CN111553023B - Method for determining direct link control law of telex helicopter - Google Patents
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- CN111553023B CN111553023B CN202010362841.2A CN202010362841A CN111553023B CN 111553023 B CN111553023 B CN 111553023B CN 202010362841 A CN202010362841 A CN 202010362841A CN 111553023 B CN111553023 B CN 111553023B
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Abstract
The invention belongs to the technical field of fly-by-wire flight control systems of helicopters, and relates to a method for determining a direct link control law of a fly-by-wire helicopter, which comprises the following steps: determining parameters required by a direct link control law, wherein the fixed parameters comprise the range of each channel control lever, the variable pitch range of each channel control surface, the pitch angle of each channel variable pitch reference position and the travel range of each executing mechanism, and the calculation process parameters are as follows: the transmission ratio from each channel control rod to the control surface, the transmission ratio from each channel control surface to the actuating mechanism and the coupling coefficient among the channels; establishing a direct link control law simulation model according to the direct link control law parameters; the method for determining the direct link control law of the helicopter is characterized in that a relation model among channels is built through Simulink, the display is visual, the design optimization is facilitated, and accurate theoretical verification can be performed.
Description
Technical Field
The invention belongs to the technical field of fly-by-wire flight control systems of helicopters, and relates to a method for determining a direct link control law of a fly-by-wire helicopter.
Background
The direct link mode is a control mode of a fly-by-wire helicopter flight control system, and is equivalent to a mechanical lever system control mode of a traditional flight control system. The steering relationship of the club head to the actuator of conventional steering systems is achieved through the design of mechanical components. In the fly-by-wire helicopter, the cable replaces a mechanical linkage from the club head to the actuator, so that a direct link control law needs to be designed to realize the manipulation relationship from the club head to the actuator in a direct link mode.
Disclosure of Invention
The purpose of the invention is: a method for determining the direct link control law of a fly-by-wire helicopter is provided to realize the control relationship from a club head to an actuator in a direct link mode.
In order to solve the technical problem, the technical scheme of the invention is as follows:
a method for determining the direct link control law of a helicopter,
comprises the following steps:
determining parameters required by a direct link control law, wherein the parameters comprise fixed parameters and process parameters, and the fixed parameters refer to inherent design parameters of a helicopter;
the process parameters are as follows: the transmission ratio of the control rod of each channel to the control surface, the transmission ratio of the control surface of each channel to the actuating mechanism, the coupling coefficient among the channels and the stroke range of each actuating mechanism.
Step two, calculating process parameters:
2.1, calculating the transmission ratio from the control lever to the control surface;
calculating the transmission ratio from the control lever to the control surface according to the control lever range and the control surface variable distance range of each channel;
2.2, calculating the transmission ratio from the control surface to the actuating mechanism;
respectively calculating the transmission ratio from the pitch angle of the main blades of the pitching channel, the rolling channel and the total pitch channel to each main blade steering engine;
calculating the transmission ratio from the variable pitch angle of the tail rotor to the steering engine of the tail rotor;
2.3, determining the coupling coefficient among the channels;
2.4, calculating the stroke range of each actuating mechanism;
calculating the travel range of each actuating mechanism according to the variable pitch range of the control surface of each channel and the transmission ratio from the control surface to the actuating mechanism;
step three, establishing a direct link control law simulation model according to the direct link control law parameters;
3.1, determining input and output of the model;
the input is the operating lever stroke of four channels, and the output is the stroke of a main paddle steering engine and a tail paddle steering engine;
3.2, determining the relationship among the parameters of the direct link control law of each channel:
3.2.1, from the input, after amplitude limiting is carried out in the range of the operating lever, amplifying the K ratio, and superposing A;
3.2.2, after amplitude limiting is carried out in the control surface variable pitch range, superposing-A, carrying out K1 proportional amplification, and superposing K2;
3.2.3, limiting the amplitude through the stroke range controlled by the actuating mechanism and outputting;
k is the transmission ratio from the control lever to the control surface, and A is the pitch angle of the variable pitch reference position; k1 is the current lane control surface to actuator gear ratio and K2 is the other lane control surface to actuator gear ratio.
The fixed parameters are: the range of each channel control lever, the range of each channel control surface variable pitch, and the pitch angle of each channel variable pitch reference position.
And step two 2.2, respectively calculating the transmission ratio from the pitch angle of the main blades of the pitch, roll and collective pitch channels to each main blade steering engine according to the arrangement form of the main blade steering engines, the parameters of the automatic inclinators and the parameters of the hubs.
And step two 2.2, calculating the transmission ratio from the tail rotor variable pitch angle to the tail rotor steering engine according to the parameters of the tail rotor hub.
Each channel is four channels of pitching, rolling, course and total distance.
The coupling coefficient between the channels is determined as follows:
determining the coupling coefficient of the other channels to the current channel according to the coupling relation of the other channels to the current channel;
and determining the coupling coefficient of the current channel to other channels according to the coupling relation of the current channel to other channels.
Step three, 3.2.1, also comprises the following operations:
if the coupling relation of the current channel to other channels exists, before the K proportion is amplified, L2 is superposed to the other channels;
if the coupling relation of other channels to the current channel exists, after the K proportion is amplified, L1 is superposed to the current channel;
l1 is the coupling coefficient of the current channel to the other channels, and L2 is the coupling coefficient of the current channel to the other channels.
Preferably, the establishing of the direct-link control law simulation model in the third step is performed by Simulink.
The invention has the beneficial effects that:
the method provides a design method of a direct link control law, builds a relation model among channels through Simulink, is visual in display, is convenient for design optimization, and can carry out accurate theoretical verification.
The method is applied to the design of the fly-by-wire flight control system of the Z-TA helicopter, has good effect and higher use value.
Drawings
In order to more clearly illustrate the technical solution of the present invention, the drawings used in the embodiment of the present invention will be briefly explained. It is obvious that the drawings described below are only some embodiments of the invention, and that for a person skilled in the art, other drawings can be obtained from these drawings without inventive effort.
FIG. 1 is a block diagram of a direct link control law modeling for a channel using the method of the present invention;
where K is the transmission ratio of the joystick to the control surface,
k1-control surface to actuator gear ratio,
k2-ratio of other channel control surfaces to actuators,
l1 — coupling coefficients of other channels to this channel,
l2 — the coupling coefficient of this channel to the other channels,
a-pitch angle of the pitch reference position,
s1-limiting the joystick range,
s2-clipping the control surface pitch range,
s3 limiting the stroke range of the actuator.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. It is to be understood that the embodiments described are only a few embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Features of various aspects of embodiments of the invention will be described in detail below. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent, however, to one skilled in the art that the present invention may be practiced without these specific details. The following description of the embodiments is merely intended to better understand the present invention by illustrating examples thereof. The present invention is not limited to any particular arrangement or method provided below, but rather covers all product structures, any modifications, alterations, etc. of the method covered without departing from the spirit of the invention.
In the drawings and the following description, well-known structures and techniques are not shown to avoid unnecessarily obscuring the present invention. The method steps of the invention are described in detail below by taking a certain helicopter as an example:
1. the parameters required for determining the direct link control law should include:
a. fixing parameters:
the fixed parameter definition of each channel control lever range, each channel control surface variable-pitch range, each channel variable-pitch reference position and course channel is shown in table 1;
TABLE 1 course channel fixed parameters
| (Code) | Parameter(s) | Numerical value |
| S1 | Operating lever range mm | -70～+30 |
| S2 | Control surface variable range ° | -10～+20 |
| A | Pitch angle of variable pitch reference position ° | 5 |
b. The process parameters are as follows:
the transmission ratio of the control rod of each channel to the control surface, the transmission ratio of the control surface of each channel to the actuating mechanism, the coupling coefficient among the channels and the stroke range of each actuating mechanism. The course parameters of the course channel are shown in Table 2:
TABLE 2 course channel Process parameters
| (Code) | Parameter(s) |
| K | Joystick to control surface ratio |
| K1 | Control surface to tail rotor steering engine transmission ratio |
| K2 | Ratio of other channel control surface to tail rotor steering engine |
| L2 | Course to lateral channel coupling coefficient |
| L1 | Coupling coefficient of total distance to course channel |
| S3 | Range of travel of tail rotor steering engine |
2. And calculating the process parameters.
a. Joystick to control surface ratio
Calculating the transmission ratio from the control lever to the control surface according to the range of the course control lever and the range of the control surface variable pitch as follows:
k is S2 algebraic sum/S1 algebraic sum is 0.3 degree/mm
b. Control surface to actuator gear ratio
Calculating the transmission ratio from the tail rotor variable pitch angle to the tail rotor steering engine according to the parameters of the tail rotor hub as follows:
the radius of the tail rotor variable-pitch rocker arm is 110 mm;
K1＝sin(π/180)×110＝1.92mm/°
the other three channel control surfaces have no control relation to the tail rotor steering engine, so the transmission ratio is 0.
c. Coefficient of coupling
a) Determining a coupling coefficient of the collective pitch channel to the course channel according to the coupling relation of the collective pitch channel to the course channel; the parameter of the coupling relation of the total distance to the course is 1 degree/degree;
the transmission ratio from the total distance control rod to the control surface is 0.05 degrees/mm;
L1＝0.05×1＝0.05°/mm
b) and determining the coupling coefficient of the course channel to the transverse channel according to the coupling relation of the course channel to the transverse channel.
The coupling relation parameter of the course to the transverse direction is 0.2 degrees/degree;
L2＝K×0.2＝0.06°/mm
d. range of travel of actuator
And calculating the stroke of the tail rotor steering engine according to the transmission ratio from the tail rotor variable-pitch angle to the tail rotor steering engine and the variable-pitch range of the control surface.
K1 XS 2 algebraic sum of S3-57.6 mm
The S3 is calculated to be-28.8 mm- +28.8mm
3. Establishing a direct link control law simulation model according to the direct link control law parameters;
the direct link control law comprises parameter relations of four channels of pitching, rolling, course and total distance, and parameter relation block diagrams of all the channels are combined together to form the direct link control law.
a. The control rod strokes of the four channels are input;
b. the strokes of the main propeller steering engine and the tail propeller steering engine are output;
the relationship between the parameters of the direct link control law of the course channel is as follows:
c. carrying out amplitude limiting through S1 at the beginning of input, carrying out K-scale amplification, and superposing A and L1;
while superimposing L2 to the transverse channel before K-scale up;
d. limiting amplitude through S2, superposing-A, amplifying the K1 proportion, and superposing K2;
clipping is performed through S3, and the output ends.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solutions of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive various equivalent modifications or substitutions within the technical scope of the present invention, and these modifications or substitutions should be covered within the scope of the present invention.
Claims (8)
1. A method for determining the direct link control law of a helicopter-by-wire helicopter is characterized by comprising the following steps: the method for determining the direct link control law of the fly-by-wire helicopter comprises the following steps:
determining parameters required by a direct link control law, wherein the parameters comprise fixed parameters and process parameters, and the fixed parameters refer to inherent design parameters of a helicopter;
the process parameters are as follows: the transmission ratio from each channel control rod to the control surface, the transmission ratio from each channel control surface to the actuating mechanism, the coupling coefficient among the channels and the stroke range of each actuating mechanism;
step two, calculating process parameters:
2.1, calculating the transmission ratio from the control lever to the control surface;
calculating the transmission ratio from the control lever to the control surface according to the control lever range and the control surface variable distance range of each channel;
2.2, calculating the transmission ratio from the control surface to the actuating mechanism;
respectively calculating the transmission ratio from the pitch angle of the main blades of the pitching channel, the rolling channel and the total pitch channel to each main blade steering engine;
calculating the transmission ratio from the variable pitch angle of the tail rotor to the steering engine of the tail rotor;
2.3, determining the coupling coefficient among the channels;
2.4, calculating the stroke range of each actuating mechanism;
calculating the travel range of each actuating mechanism according to the variable pitch range of the control surface of each channel and the transmission ratio from the control surface to the actuating mechanism;
step three, establishing a direct link control law simulation model according to the direct link control law parameters;
3.1, determining input and output of the model;
the input is the operating lever stroke of four channels, and the output is the stroke of a main paddle steering engine and a tail paddle steering engine;
3.2, determining the relationship among the parameters of the direct link control law of each channel:
3.2.1, from the input, after amplitude limiting is carried out in the range of the operating lever, amplifying the K ratio, and superposing A;
3.2.2, after amplitude limiting is carried out in the control surface variable pitch range, superposing-A, carrying out K1 proportional amplification, and superposing K2;
3.2.3, limiting the amplitude through the stroke range controlled by the actuating mechanism and outputting;
k is the transmission ratio from the control lever to the control surface, and A is the pitch angle of the variable pitch reference position; k1 is the current lane control surface to actuator gear ratio and K2 is the other lane control surface to actuator gear ratio.
2. Method for determining the direct link control law for helicopter according to claim 1, characterized in that: the fixed parameters are: the range of each channel control lever, the range of each channel control surface variable pitch, and the pitch angle of each channel variable pitch reference position.
3. Method for determining the direct link control law for helicopter according to claim 1, characterized in that: in the second step:
and respectively calculating the transmission ratio from the pitch angle of the main blades of the pitching channel, the rolling channel and the total pitch channel to each main blade steering engine according to the arrangement form of the main blade steering engines, the parameters of the automatic inclinator and the parameters of the hub.
4. Method for determining the direct link control law for helicopter according to claim 1, characterized in that: in the second step:
and calculating the transmission ratio from the variable pitch angle of the tail rotor to the steering engine of the tail rotor according to the parameters of the hub of the tail rotor.
5. Method for determining the direct link control law for helicopter according to claim 1, characterized in that: the channels refer to: pitching, rolling, course and total distance.
6. Method for determining the direct link control law for helicopter according to claim 1, characterized in that: the determination mode of the coupling coefficient among the channels in the step two is as follows:
determining the coupling coefficient of the other channels to the current channel according to the coupling relation of the other channels to the current channel;
and determining the coupling coefficient of the current channel to other channels according to the coupling relation of the current channel to other channels.
7. Method for determining the direct link control law for helicopter according to claim 1, characterized in that: the third step 3.2.1 further comprises the following operations:
if the coupling relation of the current channel to other channels exists, before the K proportion is amplified, L2 is superposed to the other channels;
if the coupling relation of other channels to the current channel exists, after the K proportion is amplified, L1 is superposed to the current channel;
l1 is the coupling coefficient of the current channel to the other channels, and L2 is the coupling coefficient of the current channel to the other channels.
8. Method for determining the direct link control law for helicopter according to claim 1, characterized in that: and establishing a direct link control law simulation model in the third step through Simulink.
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Inventor after: Deng Jinghui Inventor after: Deng Haixia Inventor after: Sun Chong Inventor after: Feng Hang Inventor before: Deng Haixia Inventor before: Sun Chong Inventor before: Feng Hang |