CN-121973250-A - Gesture adjusting method of long cantilever motion mechanism

CN121973250ACN 121973250 ACN121973250 ACN 121973250ACN-121973250-A

Abstract

The invention discloses a gesture adjusting method of a long cantilever moving mechanism, which solves the problem that the position error of an end actuating mechanism is difficult to control due to the uncertainty of the parking gesture of an airplane, the manufacturing error of an adjusting mechanism and the large deflection of a long cantilever, ensures that the theoretical axis of the motion track planning of the long cantilever moving mechanism is matched with the actual air inlet channel axis, and avoids the collision of the long cantilever moving mechanism with the air inlet channel in the spraying operation process of the air inlet channel.

Inventors

LIANG JIE
GAO MENG
TANG KAI
LIU DAWEI
CHEN YAHUI
WANG FEI
HUANG JINGJIN
LUO LINGLING
TU FUQUAN
LEI PEI
JIANG WEI

Assignees

成都飞机工业（集团）有限责任公司

Dates

Publication Date: 20260505
Application Date: 20260407

Claims (9)

1. The gesture adjusting method of the long cantilever motion mechanism is characterized by comprising the following steps of: Step 1, establishing a reference coordinate system at a calibration position, and fitting a telescopic axis of a long cantilever motion mechanism under the reference coordinate system; step 2, measuring actual measurement coordinates of the aircraft air inlet characteristic points under a reference coordinate system, measuring theoretical coordinates of the aircraft air inlet characteristic points under the aircraft coordinate system, and calculating a mapping relation between the aircraft coordinate system and the reference coordinate system based on the actual measurement coordinates and the theoretical coordinates; step 3, extracting a theoretical axis of the air inlet channel of the aircraft under the aircraft coordinate system, and converting the theoretical axis into an actual axis under the reference coordinate system based on the mapping relation; step 4, calibrating a revolute pair and a movable pair in the long cantilever motion mechanism to obtain an adjustment relation among a rotation axis of the revolute pair, a movement axis of the movable pair and a telescopic axis of the long cantilever motion mechanism; Step 5, solving adjustment amounts of a revolute pair and a movable pair based on the position difference between the telescopic axis of the long cantilever motion mechanism and the actual axis of the air inlet channel of the airplane under a reference coordinate system; And 6, after the revolute pair and the movable pair are adjusted according to the adjustment amount each time, repeating the steps 1-5 until the deviation value between the actual pose and the target pose of the long cantilever movement mechanism reaches the standard.
2. The posture adjustment method of the long cantilever motion mechanism according to claim 1, wherein the step 4 specifically includes: Step 4.1, extracting a forward limit position and a reverse limit position of the revolute pair in the pitching direction and the revolving direction, selecting a plurality of intermediate process points in an equidistant interpolation manner between the forward limit position and the reverse limit position, and measuring coordinates of the intermediate process points; Step 4.2, obtaining a spherical surface based on coordinate fitting of the intermediate process points, and extracting the spherical center of the spherical surface as the rotation center of the revolute pair in the pitching direction and the revolving direction; Step 4.3, selecting intermediate process points with the same positions of the rotating shafts to fit to obtain a circumference, extracting a perpendicular line of the circumference passing through the rotating center, and performing least square fitting to obtain a pitching rotating axis; step 4.4, selecting intermediate process points with the same pitch axis position to fit to obtain a circumference, extracting a perpendicular line of the circumference passing through a rotation center, and performing least square fitting to obtain a rotation axis; and 4.5, extracting a forward limit position and a reverse limit position of the mobile pair in the current moving direction, selecting a plurality of intermediate process points in an equidistant interpolation manner between the forward limit position and the reverse limit position, and obtaining a moving axis based on fitting of the intermediate process points.
3. The posture adjustment method of the long cantilever motion mechanism according to claim 2, wherein the step 5 specifically includes: Step 5.1, calibrating a pitching revolute pair, and calculating pitching adjustment quantity of the pitching revolute pair according to the fact that the component of a direction vector of a telescopic axis of a long cantilever motion mechanism, which passes through the pitching revolute pair, on a revolving motion axis is equal to the component of an actual axis of an air inlet channel of an airplane on the revolving motion axis; 5.2, calibrating the revolute pair, namely projecting a direction vector of a telescopic axis of the long cantilever motion mechanism after the telescopic axis passes through the pitching revolute pair to be rotated to a first plane perpendicular to the direction vector to obtain a cantilever projection vector; and 5.3, calculating an axis equation of the telescopic axis of the long cantilever motion mechanism after the telescopic axis passes through the pitching revolute pair and the revolving revolute pair, and calibrating the movement adjustment amounts of the movable pair in the X axis, the Y axis and the Z axis of the reference coordinate system based on the axis equation.
4. The attitude adjusting method of a long cantilever motion mechanism according to claim 3, wherein in the step 5.1, the calculation formula of the pitch adjustment amount is as follows: ; Wherein: Representing the pitch adjustment amount; A unit direction vector representing an axis of an aircraft inlet; A unit direction vector representing the telescopic axis of the long cantilever motion mechanism; A unit direction vector representing a pitch axis; a unit direction vector representing the axis of rotation.
5. The method for adjusting the posture of the long cantilever motion mechanism according to claim 4, wherein in the step 5.2, the calculation formula of the rotation adjustment amount is as follows: ; Establishing a first plane of unit direction vectors perpendicular to the axis of rotation; Wherein: indicating the rotation adjustment amount; an air inlet projection vector representing a unit direction vector projection of an axis of an air inlet of the aircraft onto a first plane; The cantilever projection vector representing the projection of the unit direction vector of the telescopic axis of the long cantilever motion mechanism onto the first plane.
6. The method for adjusting the posture of the long cantilever motion mechanism according to claim 4, wherein in the step 5.3, the calculation formula of the rotation adjustment amount is as follows: Establishing an equation set: ; Wherein: the X-axis direction of the reference coordinate system is the X-axis direction of the moving pair, the Y-axis direction of the reference coordinate system is the Y-axis direction of the moving pair is the Y-axis direction of the reference coordinate system, and the Z-axis direction of the reference coordinate system is the Z-axis direction of the moving pair; a unit direction vector representing the X-axis of the reference coordinate system; a unit direction vector representing a Y-axis of the reference coordinate system; A unit direction vector representing the Z axis of the reference coordinate system; representing the total kinematic pair adjustment vector in the reference coordinate system.
7. The posture adjustment method of a long cantilever motion mechanism according to any one of claims 1-6, wherein the step 1 specifically includes: step 1.1, establishing a reference coordinate system, fixing a target ball at the tail end of a long cantilever motion mechanism, and measuring the spherical center coordinate of the target ball in an initial state that the long cantilever motion mechanism is completely retracted; step 1.2, controlling the tail end of the long cantilever motion mechanism to sequentially extend out of a fixed distance according to a set step length, and measuring the spherical center coordinates of the target ball when each extension is performed; and 1.3, establishing a parameter equation of the telescopic axis of the long cantilever motion mechanism based on the spherical center coordinates of the target ball.
8. The method for adjusting the posture of the long cantilever motion mechanism according to claim 7, wherein the step 2 specifically comprises: Step 2.1, selecting at least three different axial characteristic points on the surface of an aircraft air inlet, and extracting theoretical coordinates of the characteristic points under an aircraft coordinate system; Step 2.2, measuring actual measurement coordinates of the characteristic points under a reference coordinate system by using a laser tracker; And 2.3, matching the theoretical coordinates and the measured coordinates of the same feature point, and establishing a mapping relation between the aircraft coordinate system and the reference coordinate system.
9. The posture adjustment method of the long cantilever motion mechanism according to claim 8, wherein the step 3 specifically includes: step 3.1, importing a three-dimensional model of an aircraft air inlet into three-dimensional model software, and measuring a linear equation of an axis of the aircraft air inlet under an aircraft coordinate system in the three-dimensional model software; and 3.2, solving a linear equation of the axis of the air inlet channel of the aircraft in the reference coordinate system based on the mapping relation between the aircraft coordinate system and the reference coordinate system.

Description

Gesture adjusting method of long cantilever motion mechanism Technical Field The invention belongs to the technical field of gesture adjustment of a motion mechanism, and particularly relates to a gesture adjustment method of a long cantilever motion mechanism. Background The length-diameter ratio of the aircraft air inlet is large, the internal space is narrow, the cross section shape is irregular, the six-axis industrial spraying robot cannot be directly adopted for automatic spraying operation, and a long cantilever movement mechanism is required to enter the air inlet to finish spraying of the inner surface of the air inlet. According to the aircraft manufacturing process requirements, the air inlet channel needs to be sprayed in a complete machine state. Due to the differences of aircraft manufacturing and different air pressures of aircraft tires, the parking positions are uncertain, the long cantilever movement mechanism needs to have the capability of adjusting the pose, the theoretical axis of the movement track planning of the long cantilever movement mechanism is ensured to be matched with the actual air inlet channel axis, and the long cantilever mechanism is prevented from colliding with the air inlet channel in the process of spraying operation of the air inlet channel. Since the cantilever length of the long cantilever mechanism is usually more than 5 meters, the precision of the tail end of the long cantilever is very sensitive to angular deviation, and the precision of the tail end is difficult to be effectively ensured by virtue of a high-precision encoder at the rotating shaft. Meanwhile, the flexible deformation of the cantilever is difficult to measure, and the precision of the tail end of the long cantilever can be influenced. Therefore, how to ensure the precision of the long cantilever end in the whole spraying process is the biggest problem to be solved by the gesture adjustment. The invention discloses a gesture adjusting method of a long cantilever motion mechanism, which aims to solve the problem that the gesture adjusting precision of the tail end of the long cantilever is difficult to control in the prior art. Disclosure of Invention The invention discloses a posture adjusting method of a long cantilever motion mechanism, which can accurately adjust the posture of the tail end of the long cantilever motion mechanism. The invention is realized by the following technical scheme: A posture adjusting method of a long cantilever motion mechanism comprises the following steps: Step 1, establishing a reference coordinate system at a calibration position, and fitting a telescopic axis of a long cantilever motion mechanism under the reference coordinate system; step 2, measuring actual measurement coordinates of the aircraft air inlet characteristic points under a reference coordinate system, measuring theoretical coordinates of the aircraft air inlet characteristic points under the aircraft coordinate system, and calculating a mapping relation between the aircraft coordinate system and the reference coordinate system based on the actual measurement coordinates and the theoretical coordinates; step 3, extracting a theoretical axis of the air inlet channel of the aircraft under the aircraft coordinate system, and converting the theoretical axis into an actual axis under the reference coordinate system based on the mapping relation; step 4, calibrating a revolute pair and a movable pair in the long cantilever motion mechanism to obtain an adjustment relation among a rotation axis of the revolute pair, a movement axis of the movable pair and a telescopic axis of the long cantilever motion mechanism; Step 5, solving adjustment amounts of a revolute pair and a movable pair based on the position difference between the telescopic axis of the long cantilever motion mechanism and the actual axis of the air inlet channel of the airplane under a reference coordinate system; And 6, after the revolute pair and the movable pair are adjusted according to the adjustment amount each time, repeating the steps 1-5 until the deviation value between the actual pose and the target pose of the long cantilever movement mechanism reaches the standard. In order to better implement the present invention, further, the step 4 specifically includes: Step 4.1, extracting a forward limit position and a reverse limit position of the revolute pair in the pitching direction and the revolving direction, selecting a plurality of intermediate process points in an equidistant interpolation manner between the forward limit position and the reverse limit position, and measuring coordinates of the intermediate process points; Step 4.2, obtaining a spherical surface based on coordinate fitting of the intermediate process points, and extracting the spherical center of the spherical surface as the rotation center of the revolute pair in the pitching direction and the revolving direction; Step 4.3, selecting intermediate process po