x max are the minimum value and the maximum value of the variable, respectively.

[0078] determining a bicycle obstacle avoidance success coefficient and generating a bicycle trajectory tracking route, including: determining the bicycle obstacle avoidance success coefficient by a bicycle obstacle avoidance calculation formula, and generating the bicycle trajectory tracking route based on the bicycle obstacle avoidance success coefficient, the bicycle obstacle avoidance calculation formula being as follows,

[0079]

[0080] wherein, C success is the bicycle obstacle avoidance success coefficient, V first-norm and V second-norm are the normalized first allocated speed and the normalized second allocated speed, respectively, P pedal-first-norm and P seat-second-norm are the normalized first pressure and the normalized second pressure, respectively, and ∈ is a minimum value; the normalized first allocated speed V first-norm = V pre -V control , and the normalized second allocated speed V second-norm = V post-V control , the normalized first pressure P pedal-first-norm = P pedal,pre -P pedal,control , the normalized second pressure P seat-second-norm = P seat,post -P seat,control .

[0081] Further, the formula comprehensively considers the influence of the speed change before and after obstacle avoidance and the corresponding pressure change on the success of obstacle avoidance. If the first and second preset speeds both meet the preset threshold, and the corresponding first and second pressure changes also meet the preset range of the cycling and obstacle avoidance logic, the value of C success will be in a suitable range; otherwise, if the speed or pressure parameter of one part is abnormal, such as the speed change being too large but the pressure change being unreasonable, or the pressure change being normal but the speed recovery being poor, the value of the corresponding fraction will deviate, and thus the value of C success will deviate from the normal range, indicating that there is a problem in the obstacle avoidance process.

[0082] Generating a bicycle trajectory tracking route, comprising:

[0083] Based on the bicycle obstacle avoidance success coefficient, a threshold T for obstacle avoidance qualification is set. If C success is greater than or equal to T, the obstacle avoidance is successful; otherwise, the obstacle avoidance fails.

[0084] Obtaining the original trajectory tracking route of the bicycle, and marking the obstacle avoidance failure section;

[0085] The obstacle avoidance failure section is marked by an obstacle avoidance section marking formula as follows,

[0086]

[0087] wherein D is the starting marking distance of the obstacle avoidance failure section, L prev is the position of the successful obstacle avoidance section, L fail is the position of the next obstacle avoidance failure section adjacent to the successful obstacle avoidance section position, norm() is a normalization function, m is the number of failure obstacle avoidance section markings of the next obstacle avoidance failure section adjacent to the successful obstacle avoidance section position, is the average value of the number of failure obstacle avoidance section markings of all next obstacle avoidance failure sections adjacent to the successful obstacle avoidance section position in the entire section, and ∈ is a minimum value.

[0088] Further, it is assumed that in a section of the cycling route, the position L prevL is the position of the next obstacle avoidance failure section adjacent to the successful obstacle avoidance section at 100 meters (the unit here is set according to the actual situation) fail L is the position of the next obstacle avoidance failure section adjacent to the successful obstacle avoidance section at 120 meters prev L fail = 100-120 = -20 meters (the negative sign here only represents the direction, and in actual application, the absolute value is taken according to the regulations or other methods). Assuming that the value of the failure obstacle avoidance section marker number m of the failure section after being processed by the normalization function norm() is 0.3, the average value of the failure obstacle avoidance section marker number of all the next obstacle avoidance failure sections adjacent to the successful obstacle avoidance section in the entire section is 0.5, and the minimum value ∈ takes a very small value such as 0.001. Substituting these values into the formula gives D = (-20) / (1-0.3+0.001) x 0.5, and the specific obstacle avoidance failure section starting marker distance D value is obtained by calculation, which accurately marks the distance position from the successful obstacle avoidance section to the beginning of this adjacent obstacle avoidance failure section.

[0089] The slip mode control coefficient is calculated according to the bicycle pedal pressure data and the saddle pressure data, including: obtaining the bicycle pedal pressure data and the bicycle saddle pressure data, extracting abnormal pedal pressure data and abnormal saddle pressure data, normalizing the bicycle pedal pressure data and the bicycle saddle pressure data, calculating the slip mode control coefficient through the slip mode control coefficient formula, and the slip mode control coefficient formula is as follows,

[0090]

[0091] wherein SMC is the slip mode control coefficient, w1 and w2 are weight coefficients of the saddle pressure and pedal pressure parts respectively, w1+w2=1, P seat,abn ' and P seat,norm ' are the normalized values of abnormal saddle pressure and normal saddle pressure respectively, P pedal,abn ' and P pedal,norm ' are the normalized values of abnormal pedal pressure and normal pedal pressure respectively, and ∈ is the minimum value.

[0092] Further, w1 and w2 in the formula are weight coefficients, and w1+w2=1. This means that the proportions of the saddle pressure and pedal pressure parts in the calculation of the slip mode control coefficient SMC are mutually restricted, and their sum is always 1, representing the comprehensive influence of the two factors on the overall slip mode control. For the saddle pressure part, the exponential function is used when the saddle pressure is abnormal (such as being impacted by external forces or the rider's posture changing) seat,abn' With P seat,norm ' The ratio will change. If this ratio increases, meaning the deviation of abnormal pressure from normal pressure becomes greater, it reflects that the impact of abnormal seat pressure on the sliding mode control coefficient is amplified, thus highlighting the importance of abnormal seat pressure in control. The pedal pressure section uses a logarithmic function. When abnormal pedal pressure occurs (such as the rider suddenly applying or releasing the pedal), P pedal,abn ' With P pedal,norm ' The ratio changes. When this ratio changes, the value of the logarithmic function changes accordingly, thus increasing the weight w2 to affect the sliding mode control coefficient SMC. This relatively gradual change more stably reflects the impact of abnormal pedal pressure on the control coefficient.

[0093] Based on the bicycle obstacle avoidance success coefficient and sliding mode control coefficient, a bicycle trajectory tracking sliding mode control method is determined, including:

[0094] On a downhill section, if the bicycle successfully avoids the obstacle, the value of w2 is decreased; if the bicycle fails to avoid the obstacle, the value of w2 is increased.

[0095] During the decrease of w2, if the distance to the starting marker of the obstacle avoidance failure section decreases, then stop decreasing w2 and increase the value of w1; if the distance to the starting marker of the obstacle avoidance failure section increases, then stop increasing w2 and decrease the value of w1; neither w1 nor w2 is 0, and their sum is always less than or equal to 1 during the change.

[0096] If an unidentified obstacle is encountered, the weighting coefficients will be dynamically adjusted again.

[0097] To further explain, when obstacle avoidance is successful, it indicates that the current control strategy is effective, and saddle pressure contributes more to the stable trajectory. Therefore, the weight of pedal pressure should be reduced, for example, w2 is adjusted from 0.4 to 0.3, and w1 is changed from 0.6 to 0.7. If obstacle avoidance fails, the change in pedal pressure contains information about the rider's active operation. To improve the success rate of obstacle avoidance, w2 needs to be increased, for example, w2 is adjusted from 0.3 to 0.4, and w1 is changed to 0.6. During the adjustment process, the distance D from the starting marker of the obstacle avoidance failure segment also affects the weight. When D decreases, it indicates that w2 was previously reduced too much, and the reduction of w2 should be stopped and w1 increased; if D increases, it indicates that the strategy of increasing w2 is not good, and the increase of w2 should be stopped and w1 decreased. When encountering an unidentified obstacle, if the pedal pressure increases actively, increase w2, allowing the control strategy to adjust the trajectory based on the pedal pressure; if the saddle pressure increases passively, it indicates that the bicycle is affected by external factors. In this case, increase w1 and pay attention to the state changes reflected by the saddle pressure. Always ensure that w1 and w2 are not 0 and their sum is less than or equal to 1, thus guaranteeing the rationality and controllability of the control strategy.

[0098] If an unrecognized obstacle appears, the weight parameter is dynamically adjusted again, including:

[0099] In the downhill section, if the pedal pressure is actively increased by the rider, the value of w2 is increased; if the saddle pressure is passively increased without the rider applying additional pressure to the pedal, the value of w1 is increased;

[0100] Active increase means that the rider actively applies pressure on the bicycle pedal;

[0101] Passive increase means that the bicycle saddle pressure increases without the rider increasing pressure on the bicycle pedal.

[0102] Further explanation is that in the downhill situation of the bicycle, if the pedal pressure is actively increased by the rider, it means that he perceives the road condition change, and the value of w2 is increased, so that the control strategy is adjusted according to his intention. If the pedal is actively pedaled when encountering a small bump, w2 is increased from 0.3 to 0.4, which is beneficial to accurate trajectory tracking. The saddle pressure is passively increased without the rider actively increasing the pedal pressure, which is mostly due to external factors such as crosswind and pressing stones. At this time, the value of w1 is increased, so that the control focuses on the state change reflected by the saddle pressure to stabilize the trajectory. When encountering crosswind, w1 is increased from 0.6 to 0.7, which improves the adaptability and robustness of the control to complex environments.

[0103] Embodiment 2: Based on embodiment 1, as shown in Figure 2 A bicycle trajectory tracking sliding mode control system includes:

[0104] A data acquisition module collects obstacle avoidance data, pedal pressure data and saddle pressure data of the bicycle in the downhill section; real-time data is collected using sensors installed at key parts of the bicycle;

[0105] A related parameter calculation module calculates the first allocation speed, the second allocation speed, the first pressure and the second pressure;

[0106] A bicycle obstacle avoidance success coefficient calculation module calculates the bicycle obstacle avoidance success coefficient according to the normalized speed and pressure data;

[0107] A trajectory tracking route generation module generates or adjusts the trajectory tracking route of the bicycle according to the obstacle avoidance success coefficient; sets an obstacle avoidance qualified threshold T to check whether the obstacle avoidance success coefficient meets the condition to determine whether the obstacle avoidance is successful; marks the road section where the obstacle avoidance fails, and determines the marking distance D through the obstacle avoidance road section marking formula;

[0108] A sliding mode control coefficient calculation module calculates the sliding mode control coefficient SMC according to the pedal and saddle pressure data;

[0109] The control strategy adjustment module dynamically adjusts the weight coefficients w1 and w2 in the control strategy according to the obstacle avoidance situation.

[0110] The above has carried out the detailed introduction to the application, the principle and implementation mode of the application are set forth by applying specific examples in this paper, the above example is only used for helping understanding the method and its core idea of the application; at the same time, for the general technical personnel in the art, according to the idea of the application, the specific implementation mode and application range will have the change, and the above-mentioned, the content of the specification should not be understood as the limitation of the application.

Claims

1. A bicycle trajectory tracking sliding mode control method, characterized by, The method comprises the following steps: S1: obtaining bicycle obstacle avoidance data, bicycle pedal pressure data and bicycle seat pressure data on a downhill section; S2: determining a bicycle obstacle avoidance success coefficient and generating a bicycle trajectory tracking route; S3: calculating a sliding mode control coefficient according to the bicycle pedal pressure data and the bicycle seat pressure data, comprising: obtaining bicycle pedal pressure data and bicycle seat pressure data, extracting abnormal pedal pressure data and abnormal seat pressure data, normalizing the bicycle pedal pressure data and the bicycle seat pressure data, and calculating a sliding mode control coefficient through a sliding mode control coefficient formula, the sliding mode control coefficient formula being as follows, wherein SMC is a sliding mode control coefficient, w1 and w2 are weight coefficients of the seat pressure and the pedal pressure part respectively, w1 + w2 = 1, P seat,abn ' and P seat,norm ' are an abnormal seat pressure normalized value and a normal seat pressure normalized value respectively, P pedal,abn ' and P pedal,norm ' are an abnormal pedal pressure normalized value and a normal pedal pressure normalized value respectively, and ∈ is a minimum value. S4: determining a bicycle trajectory tracking sliding mode control method based on the bicycle obstacle avoidance success coefficient and the sliding mode control coefficient, comprising: on the downhill section, if the bicycle obstacle avoidance is successful, the value of w2 is reduced; if the bicycle obstacle avoidance fails, the value of w2 is increased; in the process of reducing w2, if the starting marker distance of the obstacle avoidance failure section is reduced, the reduction of w2 is stopped and the value of w1 is increased; if the starting marker distance of the obstacle avoidance failure section is increased, the increase of w2 is stopped and the value of w1 is reduced; w1 and w2 are not 0, and the sum is always less than or equal to 1 in the changing process; if an unrecognized obstacle appears, the weight coefficient is dynamically adjusted again.

2. A bicycle trajectory tracking sliding mode control method as claimed in claim 1, characterized in that, The bicycle obstacle avoidance data, the bicycle pedal pressure data and the bicycle seat pressure data on the downhill section comprise: the obstacle avoidance data refers to speed data before bicycle obstacle avoidance and speed data after bicycle obstacle avoidance; the bicycle pedal pressure data refers to pedal pressure data before bicycle obstacle avoidance; the bicycle seat pressure data refers to seat pressure data after bicycle obstacle avoidance; the intervention speed of the bicycle sliding mode before obstacle avoidance and the intervention speed after obstacle avoidance are collected; based on the obstacle avoidance data, the bicycle pedal pressure data, the bicycle seat pressure data and the bicycle sliding mode intervention speed, the related parameters of the bicycle obstacle avoidance calculation formula are calculated, the related parameters comprising a first allocation speed, a second allocation speed, a first pressure and a second pressure.

3. A bicycle trajectory tracking sliding mode control method as claimed in claim 2, characterized in that, The calculation of the related parameters of the bicycle obstacle avoidance calculation formula comprises: the speed before bicycle obstacle avoidance minus the speed before sliding mode intervention is taken as the first allocation speed; the speed after bicycle obstacle avoidance minus the speed after sliding mode intervention is taken as the second allocation speed; the pedal pressure minus the pedal pressure after sliding mode intervention is taken as the first pressure; the seat pressure minus the seat pressure after sliding mode intervention is taken as the second pressure; the first allocation speed, the second allocation speed, the first pressure and the second pressure are normalized through a normalization formula.

4. A bicycle trajectory tracking sliding mode control method as claimed in claim 3, characterized in that, The normalization of the first allocation speed, the second allocation speed, the first pressure and the second pressure through the normalization formula comprises: where x min and x max are the minimum and maximum values of the variable, respectively.

5. The bicycle trajectory tracking sliding mode control method of claim 1, wherein, the normalization formula is as follows, The determination of the bicycle obstacle avoidance success coefficient and the generation of the bicycle trajectory tracking route comprise: Wherein, C success is the success coefficient of obstacle avoidance of the bicycle, V first-norm and V second-norm are the first and second normalized delivery speeds respectively, P pedal-first-norm and P seat-second-norm are the first and second normalized pressures respectively; the first normalized delivery speed V first-norm = V pre -V control , the second normalized delivery speed V second-norm = V post -V control , the first normalized pressure P pedal-first-norm = P pedal,pre -P pedal,control , and the second normalized pressure P seat-second-norm = P seat,post -P seat,control .

6. A bicycle trajectory tracking sliding mode control method as claimed in claim 5, characterized in that, the bicycle obstacle avoidance success coefficient is determined through a bicycle obstacle avoidance calculation formula, and the bicycle trajectory tracking route is generated based on the bicycle obstacle avoidance success coefficient, the bicycle obstacle avoidance calculation formula being as follows, Based on the success coefficient of the bicycle obstacle avoidance, a qualified threshold T of obstacle avoidance is set. If C success is greater than or equal to T, the obstacle avoidance is successful; otherwise, the obstacle avoidance fails. The generation of the bicycle trajectory tracking route comprises: an original bicycle trajectory tracking route is obtained, and an obstacle avoidance failure section is marked. The obstacle avoidance failure section is marked by an obstacle avoidance section marking formula, and the obstacle avoidance section marking formula is as follows, wherein D is the start marker distance of the obstacle avoidance failure section, L prev is the position of the successful obstacle avoidance section, L fail is the position of the next obstacle avoidance failure section adjacent to the position of the successful obstacle avoidance section, norm() is a normalization function, and m is the number of failure obstacle avoidance section markers of the next obstacle avoidance failure section adjacent to the position of the successful obstacle avoidance section, is the average of the number of failure obstacle avoidance section markers of all next obstacle avoidance failure sections adjacent to the position of the successful obstacle avoidance section in the entire section.

7. A bicycle trajectory tracking sliding mode control method as claimed in claim 6, characterized in that, If an unrecognized obstacle appears, the weight coefficient is dynamically adjusted again, including: In the downhill section, if the pedal pressure is actively increased by the rider, the value of w2 is increased; if the saddle pressure is passively increased without the rider applying additional pressure to the pedal, the value of w1 is increased; Active increase means that the rider actively applies pressure to the bicycle pedal; Passive increase means that the bicycle saddle pressure increases without the rider increasing pressure on the bicycle pedal.

8. A bicycle trajectory tracking sliding mode control system for implementing the bicycle trajectory tracking sliding mode control method of any one of claims 1-7, characterized by, It includes: A data acquisition module collects obstacle avoidance data, pedal pressure data, and saddle pressure data of the bicycle in the downhill section; real-time data is collected using sensors installed at key parts of the bicycle; A related parameter calculation module calculates the first allocation speed, the second allocation speed, the first pressure, and the second pressure; A bicycle obstacle avoidance success coefficient calculation module calculates the bicycle obstacle avoidance success coefficient according to normalized speed and pressure data; A trajectory tracking route generation module generates or adjusts the trajectory tracking route of the bicycle according to the obstacle avoidance success coefficient; An obstacle avoidance qualified threshold T is set, and it is checked whether the obstacle avoidance success coefficient meets the condition to determine whether the obstacle avoidance is successful; The section that fails to avoid obstacles is marked, and the marking distance D is determined by the obstacle avoidance section marking formula; A sliding mode control coefficient calculation module calculates the sliding mode control coefficient SMC according to the pressure data of the pedal and the saddle; A control strategy adjustment module dynamically adjusts the weight coefficients w1 and w2 in the control strategy according to the obstacle avoidance situation.

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