CN117261846A - Brake control method and system based on aircraft variable load - Google Patents
Brake control method and system based on aircraft variable load Download PDFInfo
- Publication number
- CN117261846A CN117261846A CN202311354504.9A CN202311354504A CN117261846A CN 117261846 A CN117261846 A CN 117261846A CN 202311354504 A CN202311354504 A CN 202311354504A CN 117261846 A CN117261846 A CN 117261846A
- Authority
- CN
- China
- Prior art keywords
- aircraft
- deceleration rate
- variable load
- speed section
- target
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 41
- 238000004364 calculation method Methods 0.000 claims description 20
- 230000008569 process Effects 0.000 claims description 12
- 230000008859 change Effects 0.000 claims description 7
- 238000004590 computer program Methods 0.000 claims description 3
- 238000013461 design Methods 0.000 description 7
- 238000012360 testing method Methods 0.000 description 4
- 230000009467 reduction Effects 0.000 description 3
- 238000012935 Averaging Methods 0.000 description 2
- 230000001276 controlling effect Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 230000003044 adaptive effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000011217 control strategy Methods 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 230000001960 triggered effect Effects 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
- B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
- B60T8/17—Using electrical or electronic regulation means to control braking
- B60T8/1701—Braking or traction control means specially adapted for particular types of vehicles
- B60T8/1703—Braking or traction control means specially adapted for particular types of vehicles for aircrafts
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
- B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
- B60T8/17—Using electrical or electronic regulation means to control braking
- B60T8/172—Determining control parameters used in the regulation, e.g. by calculations involving measured or detected parameters
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
- B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
- B60T8/32—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration
- B60T8/58—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration responsive to speed and another condition or to plural speed conditions
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C25/00—Alighting gear
- B64C25/32—Alighting gear characterised by elements which contact the ground or similar surface
- B64C25/42—Arrangement or adaptation of brakes
- B64C25/426—Braking devices providing an automatic sequence of braking
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Transportation (AREA)
- Aviation & Aerospace Engineering (AREA)
- Regulating Braking Force (AREA)
Abstract
The invention relates to a brake control method and a brake control system based on aircraft variable load, belonging to the technical field of aircraft brake control; the method comprises the steps of calculating the current deceleration rate of the airplane after being grounded; under each speed section, the aircraft presets a target range of the deceleration rate according to the variable load state; the speed section of the airplane is divided into a high speed section, a medium speed section and a low speed section, the deceleration rate of the airplane is lower than the target deceleration rate in the high speed section, the deceleration rate of the airplane is within the deceleration rate range of the target deceleration rate and the anti-skid entrance threshold in the medium speed section, and the deceleration rate of the airplane is lower than the target deceleration rate in the low speed section; and according to the comparison of the current deceleration rate and the deceleration rate target range, the control of the braking pressure of the aircraft is completed by combining the braking pressure control law. The invention solves the problems generated by the quasi-regulation type control mode based on rated brake pressure in the prior art.
Description
Technical Field
The invention belongs to the technical field of aircraft brake control, and particularly relates to a brake control method and system based on aircraft variable load.
Background
The aircraft anti-skid braking system is a complex non-linear system with uncertainty, and a plurality of non-linear factors exist in the system and directly influence the performance of the anti-skid braking. The landing and sliding process time of the aircraft is short, so that the anti-skid braking system is required to work stably, rapidly and accurately, and the safety of the aircraft is ensured.
The performance of an anti-skid braking system is affected by a number of factors, conventional controls taking into account runway conditions (dry, wet or snow, etc.), inflation pressure of the tires, etc. In addition to the above factors, variations in aircraft tire load at different aircraft taxiing speeds are also important to the performance impact of the anti-skid brake system.
Most aircraft employ conventional quasi-regulated control based on rated brake pressure, which has the following disadvantages:
1) The lack of adaptability to variable load of the aircraft results in underutilization of the braking capacity provided by the braking system on the brake disc;
2) The pressure control mode is too single, so that the overshoot problem is easy to occur during the system control;
3) At low speed, the design of brake pressure is unreasonable, and locking easily occurs, so that the problem of tire supporting and tire burst is caused.
The rated brake pressure control mode has more obvious defect exposure in the humid and rainwater environment in the south, and the condition that the aircraft rushes out of a runway can be caused in the actual use process.
Essentially, these factors affect the bonding force of the tires to the runway surface and the rolling resistance, and the main purpose of the anti-skid braking system is to make full use of the bonding force provided by the runway to brake the aircraft in the shortest possible distance. Therefore, the aircraft braking control should comprehensively consider the aircraft variable load; the load of the wheels in the braking process of the aircraft is continuously changed, the overall trend is gradually changed from small to large, and finally the wheels tend to be stable, so that the design of the braking pressure should consider the change trend of the load; when the aircraft speed is lower, the speed change rate of the aircraft wheel is lower in a rated brake pressure state, so that the anti-skid working sensitivity is lower, the active depressurization is not triggered in advance, and the deep slipping of the aircraft wheel is easy to occur.
Based on analysis, based on the variable load characteristic in the aircraft braking process, a reasonable pressure control mode is designed to be particularly important for the safety and reliability of a braking system.
Disclosure of Invention
The technical problems to be solved are as follows:
in order to avoid the defects of the prior art, the invention provides a braking control method and a braking control system based on variable load of an airplane. The invention solves the problems generated by the quasi-regulation type control mode based on rated brake pressure in the prior art.
The technical scheme of the invention is as follows: a brake control method based on aircraft variable load comprises the following specific steps:
calculating the current deceleration rate of the aircraft after being grounded;
under each speed section, the aircraft presets a target range of the deceleration rate according to the variable load state; the speed section of the airplane is divided into a high speed section, a medium speed section and a low speed section, the deceleration rate of the airplane is lower than the target deceleration rate in the high speed section, the deceleration rate of the airplane is within the deceleration rate range of the target deceleration rate and the anti-skid entrance threshold in the medium speed section, and the deceleration rate of the airplane is lower than the target deceleration rate in the low speed section;
and according to the comparison of the current deceleration rate and the deceleration rate target range, the control of the braking pressure of the aircraft is completed by combining the braking pressure control law.
The invention further adopts the technical scheme that: the method for calculating the current deceleration rate of the aircraft after grounding is as follows,
equally dividing 0.3s into 10 interval sections, wherein one interval is 0.03s, namely 3 software running periods, and calculating the deceleration rate of each interval as follows:
a 01 ＝(V 2 -V 1 )/T； (1)
a 02 ＝(V 3 -V 2 )/T； (2)
a 0 ＝(a 01 +a 02 )/2； (3)
wherein a is 01 Is the average deceleration rate between the first period and the second period, a 02 Is the average deceleration rate between the second cycle and the third cycle; v (V) 3 For the third period of aircraft speed, V 2 For the second period of aircraft speed, V 1 The aircraft speed is the first period, and T is the software running period;
calculation of a 0 ～a 9 Sum is a m The steady state deceleration is averaged, i.e. as the current deceleration:
a v ＝(a m -a max -a min )/8； (4)
wherein a is 0 ～a 9 For an average deceleration rate of 10 times calculated within 0.3s, a max For maximum average deceleration rate, a min Is the minimum average deceleration rate.
The invention further adopts the technical scheme that: the high speed section, the medium speed section and the low speed section of the airplane speed section are respectively 220km/h, 70 km/h-220 km/h and 25 km/h-70 km/h.
The invention further adopts the technical scheme that: setting the whole process deceleration rate target of a certain braking working condition as a, wherein the deceleration rate target of each aircraft speed section is as follows: a+Δa 0 ，Δa 0 Is the change value of the target deceleration rate under the variable load of the airplane.
The invention further adopts the technical scheme that: when the aircraft speed is more than 220km/h or 25 km/h-70 km/h, delta a 0 < 0; within other speed range Δa 0 ≥0。
The invention further adopts the technical scheme that: when the aircraft speed is 70 km/h-220 km/h, the target deceleration rate range is controlled to be a+delta a 0 And a f -between 2, a f Is an anti-slip entry threshold.
The invention further adopts the technical scheme that: the comparison result of the current deceleration rate and the deceleration rate target range and the brake pressure control law are specifically that,
if a is v ＜a+Δa 0 Braking pressure P S Increasing to a target range at a rate of 1 MPa/s;
if a is v ＞a f -Δa 0 Braking pressure P S Reducing to a target range at a rate of 2 MPa/s;
if a is f -2≥a v ≥a+Δa 0 Maintaining the brake pressure;
and after the anti-slip failure, the pressure is restored to the rated braking pressure.
A brake control system based on aircraft variable load comprises a brake unit for applying and adjusting brake pressure to a wheel; the sensor unit is arranged on the machine wheel and used for detecting the rotation speed and the load of the machine wheel; the control unit acquires signals of the sensor unit and the calculation unit and sends a control instruction to the brake unit; and the calculation unit is used for completing calculation in the braking control method based on the aircraft variable load.
The invention further adopts the technical scheme that: the control unit includes at least one processor, and a memory communicatively coupled to the at least one processor; wherein the memory stores a computer program executable by the at least one processor to enable the at least one processor to perform the aircraft variable load based brake control method.
An aircraft comprising the aircraft variable load based brake control system.
Advantageous effects
The invention has the beneficial effects that: according to the braking control method and system based on the variable load of the aircraft, the control of the braking pressure of the aircraft is realized by comparing the current deceleration rate with the target range of the deceleration rate and combining the braking pressure control law.
According to the invention, the variable load is used for controlling the deceleration rate target, and the optimal control of the pressure is realized based on the variable load characteristic by detecting the speed and weight signals of the airplane; and the variable load condition in the braking process of the aircraft is considered, so that the braking performance is effectively improved.
The invention designs the steady-state maximum deceleration rate target when the aircraft speed is 70 km/h-220 km/h as a+delta a and a f Between-2, it is possible to avoid too high a rate of deceleration, close to the slip point.
Drawings
FIG. 1 is a flow chart of a method of braking control based on aircraft variable load according to the present invention.
Detailed Description
The embodiments described below by referring to the drawings are illustrative and intended to explain the present invention and should not be construed as limiting the invention.
Based on the prior art, most airplanes adopt a conventional quasi-regulation type control mode based on rated brake pressure, and the problem that the system is easy to overshoot when in control because the braking system has insufficient braking capability provided by a brake disc due to the fact that the adaptive capacity of the airplane for changing loads is not provided; at low speed, the design of brake pressure is unreasonable, and locking easily appears, leads to holding in the palm the tire and bursts the scheduling problem. The invention provides a braking control method and a braking control system based on variable load of an airplane, wherein the method comprises the steps of firstly calculating the current deceleration rate of the airplane after grounding; then, under each speed section of the aircraft, presetting a target range of the deceleration rate according to the variable load state; and finally, according to the comparison of the current deceleration rate and the deceleration rate target range, the control of the braking pressure of the aircraft is completed by combining a braking pressure control rule. Based on the variable load characteristic in the aircraft braking process, the pressure control mode meets the safety and reliability of an aircraft braking system.
When the aircraft is grounded, the lift force P of the aircraft in the vertical direction of the ground is influenced by the aerodynamic layout in the whole braking process 0 Gradually decreasing as aircraft speed decreases, P 0 The lower the wheel is loaded, the greater the ground coupling torque is provided, the greater the aircraft deceleration capacity is, and therefore the braking pressure P S The vertical lifting force P should be considered in design 0 And lift P 0 Directly influencing the braking deceleration rate target of the airplane; aircraft speed V Ground (floor) When the brake pressure is higher, the brake efficiency can be effectively improved and the brake is shortenedBraking distance based on P 0 And V Ground (floor) The brake pressure control mode is designed, so that the load change is compatible, and the brake efficiency is improved.
Based on the principle, the design thought of the aircraft in the high, medium and low speed sections is as follows:
vertical lift force P when aircraft is braked at high speed 0 The aircraft has the advantages that the aircraft is relatively large, the load of the aircraft wheels is small, the binding force moment between the ground and the tires is small, and therefore the deceleration rate capability of the aircraft is low; the design goal of brake pressure should be reduced to avoid slipping.
Vertical lift force P when airplane is braked at medium speed 0 The wheel load is larger at the moment of the binding force between the ground and the tire is larger, the braking deceleration rate capability is higher at the moment, and larger braking pressure is applied.
Vertical lift P when the aircraft is braked at low speed 0 The wheel load is relatively low, but the wheel speed is low, the wheel speed variation range is small, the anti-skid working predictability is poor, deep skid is easy to cause, so that the brake pressure is actively reduced in advance according to the speed condition of the aircraft, the tire burst of the supporting tire is avoided, and the brake pressure is properly increased after the anti-skid failure, so that the aircraft is rapidly braked.
The specific steps of the braking control method based on the aircraft variable load in the embodiment are as follows:
step one: the ground connection condition of the airplane is judged through calculation of the deceleration rate, and after the airplane is grounded, the average deceleration rate a of 10 times is calculated within 0.3s according to the airplane speed 0 ～a 9 ，a 0 ～a 9 The calculation modes are the same, and a is filtered out 0 ～a 9 The maximum value and the minimum value of the speed reduction rate are taken as the average speed reduction rate a within 0.3s v . If the anti-skid operation occurs, the deceleration rate calculation is exited, after the brake pressure is restored to a stable state (the brake pressure value after the stabilization is smaller than the pressure value of the slipping point), the deceleration rate calculation is started again, and whether the brake pressure value meets the target deceleration rate requirement can be judged according to the steady state value of the deceleration rate.
Aiming at the thought, the specific calculation method of the steady-state deceleration rate comprises the following steps:the average of 0.3s is divided into 10 intervals (one interval is 0.03s, and generally 3 software running periods), and the deceleration rate of each interval is calculated as follows (V 3 For the third period of aircraft speed, V 2 For the second period of aircraft speed, V 1 For the first period aircraft speed, T is the software run period): a, a 01 Is the average deceleration rate between the first period and the second period, a 02 Is the average deceleration rate between the second cycle and the third cycle;
a 01 ＝(V 2 -V 1 )/T； (1)
a 02 ＝(V 3 -V 2 )/T； (2)
a 0 ＝(a 01 +a 02 )/2； (3)
calculation of a 0 ～a 9 Sum is a m Wherein the maximum value is a max Minimum value of a min Averaging steady state deceleration rate:
a v ＝(a m -a max -a min )/8； (4)
the step calculates the current airplane deceleration rate state according to the airplane speed, and realizes the calculation of the current deceleration rate.
Step two: variable load target deceleration rate range determination
Determining a target deceleration rate range, wherein under a certain braking working condition, the general whole process deceleration rate target is a, a is related to an aircraft weight signal, and the deceleration rate target at each aircraft speed section is as follows: a+Δa 0 ，Δa 0 For the change value of target deceleration rate under variable load of the aircraft, deltaa 0 The flight parameter data and the test result can be detected, and the delta a is detected when the aircraft speed is more than 220km/h or 25km/h to 70km/h 0 < 0; within other speed range Δa 0 Not less than 0; the target change in deceleration rate between the various speed points can be generally designed to be linear, and specifically adjusted according to a variable load test.
In order to ensure that the braking performance is further stable when the aircraft speed is 70 km/h-220 km/h, a steady-state maximum deceleration rate target is designed. The specific idea is as follows: the anti-skid entrance threshold is a f To avoid excessive deceleration rateHigh, near the slip point, the highest deceleration rate is generally controlled at a+Δa and a f -2.
Judging the maximum deceleration rate capability a of each aircraft under the speed according to the variable load condition of the aircraft n Taking the front three-point aircraft as an example, in general, the landing condition of the aircraft is judged according to weight signals, when the aircraft speed is above 220km/h, the vertical lift force of the aircraft is larger, and at the moment, the braking deceleration rate target a is reached n Should be properly lowered and gradually raised according to the aircraft speed; when the speed is 70 km/h-220 km/h, the lifting force of the airplane is smaller, the braking deceleration rate capability of the airplane is strongest, and the speed is an important speed interval for improving the braking efficiency; when the speed of the airplane is 25 km/h-70 km/h, the airplane speed is lower at the moment, and when the braking pressure is overlarge, the locking of the airplane wheel is easy to cause, so that the braking pressure is actively reduced in advance, and the braking safety is ensured; when the speed of the airplane is below 25km/h, the anti-skid device is in failure at the moment, the braking pressure is gradually increased to the rated value, and the airplane is rapidly braked.
The step is to preset a deceleration rate control range according to the variable load state of the aircraft in each speed section.
Step three: variable load pressure control mode
The currently calculated 0.3s average deceleration rate a v Target deceleration rate ranges (a+Δa) and (a) for and control f -2) compared, the control concept is as follows:
if a is v < a+Δa, the brake pressure P S Increasing to a target range at a rate of 1 MPa/s;
if a is v ＞a f -Δa 1 Braking pressure P S Reducing to a target range at a rate of 2 MPa/s;
if a is f -2≥a v ≥a+Δa 0 Maintaining the brake pressure;
and after the anti-slip failure, the pressure is restored to the rated braking pressure.
The control of the aircraft brake pressure is realized according to the current deceleration rate and the deceleration rate target range.
The embodiment provides a brake control system based on aircraft variable load, which comprises a brake unit, a brake control unit and a control unit, wherein the brake unit is used for applying and adjusting brake pressure to a wheel; the sensor unit is arranged on the machine wheel and used for detecting the rotation speed and the load of the machine wheel; the control unit acquires signals of the sensor unit and the calculation unit and sends a control instruction to the brake unit; and the calculation unit is used for completing calculation in the braking control method based on the aircraft variable load.
Specifically, the control unit comprises at least one processor and a memory communicatively connected with the at least one processor; wherein the memory stores a computer program executable by the at least one processor to enable the at least one processor to perform the aircraft variable load based brake control method.
The embodiment is applied to an aircraft, and the aircraft comprises the brake control system based on the variable load of the aircraft.
Examples:
the embodiment is a variable load-based pressure control method for a certain type of aircraft brake system, and is suitable for a front three-point digital fly-by-wire hydraulic brake system with aircraft speed signals and weight signals.
Step one: calculating the current deceleration rate of an aircraft
After the aircraft is grounded, the running period of software is 10ms, the deceleration rate is calculated by the aircraft speed signals of every 3 periods, and if the antiskid work occurs, the deceleration rate calculation is not performed; calculating the average deceleration rate a 10 times within 0.3s 0 ～a 9 Filtering the maximum value and the minimum value, taking the average value of the deceleration rate as the average deceleration rate a in 0.3s v 。
a 01 ＝(V 2 -V 1 )/T； (1)
a 02 ＝(V 3 -V 2 )/T； (2)
a 0 ＝(a 01 +a 02 )/2； (3)
Calculation of a 0 ～a 9 Sum is a m Wherein the maximum value is a max Minimum value of a min Averaging the deceleration rate:
a v ＝(a m -a max -a min )/8； (4)
the reduction rate is generally calculated to be (2-5) m/s 2 Between them.
Step two: variable load target deceleration rate range determination
Normal landing condition, the target requirement of general deceleration rate is 3.2m/s 2 Delta a at aircraft speed of 300km/h 0 Taking-1 m/s 2 The brake pressure corresponds to about 6MPa; Δa 0 As the aircraft speed becomes smaller and gradually increases, delta a is increased when the aircraft speed is 220km/h 0 Taking 0, wherein the braking pressure corresponds to about 10MPa; when the aircraft speed is 100 km/h-200 km/h, delta a 0 Taking 1.5m/s 2 ～2.0m/s 2 The braking pressure is about 12MPa to 14MPa; Δa at an aircraft speed of 70km/h 0 Taking 0, wherein the braking pressure corresponds to about 10MPa; Δa at an aircraft speed of 50km/h 0 Taking-1 m/s 2 The brake pressure corresponds to about 6MPa; and after the anti-slip failure, the brake pressure is restored to 10MPa.
Step three: variable load pressure control mode
And calculating the deceleration rate and comparing the target deceleration rate, controlling the braking pressure, and finally realizing the variable load control of the whole braking process.
The main test data are compared with the data in the table 2, and according to the data in the table and theoretical analysis, the brake capability of the main machine wheel cannot be fully exerted in the middle-high speed section in the rated pressure control mode, the main machine wheel is easy to enter a slipping state in the low-speed section, the brake capability of the main machine wheel is fully exerted in the high-middle speed section according to the deceleration rate control strategy under variable load, and finally, the whole brake process ensures that the deceleration rate is higher than rated pressure control, and meanwhile, the brake deceleration rate, the brake distance, the brake performance and the like are all superior to the rated pressure control law.
TABLE 2 Main test data
In the embodiment, through identifying the weight signal of the aircraft, the variable load characteristic of the aircraft is judged according to the speed signal of the aircraft, the optimal control of the brake pressure is realized according to the target range of the deceleration rate under the variable load, and experiments and theoretical analysis show that the brake performance of the brake system is improved based on the brake control mode of the variable load.
Although embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and not to be construed as limiting the invention, and that variations, modifications, alternatives, and variations may be made in the above embodiments by those skilled in the art without departing from the spirit and principles of the invention.
Claims (10)
1. A brake control method based on aircraft variable load is characterized by comprising the following specific steps:
calculating the current deceleration rate of the aircraft after being grounded;
under each speed section, the aircraft presets a target range of the deceleration rate according to the variable load state; the speed section of the airplane is divided into a high speed section, a medium speed section and a low speed section, the deceleration rate of the airplane is lower than the target deceleration rate in the high speed section, the deceleration rate of the airplane is within the deceleration rate range of the target deceleration rate and the anti-skid entrance threshold in the medium speed section, and the deceleration rate of the airplane is lower than the target deceleration rate in the low speed section;
and according to the comparison of the current deceleration rate and the deceleration rate target range, the control of the braking pressure of the aircraft is completed by combining the braking pressure control law.
2. The method for controlling braking based on variable load of an aircraft according to claim 1, wherein: the method for calculating the current deceleration rate of the aircraft after grounding is as follows,
equally dividing 0.3s into 10 interval sections, wherein one interval is 0.03s, namely 3 software running periods, and calculating the deceleration rate of each interval as follows:
a 01 ＝(V 2 -V 1 )/T； (1)
a 02 ＝(V 3 -V 2 )/T； (2)
a 0 ＝(a 01 +a 02 )/2； (3)
wherein a is 01 Is the average deceleration rate between the first period and the second period, a 02 Is the average deceleration rate between the second cycle and the third cycle; v (V) 3 For the third period of aircraft speed, V 2 For the second period of aircraft speed, V 1 The aircraft speed is the first period, and T is the software running period;
calculation of a 0 ～a 9 Sum is a m The steady state deceleration is averaged, i.e. as the current deceleration:
a v ＝(a m -a max -a min )/8； (4)
wherein a is 0 ～a 9 For an average deceleration rate of 10 times calculated within 0.3s, a max For maximum average deceleration rate, a min Is the minimum average deceleration rate.
3. The method for controlling braking based on variable load of an aircraft according to claim 2, wherein: the high speed section, the medium speed section and the low speed section of the airplane speed section are respectively 220km/h, 70 km/h-220 km/h and 25 km/h-70 km/h.
4. A method of braking control based on aircraft variable load according to claim 3, wherein: setting the whole process deceleration rate target of a certain braking working condition as a, wherein the deceleration rate target of each aircraft speed section is as follows: a+Δa 0 ，Δa 0 Is the change value of the target deceleration rate under the variable load of the airplane.
5. The method for controlling braking based on variable load of an aircraft according to claim 4, wherein: when the aircraft speed is more than 220km/h or 25 km/h-70 km/h, delta a 0 < 0; within other speed range Δa 0 ≥0。
6. The method for controlling braking based on variable load of aircraft according to claim 5, whereinThe method comprises the following steps: when the aircraft speed is 70 km/h-220 km/h, the target deceleration rate range is controlled to be a+delta a 0 And a f -between 2, a f Is an anti-slip entry threshold.
7. The method for controlling braking based on variable load of an aircraft according to claim 6, wherein: the comparison result of the current deceleration rate and the deceleration rate target range and the brake pressure control law are specifically that,
if a is v ＜a+Δa 0 Braking pressure P S Increasing to a target range at a rate of 1 MPa/s;
if a is v ＞a f -Δa 0 Braking pressure P S Reducing to a target range at a rate of 2 MPa/s;
if a is f -2≥a v ≥a+Δa 0 Maintaining the brake pressure;
and after the anti-slip failure, the pressure is restored to the rated braking pressure.
8. The utility model provides a brake control system based on aircraft variable load which characterized in that: the brake unit is used for applying and adjusting brake pressure to the wheel; the sensor unit is arranged on the machine wheel and used for detecting the rotation speed and the load of the machine wheel; the control unit acquires signals of the sensor unit and the calculation unit and sends a control instruction to the brake unit; a calculation unit for performing the calculation in the aircraft variable load based brake control method according to any one of claims 1 to 7.
9. The aircraft variable load based brake control system of claim 8, wherein: the control unit includes at least one processor, and a memory communicatively coupled to the at least one processor; wherein the memory stores a computer program executable by the at least one processor to enable the at least one processor to perform the aircraft variable load based brake control method of any one of claims 1-7.
10. An aircraft comprising the aircraft variable load based brake control system of any one of claims 7 or 8.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311354504.9A CN117261846A (en) | 2023-10-19 | 2023-10-19 | Brake control method and system based on aircraft variable load |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311354504.9A CN117261846A (en) | 2023-10-19 | 2023-10-19 | Brake control method and system based on aircraft variable load |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117261846A true CN117261846A (en) | 2023-12-22 |
Family
ID=89212324
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311354504.9A Pending CN117261846A (en) | 2023-10-19 | 2023-10-19 | Brake control method and system based on aircraft variable load |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117261846A (en) |
-
2023
- 2023-10-19 CN CN202311354504.9A patent/CN117261846A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1086173C (en) | System and method for adaptive brake application and initial skid detection | |
| CN101065280B (en) | Antiskid control - combined paired/individual wheel control logic | |
| CN101356085B (en) | Method and system to increase electric brake clamping force accuracy | |
| US9963224B2 (en) | Method for maximizing powered aircraft drive wheel traction | |
| CN102099230B (en) | Method of maintaining optimal braking and skid protection for a two-wheeled vehicle having a speed sensor failure on a single wheel | |
| EP1693262A1 (en) | Method and system to reduce carbon brake wear through residual brake force | |
| EP2899079B1 (en) | Optimized real-time antiskid control initialization for travel surfaces as a function of wheel spinup | |
| WO2004018274A1 (en) | System and method for adaptive brake application and initial skid detection | |
| CN104401305A (en) | Airplane brake control method | |
| CN103569130A (en) | Cornering control method for vehicle and cornering control system for vehicle | |
| CN111267573A (en) | Vehicle antiskid control method and system, computer readable storage medium and vehicle | |
| JPH11502165A (en) | Improvement of anti-lock braking system (ABS) for road vehicles | |
| CN117261846A (en) | Brake control method and system based on aircraft variable load | |
| CN113071457B (en) | Train antiskid control method and antiskid control device | |
| CN113044207B (en) | Method for improving safety of airplane antiskid brake system | |
| CN112987601B (en) | Unmanned aerial vehicle electromagnetic brake control system and method | |
| US10807579B2 (en) | System for maintaining near-peak friction of a braking wheel | |
| CN112959989B (en) | Real-time runway state detection method and brake pressure control method | |
| CN112623200B (en) | Brake control method for airplane skid resistance failure | |
| TWI718672B (en) | Brake control method based on the friction characteristics of the road | |
| CN114771475A (en) | Anti-skidding method and system in train braking process | |
| CN116620233A (en) | Braking control method for anti-skid faults of airplane | |
| CN115042962A (en) | Aircraft brake control system, landing gear, aircraft and aircraft brake method | |
| CN117799826A (en) | Airplane anti-skid brake control method based on slip rate control | |
| CN115675839A (en) | Antiskid braking system based on aircraft undercarriage vertical load |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |