Automatic digging force testing system and method for excavator

Abstract

The present invention relates to the technical field of excavator digging force testing, and specifically discloses an automatic digging force testing system and method for excavators, which obtains excavator parameters and determines the excavator posture through an instrument controller, automatically or manually inputs the length information of the three oil cylinders of the boom oil cylinder, the dipper rod oil cylinder, and the bucket oil cylinder into the vehicle controller, and the vehicle controller performs calculations, and the pull rope is automatically adjusted to the specified position; then the bucket and the dipper rod are slowly adjusted, and after the main pump overflows, the sensor feeds back the test data to the vehicle controller, and the vehicle controller feeds back the data to the instrument controller, and the instrument controller records it after judging that it is qualified, and if it is unqualified, it continues to input the length information of the three oil cylinders until all the test data are qualified. The present invention solves the problem that the prior art cannot accurately test the tangential force of the excavator and the testing process is cumbersome, and the present invention can automatically complete the digging force test and realize unmanned testing of the excavator digging force.

Description

Technical Field

[0001] The invention belongs to the technical field of excavator digging force testing, and in particular relates to an automatic digging force testing system for an excavator. The invention also provides a testing method for the system. Background Art

[0002] Hydraulic excavators are one of the most widely used equipment in earth-moving machinery. The digging force can directly reflect the performance of an excavator. The digging force is divided into bucket digging force and arm digging force, and a composite digging force can also be generated at the same time; at the same time, the change in the digging posture of the working device also affects the size of the digging force. The existing technology completely relies on human eyes or manual measurement, which cannot accurately test the digging tangential force, and the testing process is cumbersome.

[0003] Chinese invention patent CN 102995673 A discloses a rope positioning control method for excavator digging force testing, including: obtaining the posture information of the boom, dipper arm and bucket according to the detection results of the sensor; determining the excavation trajectory according to the posture information; determining the anchoring position of the rope on the anchor frame with the tooth root of the bucket as the tangent point and set along the tangent direction of the excavation trajectory according to the excavation trajectory. In the technical solution of this invention, sensors are used to detect the posture information of the boom, dipper arm and bucket, and the control device determines the excavation trajectory according to the posture information and finally obtains the anchoring position of the rope on the anchor frame. This invention only briefly introduces that this method can be used to position the rope and test the digging force, and does not provide a specific method for how to test the digging force. Summary of the invention

[0004] In order to overcome the defects of the prior art that the tangential force of the excavator cannot be accurately tested and the testing process is cumbersome, the present invention provides an automatic excavator digging force testing system and method that only needs to collect cylinder pressure, displacement, and tension, communicate with the vehicle controller through an instrument controller, and click start to automatically complete the digging force test, thereby realizing unmanned testing.

[0005] The technical solution adopted by the present invention to achieve the above-mentioned purpose is:

[0006] An automatic digging force testing system for an excavator comprises:

[0007] The instrument controller is used to obtain the working device parameters of the excavator, judge the test posture of the excavator according to the working device parameters, obtain the three cylinder length information of the boom cylinder, the dipper arm cylinder and the bucket cylinder after judging the test posture of the excavator, and send the automatic test start instruction and the three cylinder length information to the vehicle controller at the same time; receive the test data sent by the vehicle controller and make a judgment, and record the bucket digging force and dipper arm digging force data after judging that it is qualified; if it is unqualified, continue to send the three cylinder length information to the vehicle controller until the test data recording is qualified;

[0008] After the vehicle controller receives the three cylinder length information and automatic test instructions sent by the instrument controller, the automatic digging force test program starts to work. The maximum digging force cylinder length program calculates the arm's relative movement angle a to the slewing platform, the arm's relative movement angle b, the bucket's relative movement angle c, and the height and angle that the pull rope should be adjusted. The pull rope is automatically adjusted to the specified position. At the same time, the test data sent by the sensor is fed back to the instrument controller.

[0009] The sensor is used to collect test data when the main pump overflows during the slow loading process of the bucket cylinder and the stick cylinder, and send the test data to the vehicle controller.

[0010] The excavator test posture includes a maximum digging force test posture and a normal test posture; if the excavator test posture is the maximum digging force posture, the three cylinder lengths of the boom cylinder, the dipper arm cylinder, and the bucket cylinder in the maximum digging force posture are automatically calculated through the instrument controller; if the test posture is the normal posture or the instrument controller determines that the test data is unqualified, the three cylinder lengths of the boom cylinder, the dipper arm cylinder, and the bucket cylinder need to be manually input.

[0011] Furthermore, the test data includes pressure, displacement and tension data of the boom cylinder, the arm cylinder and the bucket cylinder.

[0012] Furthermore, the sensors include a wire displacement sensor installed on the boom cylinder, the dipper cylinder and the bucket cylinder, a pressure sensor, and a dynamometer sensor installed between the ground anchor and the bucket.

[0013] The present invention also provides an automatic digging force testing method for an excavator, comprising the following steps:

[0014] (1) Determine the test posture through the instrument controller, obtain the lengths of the three cylinders: the boom cylinder, the arm cylinder, and the bucket cylinder, and send the data to the vehicle controller;

[0015] (2) The vehicle controller automatically calculates the angle a of the boom relative to the slewing platform, the angle b of the arm relative to the boom, the angle c of the bucket relative to the arm, and the height and angle of the pull rope to be adjusted, and the pull rope is automatically adjusted to the specified position;

[0016] (3) During the slow loading of the bucket cylinder and the boom cylinder, after the main pump overflows, the sensor feeds back the test data to the vehicle controller, and the vehicle controller transmits the test data to the instrument controller;

[0017] (4) The instrument controller makes a judgment and records the bucket digging force and dipper arm digging force data if they are qualified; if they are unqualified, the lengths of the boom cylinder, dipper arm cylinder, and bucket cylinder are sent to the vehicle controller, and the process of (2), (3), and (4) is repeated until the data are judged to be qualified and the recording is completed.

[0018] Furthermore, the length information of the three oil cylinders is obtained by selecting one of the following methods according to the test posture of the excavator:

[0019] (1) If the excavator test posture is the maximum digging force posture, the instrument controller automatically calculates the lengths of the three cylinders under the maximum digging force posture;

[0020] (2) If the test posture is normal or the instrument controller determines that the test data is unqualified, you need to manually enter the three cylinder lengths.

[0021] Furthermore, the steps for automatically calculating the lengths of the three cylinders at the maximum digging force posture by the instrument controller are as follows:

[0022] When the model and working device size of the excavator are known, a two-dimensional coordinate system is established with the intersection of the rotation center and the horizontal line as the origin o of the absolute coordinate system, the positive direction of the horizontal axis y is directly in front, and the positive direction of the vertical axis z is directly above. At the same time, in order to facilitate calculation, an AM point is set on the excavator working device for identification and coordinate point calculation. A represents the hinge point of the rear support of the boom, B represents the hinge point of the large cavity of the boom cylinder, B1 represents the negative translation point of the horizontal axis of point B, which does not represent the specific position and is only used for direction. C represents the middle support of the boom, that is, the hinge point of the small cavity of the boom cylinder, D represents the hinge point of the large cavity of the bucket cylinder, E represents the front support of the boom, that is, the hinge point of the rear support of the bucket, F represents the hinge point of the small cavity of the bucket cylinder, G represents the hinge point of the large cavity of the bucket cylinder, J represents the hinge point of the small cavity of the bucket cylinder, H represents the hinge point of the middle support of the bucket, K represents the hinge point of the front support of the bucket, that is, the hinge point of the rear ear plate of the bucket, L represents the hinge point of the front ear plate of the bucket, and M represents the tip of the bucket tooth;

[0023] Boom posture:

[0024] BC length is calculated from the smallest to the largest size of the boom cylinder, with a 1mm interval.

[0025] a=acos((AB^2+AC^2-BC^2) / (2*AB*AC))-∠EAC-∠ABB1;

[0026] Determine when a+∠EAC+∠ABB1 =π / 2;

[0027] Extract the current BC length;

[0028] Where: π represents pi, AB represents the distance between point A and point B, AC represents the distance between point A and point C, BC represents the length of the boom cylinder, that is, the distance between point B and point C, ∠EAC represents the angle formed by point E, point A, and point C, ∠ABB1 represents the angle formed by point A, point B, and point B1, and a represents the displacement angle of the boom relative to the platform;

[0029] Bucket posture:

[0030] GJ length is calculated from the smallest to the largest size of the bucket cylinder, with an interval of 1mm.

[0031] ∠GHJ=acos((GH^2+HJ^2-GJ^2) / (2*GH*HJ));

[0032] ∠JGH=acos((GH^2+GJ^2-HJ^2) / (2*GH*GJ));

[0033] ∠GJH=π-∠JGH-∠GHJ;

[0034] ∠JHK=∠GHK-∠GHJ;

[0035] JK=(HJ^2+HK^2-2*HJ*HK*cos(∠JHK))^0.5;

[0036] ∠JKL=acos((JK^2+KL^2-JL^2) / (2*JK*KL));

[0037] ∠JLK=acos((JL^2+KL^2-JK^2) / (2*JL*KL));

[0038] ∠JKH=acos((HK^2+JK^2-HJ^2) / (2*JK*HK));

[0039] ∠LJH=2π-∠JHK-∠JKH-∠JKL-∠JLK;

[0040] Fbucket=(pc*sc)*10^6;

[0041] Fwbucket=((Fbucket*sin(∠GJH) / sin(∠LJH))*sin(∠JLK)*KL) / (KM);

[0042] Where: GJ represents the length of the bucket cylinder, that is, the distance between point G and point J; ∠GHJ represents the angle formed by point G, point H, and point J; GH represents the distance between point G and point H; HJ represents the distance between point H and point J; ∠JGH represents the angle formed by point J, point G, and point H; ∠GJH represents the angle formed by point G, point J, and point H; ∠GHK represents the angle formed by point G, point H, and point K; ∠JHK represents the angle formed by point J, point H, and point K; JK represents the distance between point J and point K; HK represents the distance between point H and point K; ∠JKL represents the angle formed by point J, point K, and point L. The angle formed, KL represents the distance between point K and point L, JL represents the distance between point J and point L, ∠JLK represents the angle formed by point J, point L, and point K, ∠JKH represents the angle formed by point J, point K, and point H, ∠LJH represents the angle formed by point L, point J, and point H, Fbucket represents the bucket cylinder force, pc represents the pressure of the large chamber of the bucket cylinder; sc represents the area of ​​the large chamber of the bucket cylinder; KM represents the distance between point K and point M, Fwbucket represents the bucket digging force, find the maximum bucket digging force in the cycle, and extract the length of the posture GJ with the maximum bucket digging force;

[0043] Stick posture:

[0044] After determining GJ, calculate the maximum digging force of the bucket arm.

[0045] DF length is calculated from the smallest to the largest size of the boom cylinder, with an interval of 1mm.

[0046] ∠EFD=acos((DF^2+EF^2-ED^2) / (2*DF*EF));

[0047] Farm = (pa*sa)*10^6;

[0048] EM=(EK^2+KM^2-2*EK*KM*cos(π-c))^0.5;

[0049] Fwarm=(Farm*sin(∠EFD)*EF) / (EM);

[0050] Where: DF represents the length of the boom cylinder, that is, the distance between point D and point F; ∠EFD represents the angle formed by points E, F, and D; EF represents the distance between points E and F; ED represents the distance between points E and D; Farm represents the boom cylinder force; pa represents the large chamber pressure of the boom cylinder; sa represents the large chamber area of ​​the boom cylinder; EM represents the distance between points E and M; Fwarm represents the boom digging force; find the maximum boom digging force in the cycle, and extract the DF length of the maximum boom digging force posture;

[0051] In summary, the instrument controller automatically calculates the lengths of the three cylinders under the maximum digging force posture.

[0052] Furthermore, the vehicle controller calculates the displacement angle a of the boom relative to the platform through the maximum digging force cylinder length program:

[0053] a=acos((AB^2+AC^2-BC^2) / (2*AB*AC))-∠EAC-∠ABB1;

[0054] The displacement angle b of the bucket arm relative to the boom is calculated:

[0055] b=-(π-(2*π-∠AED-∠FEK-acos((ED^2+EF^2-DF^2) / (2*DE*EF))));

[0056] Where: ∠AED represents the angle formed by points A, E, and D; ∠FEK represents the angle formed by points F, E, and K;

[0057] The displacement angle c of the bucket relative to the dipper arm is calculated:

[0058] ∠GHJ=acos((GH^2+HJ^2-GJ^2) / (2*GH*HJ));

[0059] ∠JGH=acos((GH^2+GJ^2-HJ^2) / (2*GH*GJ));

[0060] ∠GJH=π-∠JGH-∠GHJ;

[0061] ∠JHK=∠GHK-∠GHJ;

[0062] JK=(HJ^2+HK^2-2*HJ*HK*cos(∠JHK))^0.5;

[0063] ∠JKL=acos((JK^2+KL^2-JL^2) / (2*JK*KL));

[0064] ∠JKH=acos((HK^2+JK^2-HJ^2) / (2*JK*HK));

[0065] c=-(π-(2*π-∠EKH-∠JKL-∠MKL-∠JKH));

[0066] The specific steps for calculating the height and angle that the pull rope should be adjusted are as follows:

[0067] Calculate the coordinate position of the front support of the boom, that is, the hinge point E of the rear support of the bucket arm:

[0068] Ye = AE*cos(a);

[0069] Ze = AE*sin(a);

[0070] Where: Ye represents the position of point E on the horizontal axis, Ze represents the position of point E on the vertical axis; AE represents the distance between point A and point E;

[0071] Calculate the coordinate position of point M at the bucket tooth tip:

[0072] Ym=EK*cos(a+b)+AE*cos(a)+KM*cos(a+b+c);

[0073] Zm=EK*sin(a+b)+AE*sin(a)+KM*sin(a+b+c);

[0074] In the formula, Ym represents the position of point M on the horizontal axis, and Zm represents the position of point M on the vertical axis;

[0075] Therefore, the fixing point of the pull rope on the ground anchor can be calculated;

[0076] The fixing point P2 of the digging force rope of the bucket arm on the ground anchor:

[0077] EM=((Ym-Ye)^2+(Zm-Ze)^2)^0.5;

[0078] ∠EMK=acos((EM^2+KM^2-EK^2) / (2*EM*KM));

[0079] P2 =MN2*sin(ab-c+π / 2+∠EMK)+Zm+L1;

[0080] Where, P2 represents the distance from the fixed point of the digging force rope of the bucket arm to the bottom of the pit, ∠EMK represents the angle formed by points E, M, and K, L1 represents the platform height, and MN2 represents the length of the rope under the digging force posture of the bucket arm;

[0081] Bucket digging force rope fixed point P1 on the ground anchor:

[0082] P1=L1- MN1*sin(b+c-a+π / 2)+Zm;

[0083] Where P1 represents the distance from the fixed point of the bucket digging force rope to the bottom of the pit, and MN1 represents the length of the rope in the bucket digging force posture.

[0084] The present invention obtains the parameters of the excavator working device and determines the excavator posture through the instrument controller. After determining the excavator posture, the length information of the three oil cylinders of the boom oil cylinder, the dipper rod oil cylinder and the bucket oil cylinder is automatically or manually input into the vehicle controller. The vehicle controller calculates the movement angle a of the boom relative to the rotary platform, the movement angle b of the dipper rod relative to the boom, the movement angle c of the bucket relative to the dipper rod, and the height and angle of the pull rope to be adjusted. The pull rope is automatically adjusted to the specified position; then the bucket and the dipper rod are slowly adjusted. After the main pump overflows, the sensor feeds back the test data to the vehicle controller, and the vehicle controller feeds back the data to the instrument controller. The instrument controller records it after judging that it is qualified. If it is unqualified, the length information of the three oil cylinders continues to be input until all the test data are qualified. In the test process, the present invention fully realizes the test of automatic excavation force. On the one hand, the excavation tangential force can be accurately obtained. On the other hand, the pull rope is adjusted in real time through the vehicle controller without manual adjustment of the pull rope. BRIEF DESCRIPTION OF THE DRAWINGS

[0085] The present invention will be further described below in conjunction with the accompanying drawings, in which:

[0086] Figure 1 This is a diagram of the automatic digging force test system for excavators;

[0087] Figure 2 This is a schematic diagram of the working status of the excavator;

[0088] Figure 3 The figure is a flow chart of the automatic digging force testing method for excavators. DETAILED DESCRIPTION

[0089] Example 1

[0090] like Figure 1 , 2 As shown, the automatic digging force testing system for an excavator of this embodiment includes:

[0091] The instrument controller is used to obtain the working device parameters of the excavator, judge the test posture of the excavator according to the working device parameters, obtain the three cylinder length information of the boom cylinder, the dipper arm cylinder and the bucket cylinder after judging the test posture of the excavator, and send the automatic test start instruction and the three cylinder length information to the vehicle controller at the same time; receive the test data sent by the vehicle controller and make a judgment, and record the bucket digging force and dipper arm digging force data after judging that it is qualified; if it is unqualified, continue to send the three cylinder length information to the vehicle controller until the test data recording is qualified;

[0092] After the vehicle controller receives the three cylinder length information and automatic test instructions sent by the instrument controller, the automatic digging force test program starts to work. The maximum digging force cylinder length program calculates the arm's relative movement angle a to the slewing platform, the arm's relative movement angle b, the bucket's relative movement angle c, and the height and angle that the pull rope should be adjusted. The pull rope is automatically adjusted to the specified position. At the same time, the test data sent by the sensor is fed back to the instrument controller.

[0093] The sensor is used to collect test data when the main pump overflows during the slow loading process of the bucket cylinder and the stick cylinder, and send the test data to the vehicle controller.

[0094] Furthermore, the excavator test posture includes a maximum digging force test posture and a normal test posture; if the excavator test posture is the maximum digging force posture, the three cylinder lengths of the boom cylinder, the dipper arm cylinder, and the bucket cylinder in the maximum digging force posture are automatically calculated through the instrument controller; if the test posture is the normal posture or the instrument controller determines that the test data is unqualified, the three cylinder lengths of the boom cylinder, the dipper arm cylinder, and the bucket cylinder need to be manually input, and the test data include the pressure, displacement, and tension data of the boom cylinder, the dipper arm cylinder, and the bucket cylinder.

[0095] Furthermore, the sensors include a wire displacement sensor installed on the boom cylinder, the dipper cylinder and the bucket cylinder, a pressure sensor, and a dynamometer sensor installed between the ground anchor and the bucket, and the sensors all adopt existing general models.

[0096] Example 2

[0097] An automatic digging force testing method for an excavator comprises the following steps:

[0098] (1) Determine the test posture through the instrument controller, obtain the lengths of the three cylinders: the boom cylinder, the arm cylinder, and the bucket cylinder, and send the data to the vehicle controller;

[0099] (2) The vehicle controller automatically calculates the angle a of the boom relative to the slewing platform, the angle b of the arm relative to the boom, the angle c of the bucket relative to the arm, and the height and angle of the pull rope to be adjusted, and the pull rope is automatically adjusted to the specified position;

[0100] (3) During the slow loading of the bucket cylinder and the boom cylinder, after the main pump overflows, the sensor feeds back the test data to the vehicle controller, and the vehicle controller transmits the test data to the instrument controller;

[0101] (4) The instrument controller makes a judgment and records the bucket digging force and dipper arm digging force data if they are qualified; if they are unqualified, the lengths of the boom cylinder, dipper arm cylinder, and bucket cylinder are sent to the vehicle controller, and the process of (2), (3), and (4) is repeated until the data are judged to be qualified and the recording is completed.

[0102] Furthermore, the length information of the three oil cylinders is obtained by selecting one of the following methods according to the test posture of the excavator:

[0103] (1) If the excavator test posture is the maximum digging force posture, the instrument controller automatically calculates the lengths of the three cylinders under the maximum digging force posture;

[0104] (2) If the test posture is normal or the instrument controller determines that the test data is unqualified, you need to manually enter the three cylinder lengths.

[0105] Furthermore, the steps for automatically calculating the lengths of the three cylinders at the maximum digging force posture by the instrument controller are as follows:

[0106] When the model and working device size of the excavator are known, a two-dimensional coordinate system is established with the intersection of the rotation center and the horizontal line as the origin o of the absolute coordinate system, the positive direction of the horizontal axis y is directly in front, and the positive direction of the vertical axis z is directly above. At the same time, in order to facilitate calculation, an AM point is set on the excavator working device for identification and coordinate point calculation. A represents the hinge point of the rear support of the boom, B represents the hinge point of the large cavity of the boom cylinder, B1 represents the negative translation point of the horizontal axis of point B, which does not represent the specific position and is only used for direction. C represents the middle support of the boom, that is, the hinge point of the small cavity of the boom cylinder, D represents the hinge point of the large cavity of the bucket cylinder, E represents the front support of the boom, that is, the hinge point of the rear support of the bucket, F represents the hinge point of the small cavity of the bucket cylinder, G represents the hinge point of the large cavity of the bucket cylinder, J represents the hinge point of the small cavity of the bucket cylinder, H represents the hinge point of the middle support of the bucket, K represents the hinge point of the front support of the bucket, that is, the hinge point of the rear ear plate of the bucket, L represents the hinge point of the front ear plate of the bucket, and M represents the tip of the bucket tooth;

[0107] Boom posture:

[0108] BC length is calculated from the smallest to the largest size of the boom cylinder, with a 1mm interval.

[0109] a=acos((AB^2+AC^2-BC^2) / (2*AB*AC))-∠EAC-∠ABB1;

[0110] Determine when a+∠EAC+∠ABB1 =π / 2;

[0111] Extract the current BC length;

[0112] Where: π represents pi, AB represents the distance between point A and point B, AC represents the distance between point A and point C, BC represents the length of the boom cylinder, that is, the distance between point B and point C, ∠EAC represents the angle formed by point E, point A, and point C, ∠ABB1 represents the angle formed by point A, point B, and point B1, and a represents the displacement angle of the boom relative to the platform;

[0113] Bucket posture:

[0114] GJ length is calculated from the smallest to the largest size of the bucket cylinder, with an interval of 1mm.

[0115] ∠GHJ=acos((GH^2+HJ^2-GJ^2) / (2*GH*HJ));

[0116] ∠JGH=acos((GH^2+GJ^2-HJ^2) / (2*GH*GJ));

[0117] ∠GJH=π-∠JGH-∠GHJ;

[0118] ∠JHK=∠GHK-∠GHJ;

[0119] JK=(HJ^2+HK^2-2*HJ*HK*cos(∠JHK))^0.5;

[0120] ∠JKL=acos((JK^2+KL^2-JL^2) / (2*JK*KL));

[0121] ∠JLK=acos((JL^2+KL^2-JK^2) / (2*JL*KL));

[0122] ∠JKH=acos((HK^2+JK^2-HJ^2) / (2*JK*HK));

[0123] ∠LJH=2π-∠JHK-∠JKH-∠JKL-∠JLK;

[0124] Fbucket=(pc*sc)*10^6;

[0125] Fwbucket=((Fbucket*sin(∠GJH) / sin(∠LJH))*sin(∠JLK)*KL) / (KM);

[0126] Where: GJ represents the length of the bucket cylinder, that is, the distance between points G and J; ∠GHJ represents the angle formed by points G, H, and J; GH represents the distance between points G and H; HJ represents the distance between points H and J; ∠JGH represents the angle formed by points J, G, and H; ∠GJH represents the angle formed by points G, J, and H; ∠GHK represents the angle formed by points G, H, and K; ∠JHK represents the angle formed by points J, H, and K; JK represents the distance between points J and K; HK represents the distance between points H and K; ∠JKL represents the angle formed by points J, K, and L. The angle formed by KL is the distance between K and L, JL is the distance between J and L, ∠JLK is the angle formed by J, L and K, ∠JKH is the angle formed by J, K and H, ∠LJH is the angle formed by L, J and H, Fbucket is the bucket cylinder force, pc is the pressure of the bucket cylinder large chamber; sc is the area of ​​the bucket cylinder large chamber; KM is the distance between K and M, Fwbucket is the bucket digging force, find the maximum bucket digging force in the cycle, and extract the maximum bucket digging force posture GJ length;

[0127] Stick posture:

[0128] After determining GJ, calculate the maximum digging force of the bucket arm.

[0129] DF length is calculated from the smallest to the largest size of the boom cylinder, with an interval of 1mm.

[0130] ∠EFD=acos((DF^2+EF^2-ED^2) / (2*DF*EF));

[0131] Farm = (pa*sa)*10^6;

[0132] EM=(EK^2+KM^2-2*EK*KM*cos(π-c))^0.5;

[0133] Fwarm=(Farm*sin(∠EFD)*EF) / (EM);

[0134] Where: DF is the length of the boom cylinder, that is, the distance between point D and point F; ∠EFD is the angle formed by point E, point F, and point D; EF is the distance between point E and point F; ED is the distance between point E and point D; Farm is the boom cylinder force; pa is the pressure of the large cavity of the boom cylinder; sa is the area of ​​the large cavity of the boom cylinder; EM is the distance between point E and point M; Fwarm is the digging force of the boom; find the maximum digging force of the boom in the cycle, extract the DF length of the posture with the maximum digging force of the boom,

[0135] In summary, the instrument controller automatically calculates the lengths of the three cylinders under the maximum digging force posture.

[0136] Furthermore, the vehicle controller calculates the displacement angle a of the boom relative to the platform through the maximum digging force cylinder length program:

[0137] a=acos((AB^2+AC^2-BC^2) / (2*AB*AC))-∠EAC-∠ABB1;

[0138] The displacement angle b of the bucket arm relative to the boom is calculated:

[0139] b=-(π-(2*π-∠AED-∠FEK-acos((ED^2+EF^2-DF^2) / (2*DE*EF))));

[0140] Where: ∠AED represents the angle formed by points A, E, and D; ∠FEK represents the angle formed by points F, E, and K;

[0141] The displacement angle c of the bucket relative to the dipper arm is calculated:

[0142] ∠GHJ=acos((GH^2+HJ^2-GJ^2) / (2*GH*HJ));

[0143] ∠JGH=acos((GH^2+GJ^2-HJ^2) / (2*GH*GJ));

[0144] ∠GJH=π-∠JGH-∠GHJ;

[0145] ∠JHK=∠GHK-∠GHJ;

[0146] JK=(HJ^2+HK^2-2*HJ*HK*cos(∠JHK))^0.5;

[0147] ∠JKL=acos((JK^2+KL^2-JL^2) / (2*JK*KL));

[0148] ∠JKH=acos((HK^2+JK^2-HJ^2) / (2*JK*HK));

[0149] c=-(π-(2*π-∠EKH-∠JKL-∠MKL-∠JKH));

[0150] The specific steps for calculating the height and angle that the pull rope should be adjusted are as follows:

[0151] Calculate the coordinate position of the front support of the boom, that is, the hinge point E of the rear support of the bucket arm:

[0152] Ye = AE * cos (a);

[0153] Ze = AE*sin(a);

[0154] Where: Ye represents the position of point E on the horizontal axis, Ze represents the position of point E on the vertical axis; AE represents the distance between point A and point E;

[0155] Calculate the coordinate position of point M at the bucket tooth tip:

[0156] Ym=EK*cos(a+b)+AE*cos(a)+KM*cos(a+b+c);

[0157] Zm=EK*sin(a+b)+AE*sin(a)+KM*sin(a+b+c);

[0158] In the formula, Ym represents the position of point M on the horizontal axis, and Zm represents the position of point M on the vertical axis;

[0159] Therefore, the fixing point of the pull rope on the ground anchor can be calculated;

[0160] The fixing point P2 of the digging force rope of the bucket arm on the ground anchor:

[0161] EM=((Ym-Ye)^2+(Zm-Ze)^2)^0.5;

[0162] ∠EMK=acos((EM^2+KM^2-EK^2) / (2*EM*KM));

[0163] P2=MN2*sin(ab-c+π / 2+∠EMK)+Zm+L1;

[0164] Where, P2 represents the distance from the fixed point of the digging force rope of the bucket arm to the bottom of the pit, ∠EMK represents the angle formed by points E, M, and K, L1 represents the platform height, and MN2 represents the length of the rope under the digging force posture of the bucket arm;

[0165] Bucket digging force rope fixed point P1 on the ground anchor:

[0166] P1=L1-MN1*sin(b+c-a+π / 2)+Zm;

[0167] Where P1 represents the distance from the fixed point of the bucket digging force rope to the bottom of the pit, and MN1 represents the length of the rope in the bucket digging force posture.

[0168] like Figure 3 As shown, the specific operation process of this embodiment is as follows:

[0169] S0: Start, determine the test posture.

[0170] S1: When the maximum digging force posture is selected, the instrument controller automatically obtains the lengths of the boom cylinder, the arm cylinder, and the bucket cylinder.

[0171] S2: If the normal posture is selected, the instrument controller needs to manually input the lengths of the three cylinders: the boom cylinder, the arm cylinder, and the bucket cylinder, and send the data to the vehicle controller.

[0172] S3: The instrument controller sends an “automatic test start” command to the vehicle controller.

[0173] S4: The vehicle controller automatically calculates the movement angle a of the boom relative to the slewing platform, the movement angle b of the arm relative to the boom, and the movement angle c of the bucket relative to the arm.

[0174] S5: The vehicle controller calculates the height and angle parameters that the pull rope should be adjusted to, and the pull rope is automatically adjusted to the specified position.

[0175] S6: Bucket cylinder slowly loads.

[0176] S7: Determine whether the main pump overflows, if so, proceed to "S8", if not, return to "S6".

[0177] S8: The sensor feeds the test data back to the vehicle controller, and the vehicle controller sends the data back to the instrument controller.

[0178] S9: The instrument controller determines whether the data is qualified. If qualified, it enters "S10". If not, it returns to "S2" and manually inputs the lengths of the three cylinders: the boom cylinder, the dipper cylinder, and the bucket cylinder.

[0179] S10: The instrument controller records qualified bucket digging force data.

[0180] S11: The boom cylinder is loaded slowly.

[0181] S12: Determine whether the main pump overflows, if so, proceed to "S13", if not, return to "S11".

[0182] S13: The sensor feeds back the test data to the vehicle controller, and the vehicle controller sends the data back to the instrument controller.

[0183] S14: The instrument controller determines whether the data is qualified. If qualified, it enters "S15". If not, it returns to "S2" and manually inputs the lengths of the three cylinders: the boom cylinder, the dipper cylinder, and the bucket cylinder.

[0184] S15: The instrument controller records qualified bucket digging force data.

[0185] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. An automatic digging force testing system for an excavator, characterized in that: include: The instrument controller is used to obtain the working device parameters of the excavator, judge the test posture of the excavator according to the working device parameters, obtain the three cylinder length information of the boom cylinder, the dipper arm cylinder and the bucket cylinder after judging the test posture of the excavator, and send the automatic test start instruction and the three cylinder length information to the vehicle controller at the same time; receive the test data sent by the vehicle controller and make a judgment, and record the bucket digging force and dipper arm digging force data after judging that it is qualified; if it is unqualified, continue to send the three cylinder length information to the vehicle controller until the test data recording is qualified; After the vehicle controller receives the three cylinder length information and automatic test instructions sent by the instrument controller, the automatic digging force test program starts to work. The maximum digging force cylinder length program calculates the arm's relative movement angle a to the slewing platform, the arm's relative movement angle b, the bucket's relative movement angle c, and the height and angle that the pull rope should be adjusted. The pull rope is automatically adjusted to the specified position. At the same time, the test data sent by the sensor is fed back to the instrument controller. The sensor is used to collect test data when the main pump overflows during the slow loading process of the bucket cylinder and the dipper cylinder, and send the test data to the vehicle controller; The excavator test posture includes a maximum digging force test posture and a normal test posture; if the excavator test posture is the maximum digging force posture, the instrument controller automatically calculates the three cylinder lengths of the boom cylinder, the dipper arm cylinder, and the bucket cylinder in the maximum digging force posture; if the test posture is the normal posture or the instrument controller determines that the test data is unqualified, the three cylinder lengths of the boom cylinder, the dipper arm cylinder, and the bucket cylinder need to be manually input; The test data includes pressure, displacement and tension data of the boom cylinder, the dipper cylinder and the bucket cylinder; The sensors include a wire displacement sensor installed on the boom cylinder, the dipper cylinder and the bucket cylinder, a pressure sensor, and a dynamometer sensor installed between the ground anchor and the bucket; When the model and size of the working device of the excavator are known, a two-dimensional coordinate system is established with the intersection of the rotation center and the horizontal line as the origin o of the absolute coordinate system, the positive direction of the horizontal axis y is directly in front, and the positive direction of the vertical axis z is directly above. Points A, E, K, and M are set on the working device of the excavator for identification and coordinate point calculation. A represents the hinge point of the rear support of the boom, E represents the hinge point of the front support of the boom, i.e. the rear support of the bucket arm, K represents the hinge point of the front support of the bucket arm, i.e. the rear ear plate of the bucket, and M represents the tip of the bucket tooth. The specific steps for calculating the height and angle that the pull rope should be adjusted are as follows: Calculate the coordinate position of the front support of the boom, that is, the hinge point E of the rear support of the bucket arm: Ye = AE*cos(a); Ze = AE*sin(a); Where: Ye represents the position of point E on the horizontal axis, Ze represents the position of point E on the vertical axis; AE represents the distance between point A and point E; Calculate the coordinate position of point M at the bucket tooth tip: Ym=EK*cos(a+b)+AE*cos(a)+KM*cos(a+b+c); Zm=EK*sin(a+b)+AE*sin(a)+KM*sin(a+b+c); In the formula, Ym represents the position of point M on the horizontal axis, and Zm represents the position of point M on the vertical axis; Therefore, the fixing point of the pull rope on the ground anchor can be calculated; The fixing point P2 of the digging force rope of the bucket arm on the ground anchor: EM=((Ym-Ye)^2+(Zm-Ze)^2)^0.5; ∠EMK=acos((EM^2+KM^2-EK^2) / (2*EM*KM)); P2=MN2*sin(ab-c+π / 2+∠EMK)+Zm+L1; Where, P2 represents the distance from the fixed point of the digging force rope of the bucket arm to the bottom of the pit, ∠EMK represents the angle formed by points E, M and K, L1 represents the platform height, and MN2 represents the length of the rope in the digging force posture of the bucket arm; Bucket digging force rope fixed point P1 on the ground anchor: P1=L1-MN1*sin(b+c-a+π / 2)+Zm; Where P1 represents the distance from the fixed point of the bucket digging force rope to the bottom of the pit, and MN1 represents the length of the rope in the bucket digging force posture.

2. A method for using the automatic digging force testing system for an excavator according to claim 1, characterized in that: The following steps are involved: (1) Determine the test posture through the instrument controller, obtain the lengths of the three cylinders: the boom cylinder, the arm cylinder, and the bucket cylinder, and send the data to the vehicle controller; (2) The vehicle controller automatically calculates the angle a of the boom relative to the slewing platform, the angle b of the arm relative to the boom, the angle c of the bucket relative to the arm, and the height and angle of the pull rope to be adjusted, and the pull rope is automatically adjusted to the specified position; (3) During the slow loading of the bucket cylinder and the boom cylinder, after the main pump overflows, the sensor feeds back the test data to the vehicle controller, and the vehicle controller transmits the test data to the instrument controller; (4) The instrument controller makes a judgment and records the bucket digging force and dipper arm digging force data if they are qualified; if they are unqualified, the lengths of the boom cylinder, dipper arm cylinder, and bucket cylinder are sent to the vehicle controller, and the process of (2), (3), and (4) is repeated until the data are judged to be qualified and the recording is completed.

3. The automatic digging force testing method for an excavator according to claim 2, characterized in that: The length information of the three cylinders is obtained by selecting one of the following methods according to the excavator test posture: (1) If the excavator test posture is the maximum digging force posture, the instrument controller automatically calculates the lengths of the three cylinders under the maximum digging force posture; (2) If the test posture is normal or the instrument controller determines that the test data is unqualified, you need to manually enter the three cylinder lengths.

4. The automatic digging force testing method for an excavator according to claim 3, characterized in that: The steps to automatically calculate the lengths of the three cylinders at the maximum digging force posture through the instrument controller are as follows: B, B1, C, D, F, G, J, H, and L points are set on the excavator working device for identification and coordinate point calculation. B represents the large cavity hinge point of the boom cylinder. B1 represents the horizontal axis negative translation point of point B, which does not represent the specific position and is only used for direction. C represents the middle support of the boom, that is, the small cavity hinge point of the boom cylinder. D represents the large cavity hinge point of the arm cylinder. F represents the small cavity hinge point of the arm cylinder. G represents the large cavity hinge point of the bucket cylinder. J represents the small cavity hinge point of the bucket cylinder. H represents the hinge point of the middle support of the arm. L represents the hinge point of the front ear plate of the bucket. Boom posture: BC length is calculated from the smallest to the largest size of the boom cylinder, with a 1mm interval. a=acos((AB^2+AC^2-BC^2) / (2*AB*AC))-∠EAC-∠ABB1; Determine when a+∠EAC+∠ABB1 =π / 2; Extract the current BC length; Where: π represents pi, AB represents the distance between point A and point B, AC represents the distance between point A and point C, BC represents the length of the boom cylinder, that is, the distance between point B and point C, ∠EAC represents the angle formed by point E, point A, and point C, ∠ABB1 represents the angle formed by point A, point B, and point B1, and a represents the displacement angle of the boom relative to the platform; Bucket posture: GJ length is calculated from the smallest to the largest size of the bucket cylinder, with an interval of 1mm. ∠GHJ=acos((GH^2+HJ^2-GJ^2) / (2*GH*HJ)); ∠JGH=acos((GH^2+GJ^2-HJ^2) / (2*GH*GJ)); ∠GJH=π-∠JGH-∠GHJ; ∠JHK=∠GHK-∠GHJ; JK=(HJ^2+HK^2-2*HJ*HK*cos(∠JHK))^0.5; ∠JKL=acos((JK^2+KL^2-JL^2) / (2*JK*KL)); ∠JLK=acos((JL^2+KL^2-JK^2) / (2*JL*KL)); ∠JKH=acos((HK^2+JK^2-HJ^2) / (2*JK*HK)); ∠LJH=2π-∠JHK-∠JKH-∠JKL-∠JLK; Fbucket=(pc*sc)*10^6; Fwbucket=((Fbucket*sin(∠GJH) / sin(∠LJH))*sin(∠JLK)*KL) / (KM); Where: GJ represents the length of the bucket cylinder, that is, the distance between points G and J; ∠GHJ represents the angle formed by points G, H, and J; GH represents the distance between points G and H; HJ represents the distance between points H and J; ∠JGH represents the angle formed by points J, G, and H; ∠GJH represents the angle formed by points G, J, and H; ∠GHK represents the angle formed by points G, H, and K; ∠JHK represents the angle formed by points J, H, and K; JK represents the distance between points J and K; HK represents the distance between points H and K; ∠JKL represents the angle formed by points J, K, and L. The angle formed by KL is the distance between K and L, JL is the distance between J and L, ∠JLK is the angle formed by J, L and K, ∠JKH is the angle formed by J, K and H, ∠LJH is the angle formed by L, J and H, Fbucket is the bucket cylinder force, pc is the pressure of the bucket cylinder large chamber; sc is the area of ​​the bucket cylinder large chamber; KM is the distance between K and M, Fwbucket is the bucket digging force, find the maximum bucket digging force in the cycle, and extract the maximum bucket digging force posture GJ length; Stick posture: After determining GJ, calculate the maximum digging force of the bucket arm. DF length is calculated from the smallest to the largest size of the boom cylinder, with an interval of 1mm. ∠EFD=acos((DF^2+EF^2-ED^2) / (2*DF*EF)); Farm = (pa*sa)*10^6; EM=(EK^2+KM^2-2*EK*KM*cos(π-c))^0.5; Fwarm=(Farm*sin(∠EFD)*EF) / (EM); Where: DF represents the length of the boom cylinder, that is, the distance between point D and point F; ∠EFD represents the angle formed by points E, F, and D; EF represents the distance between points E and F; ED represents the distance between points E and D; Farm represents the boom cylinder force; pa represents the large chamber pressure of the boom cylinder; sa represents the large chamber area of ​​the boom cylinder; EM represents the distance between points E and M; Fwarm represents the boom digging force; find the maximum boom digging force in the cycle, and extract the DF length of the maximum boom digging force posture; In summary, the instrument controller automatically calculates the lengths of the three cylinders under the maximum digging force posture.

5. The automatic digging force testing method for an excavator according to claim 4, characterized in that: The vehicle controller calculates the displacement angle a of the boom relative to the platform through the maximum digging force cylinder length program: a=acos((AB^2+AC^2-BC^2) / (2*AB*AC))-∠EAC-∠ABB1; The displacement angle b of the bucket arm relative to the boom is calculated: b=-(π-(2*π-∠AED-∠FEK-acos((ED^2+EF^2-DF^2) / (2*DE*EF)))); Where: ∠AED represents the angle formed by points A, E, and D; ∠FEK represents the angle formed by points F, E, and K; The displacement angle c of the bucket relative to the dipper arm is calculated: ∠GHJ=acos((GH^2+HJ^2-GJ^2) / (2*GH*HJ)); ∠JGH=acos((GH^2+GJ^2-HJ^2) / (2*GH*GJ)); ∠GJH=π-∠JGH-∠GHJ; ∠JHK=∠GHK-∠GHJ; JK=(HJ^2+HK^2-2*HJ*HK*cos(∠JHK))^0.5; ∠JKL=acos((JK^2+KL^2-JL^2) / (2*JK*KL)); ∠JKH=acos((HK^2+JK^2-HJ^2) / (2*JK*HK)); c=-(π-(2*π-∠EKH-∠JKL-∠MKL-∠JKH)).

Images