A small backhoe excavator shovel resistance test platform

Abstract

The application discloses a small-sized backhoe excavator digging resistance test platform, which is applied to the technical field of engineering machinery and comprises a bucket, a mechanical arm device, a measuring device, a workbench and a control device. The bucket is hinged to the mechanical arm device, and the mechanical arm device is fixed to the workbench. The control device is electrically connected to the measuring device. A force balance equation is constructed by data collected by the measuring device, and digging resistance is obtained through stress analysis. The application provides a small-sized backhoe excavator digging resistance test platform, which has a small size, can simulate the digging process and measure the digging resistance in a laboratory indoor environment, and can effectively reduce the working strength of test personnel, improve the efficiency of scientific research, reduce the research and development cost, and simultaneously control the test platform simply, respond quickly, save the manufacturing cost, reduce the weight of the equipment and be more convenient to manufacture.

Description

Technical Field

[0001] This invention relates to the field of engineering machinery technology, and more specifically to a testing platform for the digging resistance of a small backhoe excavator. Background Technology

[0002] Currently, excavators are the most widely used and prevalent type of earthmoving machinery in the market. The bucket and bucket teeth are core components of excavators, directly interacting with the working medium and bearing significant impact loads. In extreme conditions such as clay, frozen soil, and gravel, problems like bucket cracking and bucket tooth breakage can occur, severely impacting excavator operating efficiency. Currently, excavators lack direct resistance testing devices, making it difficult for operators to accurately assess digging resistance. This often leads to overloading when excavating or breaking large rocks, resulting in severe bucket wear.

[0003] Due to the complex operating conditions of excavators and the constantly changing forces on the bucket, the digging resistance cannot be directly measured by installing sensors on the bucket, making the acquisition of digging resistance a technical challenge.

[0004] Existing methods for testing digging resistance mostly involve installing pressure and displacement sensors at the hydraulic cylinder and pin sensors at each hinge point. The sensor values ​​are measured during digging operations, and the bucket digging resistance value is calculated through theoretical derivation. However, existing testing technologies have two main drawbacks: first, the sensor installation and acquisition system is complex, and the pin sensors need to be customized, resulting in long lead times and high costs; second, the testing accuracy is low, the bucket resistance calculation formula is complex, and the derived calculation results cannot accurately and intuitively reflect the resistance experienced during bucket digging operations.

[0005] Therefore, how to provide an easy-to-operate and simple-to-calculate testing platform for the digging resistance of small backhoe excavators is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0006] In view of this, the present invention provides a small backhoe excavator digging resistance testing platform to solve the problems of complex calculations and difficult sensor deployment in the prior art.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A small backhoe excavator digging resistance testing platform includes: a bucket, a robotic arm device, a measuring device, a workbench, and a control device;

[0009] The bucket is hinged to the robotic arm, which is fixed to the workbench. The control device is electrically connected to the measuring device. The force balance equation is constructed using the data collected by the measuring device, and the digging resistance is obtained through force analysis.

[0010] Preferably, in the above-mentioned small backhoe excavator digging resistance test platform, the robotic arm device includes: a forearm, a bucket electric push rod, a boom, a forearm electric push rod, a boom electric push rod, a bucket connecting rod, and a forearm connecting rod;

[0011] The boom and the forearm are hinged together; the fixed end of the bucket electric push rod is fixed to the forearm, and the free end is hinged to the bucket through the bucket connecting rod, driving the bucket to move; one end of the forearm connecting rod is hinged to the forearm, and the other end is connected to the hinge point of the bucket electric push rod through the bucket connecting rod; the fixed end of the forearm electric push rod is fixed to the boom, and the free end is connected to the forearm, driving the forearm to move; the fixed end of the boom electric push rod is fixed to the workbench, and the free end is connected to the boom, driving the boom to move.

[0012] Preferably, in the above-mentioned small backhoe excavator digging resistance testing platform, the measuring device includes: a bucket push rod displacement sensor, a boom push rod displacement sensor, a boom push rod displacement sensor, and four pin sensors; the bucket push rod displacement sensor is installed on the bucket electric push rod to obtain the displacement of the bucket electric push rod; the boom push rod displacement sensor is installed on the boom electric push rod to obtain the displacement of the boom electric push rod; the boom push rod displacement sensor is installed on the boom electric push rod to obtain the displacement of the boom electric push rod; the pin sensors are installed on both sides of the bucket-boom hinge point and on both sides of the bucket connecting rod-bucket hinge point.

[0013] Preferably, in the above-mentioned small backhoe excavator digging resistance testing platform, the control device includes: a drive unit, a data acquisition card, a host computer, a displacement sensor signal processing module, and a pin shaft sensor signal processing module; the drive unit drives the bucket electric push rod, the boom electric push rod, and the boom electric push rod respectively; the displacement signal processing module is electrically connected to the bucket push rod displacement sensor, the boom push rod displacement sensor, and the boom push rod displacement sensor respectively; the pin shaft sensor signal processing module is electrically connected to the four pin shaft sensors respectively; the drive unit, the displacement sensor signal processing module, and the pin shaft sensor signal processing module are electrically connected to the data acquisition card respectively; the data acquisition card interacts with the host computer.

[0014] Preferably, in the above-mentioned small backhoe excavator digging resistance testing platform, the robotic arm device includes: a forearm, a bucket electric push rod, a boom, a forearm electric push rod, a boom electric push rod, a bucket connecting rod, a forearm connecting rod, a sensor bracket, and a boom articulation frame;

[0015] The big arm is hinged with the small arm; the fixed end of the bucket electric push rod is fixed on the small arm, and the free end is hinged with the bucket through the bucket connecting rod to drive the bucket to act; one end of the small arm connecting rod is hinged with the small arm, and the other end is connected with the hinge point of the bucket electric push rod through the bucket connecting rod; the fixed end of the small arm electric push rod is fixed on the big arm, and the free end is connected with the small arm to drive the small arm to act; the fixed end of the big arm electric push rod is fixed on the movable arm hinge frame, and the free end is connected with the big arm to drive the big arm to act; the movable arm hinge frame is installed on the working frame through the sensor support.

[0016] Preferably, in the above-mentioned small backhoe excavator digging resistance test platform, the measuring device comprises six force sensors; the sensor support is composed of mutually perpendicular first and second mounting surfaces; the first and second mounting surfaces are respectively provided with three force sensors, and the three force sensors on each mounting surface are arranged in a triangular shape; the first component of resistance is obtained according to the first mounting surface, and the second component of resistance is obtained through the second mounting surface; and the left and right offset distances and the roll offset distance are obtained according to the differences of the force sensors on each mounting surface.

[0017] Preferably, in the above-mentioned small backhoe excavator digging resistance test platform, the control device comprises a driving device, a force sensor transmitter group, a data acquisition card and an upper computer; the driving device drives the bucket electric push rod, the small arm electric push rod and the big arm electric push rod respectively; the force sensor transmitter group is electrically connected with the six force sensors respectively; the driving device and the force sensor transmitter group are electrically connected with the data acquisition card respectively; and the data acquisition card and the upper computer interact with each other.

[0018] According to the above technical solution, compared with the prior art, the present application provides a small backhoe excavator digging resistance test platform, which has a small volume, can simulate the digging process and measure the digging resistance in a laboratory indoor environment, can effectively reduce the working intensity of test personnel, improve the efficiency of scientific research work, reduce the research and development cost, has simple control, fast response speed, saves manufacturing cost, reduces the weight of the equipment, and is more convenient to manufacture. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of the provided drawings.

[0020] Figure 1 is a whole side view of embodiment 1 of the present application;

[0021] Figure 2 is a whole front view of embodiment 1 of the present application;

[0022] Figure 3 is an electrical connection schematic diagram of embodiment 1 of the present application;

[0023] Figure 4 is a pin shaft sensor installation position schematic diagram of embodiment 1 of the present application;

[0024] Figure 5 is a force diagram of the bucket of embodiment 1 of the present application;

[0025] Figure 6 is a pin shaft sensor schematic diagram of embodiment 1 of the present application;

[0026] Figure 7 is a whole side view of embodiment 2 of the present application;

[0027] Figure 8 is a force sensor installation position schematic diagram of embodiment 2 of the present application;

[0028] Figure 9 is an electrical connection schematic diagram of embodiment 2 of the present application;

[0029] Figure 10 is a resistance position schematic diagram of embodiment 2 of the present application;

[0030] Figure 11 is a sensor group force diagram of embodiment 2 of the present application;

[0031] Figure 12 is a deflection distance force diagram of embodiment 2 of the present application. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0033] Embodiment 1

[0034] The present embodiment discloses a small-sized backhoe excavator digging resistance test platform, comprising: a bucket, a mechanical arm device, a measuring device, a workbench and a control device.

[0035] The shovel is hinged to the mechanical arm device, the mechanical arm device is fixed on the workbench, the control device is electrically connected with the measuring device, the force balance equation is constructed by the data collected by the measuring device, and the shovel digging resistance is obtained through stress analysis.

[0036] In order to further optimize the above technical scheme, the mechanical arm device comprises: a small arm, a shovel electric push rod, a large arm, a small arm electric push rod, a large arm electric push rod, a shovel connecting rod and a small arm connecting rod.

[0037] The large arm is hinged to the small arm, the fixed end of the shovel electric push rod is fixed on the small arm, the free end is hinged to the shovel through the shovel connecting rod, and the shovel is driven to move; one end of the small arm connecting rod is hinged to the small arm, and the other end is connected to the hinge point of the shovel electric push rod through the shovel connecting rod; the fixed end of the small arm electric push rod is fixed on the large arm, and the free end is connected with the small arm to drive the small arm to move; the fixed end of the large arm electric push rod is fixed on the workbench, and the free end is connected with the large arm to drive the large arm to move.

[0038] In order to further optimize the above technical scheme, the measuring device comprises: a shovel push rod displacement sensor, a small arm push rod displacement sensor, a large arm push rod displacement sensor and four pin shaft sensors; the shovel push rod displacement sensor is installed on the shovel electric push rod to obtain the displacement of the shovel electric push rod; the small arm push rod displacement sensor is installed on the small arm electric push rod to obtain the displacement of the small arm electric push rod; the large arm push rod displacement sensor is installed on the large arm electric push rod to obtain the displacement of the large arm electric push rod; the pin shaft sensor is installed on both sides of the hinge point of the shovel and the small arm, and on both sides of the hinge point of the shovel connecting rod and the shovel.

[0039] In order to further optimize the above technical scheme, the control device comprises: a driving device, a data acquisition card, an upper computer, a displacement sensor signal processing module and a pin shaft sensor signal processing module; the driving device drives the shovel electric push rod, the small arm electric push rod and the large arm electric push rod respectively; the displacement sensor signal processing module is electrically connected with the shovel push rod displacement sensor, the small arm push rod displacement sensor and the large arm push rod displacement sensor respectively; the pin shaft sensor signal processing module is electrically connected with the four pin shaft sensors respectively; the driving device, the displacement sensor signal processing module and the pin shaft sensor signal processing module are electrically connected with the data acquisition card respectively; the data acquisition card and the upper computer interact with each other.

[0040] Specifically, the mechanical working part comprises a material box fixing frame 1, a material box 2, a shovel 3, a small arm 4, a shovel electric push rod 5, a large arm 7, a small arm electric push rod 8, a large arm electric push rod 10, a workbench 12, a counterweight 14, a shovel connecting rod 16, a small arm connecting rod 17;

[0041] The sensing and detection section includes a bucket push rod displacement sensor 6, a boom push rod displacement sensor 9, a boom push rod displacement sensor 11, and a pin sensor 15.

[0042] The control unit includes an electrical cabinet 13, a bucket push rod drive module 13.1, a boom push rod drive module 13.2, a boom push rod drive module 13.3, a data acquisition card 13.4, a computer 13.5, a displacement sensor signal processing module 13.6, and a pin shaft sensor signal processing module 13.7.

[0043] The pin sensors 15 include a left bucket boom pin sensor 15.2 and a right bucket boom pin sensor 15.3 installed between the bucket 3 and the boom 4, and a left bucket stick pin sensor 15.1 and a right bucket stick pin sensor 15.4 installed between the bucket 3 and the bucket connecting rod 16. All pin sensors 15 are fixed to the bucket 3. Figure 4 As shown.

[0044] Among them, the bucket electric push rod 5, the boom electric push rod 8, the boom electric push rod 10, the bucket push rod drive module 13.1, the boom push rod drive module 13.2, the boom push rod drive module 13.3, the data acquisition card 13.4, and the computer 13.5 together constitute the posture control system, which controls the test platform to complete the specified actions.

[0045] The data acquisition card 13.4, computer 13.5, displacement sensor signal processing module 13.6, bucket push rod displacement sensor 6, boom push rod displacement sensor 9, and boom push rod displacement sensor 11 together constitute a posture monitoring system, which is responsible for monitoring the real-time position and posture information of the test platform.

[0046] The pin sensor 15, data acquisition card 13.4, computer 13.5, and pin sensor signal processing module 13.7 together constitute a resistance measurement system, which is responsible for measuring the digging resistance experienced by the bucket during operation.

[0047] The material box fixing frame 1 is used to position the material box to ensure that the material box does not undergo relative displacement with the test platform during the operation of the test platform, thus affecting the experimental results.

[0048] The counterweight 14 is used to adjust the center of gravity of the test platform to ensure that it does not tip over during operation.

[0049] Specifically, the digging resistance experienced by the bucket during operation is obtained using a four-pin sensor system. The specific calculation process involves considering the digging resistance F, the bucket's own weight G, and the reaction forces F1 and F2 from the two pins during operation. Figure 5As shown. The direction of the line connecting the centers of the two pin holes on the same side of the bucket is defined as the x-direction, and the y-direction is perpendicular to the x-direction. Since the force on the bucket along the pin axis usually comes from the pressure of the material on both sides of the bucket, and these pressures can largely cancel each other out, resulting in a smaller total force on the bucket in this direction, the force on the bucket along the pin axis is not considered here. According to the principle of force balance, the force balance equation for bucket 3 is:

[0050]

[0051] In the formula F 1x F represents the total force in the x-direction acting on the pin at point K. 1y F represents the total force in the y-direction acting on the pin at point K. 2x F represents the total force in the x-direction acting on the pin at point Q. 2y G represents the total force in the y-direction acting on the pin at point Q; x The x-component of the weight G of the bucket 3; G y The y-axis component of the weight G of the bucket 3; F x F is the x-axis component of the digging resistance; y Let be the component of the digging resistance in the y-direction. From this, the magnitude F and direction α of the real-time digging resistance experienced by bucket 3 can be calculated as follows:

[0052]

[0053]

[0054] The angle α3 between the self-weight G of the bucket 3 and the x-direction can be calculated using the real-time position and attitude of the bucket. Specifically, the bucket push rod displacement sensor 6, the boom push rod displacement sensor 9, and the boom push rod displacement sensor 11 transmit the length information l1, l2, and l3 of the bucket electric push rod 5, the boom electric push rod 8, and the boom electric push rod 10 in real time through the displacement sensor signal processing module 13.6, and then to the computer 13.5 via the data acquisition card 13.4. The computer 13.5 calculates α3 using the following mathematical method:

[0055]

[0056] in:

[0057]

[0058] In the above formula, l KQ l MK l QN l MN l AF l FB l AC l FA l EF l FBAnd ∠CAS, ∠DFB, ∠EFQ, ∠NQF, ∠GNQ are fixed geometric dimensions and angles of the experimental platform working device, and the labels are as shown in Figure 2 .

[0059] Wherein K is the total force F 1x x direction of the pin shaft, which is obtained by the left bucket arm pin sensor 15.1 and the right bucket arm pin sensor 15.4 jointly measuring, and the specific process is that the inner hole of the left bucket arm pin sensor 15.1 is attached with strain gauges R x1 , R x2 , R x3 , R x4 on the x direction longitudinal section, R x1 and R x4 are located on the left bucket arm pin sensor 15.1 transverse section A-A, and R x2 and R x3 are located on the left bucket arm pin sensor 15.1 transverse section B-B, the horizontal distance between transverse section A-A and transverse section B-B is L, the distance between the x direction force F 1xl of the left bucket arm pin sensor 15.1 and transverse section B-B is l, the initial parameters of the four strain gauges are equal, and they are connected in full bridge mode, and the strain gauge installation mode is as shown in Figure 6 (a)-(b). According to the principle of Wheatstone bridge, the x direction force F 1xl of the left bucket arm pin sensor 15.1 can be obtained:

[0060]

[0061] In the above formula, E is the elastic modulus of the pin shaft material; W p is the bending section modulus of the pin shaft material; K0 is the sensitivity coefficient of the strain gauge; U 1xl0 is the input voltage of the x direction bridge of the left bucket arm pin sensor 15.1; U 1xli is the output voltage of the x direction bridge of the left bucket arm pin sensor 15.1.

[0062] During operation, the output voltage change of the x direction strain gauge of the left bucket arm pin sensor 15.1 will be processed by the pin sensor signal processing module 13.7, transmitted to the computer 13.5 through the data acquisition card 13.4, and the computer 13.5 calculates the real-time force F 1xl of the x direction of the left bucket arm pin sensor 15.1 according to the above formula.

[0063] The right bucket arm pin sensor 15.4 adopts the same strain gauge layout as the left bucket arm pin sensor 15.1, and the real-time force F 1xr of the x direction of the right bucket arm pin sensor 15.4 can be obtained as:

[0064]

[0065] wherein U 1xr0 is the x-direction bridge input voltage to the right bucket arm pin sensor 15.4; U 1xri is the x-direction bridge output voltage of the right bucket arm pin sensor 15.4.

[0066] The total x-direction force Fx at K experienced by the pin can be calculated from the above equation as: 1x

[0067]

[0068] The total y-direction force Fy at K experienced by the pin can be calculated from the above equation as: 1y The measurements are obtained from the left bucket arm pin sensor 15.1 and the right bucket arm pin sensor 15.4, in particular, the inner hole of the left bucket arm pin sensor 15.1 is attached with strain gauges R y1 , R y2 , R y3 , R y4 , R y1 and R y4 are located on the cross section C-C of the left bucket arm pin sensor 15.1, and R y2 and R y3 are located on the cross section D-D of the left bucket arm pin sensor 15.1, the horizontal distance between the cross section C-C and the cross section D-D is the same as the horizontal distance between the cross section A-A and the cross section B-B, which is L, the same measurement and calculation method as F 1xl is used to calculate the real-time y-direction force F 1yl of the left bucket arm pin sensor 15.1 and the real-time y-direction force F 1yr of the right bucket arm pin sensor 15.4, then the y-direction force F 1yl of the bucket 3 and the bucket connecting rod 16 at the hinge is obtained by adding F 1yr and F 1y :

[0069]

[0070] wherein U 1yl0 is the y-direction bridge input voltage to the left bucket arm pin sensor 15.1; U 1yli is the y-direction bridge output voltage of the left bucket arm pin sensor 15.1; U 1yr0 is the y-direction bridge input voltage to the right bucket arm pin sensor 15.4; U 1yri is the y-direction bridge output voltage of the right bucket arm pin sensor 15.4.

[0071] ​Where F is the total force in the x direction on the pin at Q 2x and F is the total force in the y direction on the pin at Q 2y The same measurement and calculation method is used to obtain the real-time forces F 1x and F 1y : 2x and F 2y :

[0072]

[0073]

[0074] Where U 2xl0 is the input voltage of the x direction bridge of the left bucket arm pin sensor 15.2; U 2xli is the output voltage of the x direction bridge of the left bucket arm pin sensor 15.2; U 2xr0 is the input voltage of the x direction bridge of the right bucket arm pin sensor 15.3; U 2xri is the output voltage of the x direction bridge of the right bucket arm pin sensor 15.3; U 2yl0 is the input voltage of the y direction bridge of the left bucket arm pin sensor 15.2; U 2yli is the output voltage of the y direction bridge of the left bucket arm pin sensor 15.2; U 2yr0 is the input voltage of the y direction bridge of the right bucket arm pin sensor 15.3; U 2yri is the output voltage of the y direction bridge of the right bucket arm pin sensor 15.3.

[0075] After obtaining all the real-time information of the forces and angles, the real-time digging resistance F of the bucket can be calculated.

[0076] Embodiment 2

[0077] The embodiment discloses a small-sized backhoe excavator digging resistance test platform, comprising a bucket, a mechanical arm device, a measuring device, a workbench and a control device.

[0078] The bucket is hinged to the mechanical arm device, and the mechanical arm device is fixed to the workbench; the control device is electrically connected to the measuring device, and a force balance equation is constructed by data collected by the measuring device, and the digging resistance is obtained through stress analysis.

[0079] In order to further optimize the above technical scheme, the mechanical arm device comprises a small arm, a bucket electric push rod, a large arm, a small arm electric push rod, a large arm electric push rod, a bucket connecting rod, a small arm connecting rod, a sensor support and a boom hinge frame.

[0080] The big arm is hinged with the small arm; the fixed end of the bucket electric push rod is fixed on the small arm, and the free end is hinged with the bucket through the bucket connecting rod to drive the bucket to act; one end of the small arm connecting rod is hinged with the small arm, and the other end is connected with the hinge point of the bucket electric push rod through the bucket connecting rod; the fixed end of the small arm electric push rod is fixed on the big arm, and the free end is connected with the small arm to drive the small arm to act; the fixed end of the big arm electric push rod is fixed on the movable arm hinge frame, and the free end is connected with the big arm to drive the big arm to act; the movable arm hinge frame is installed on the working frame through the sensor support.

[0081] In order to further optimize the above technical scheme, the measuring device comprises six force sensors; the sensor support is composed of mutually perpendicular first and second mounting surfaces; the first and second mounting surfaces are respectively provided with three force sensors, and the three force sensors on each mounting surface are arranged in a triangular shape; the first component of resistance is obtained according to the first mounting surface, and the second component of resistance is obtained through the second mounting surface; and the left and right offset distances and the roll offset distance are obtained according to the differences of the force sensors on each mounting surface.

[0082] In order to further optimize the above technical scheme, the control device comprises a driving device, a force sensor transmitter group, a data acquisition card and an upper computer; the driving device respectively drives the bucket electric push rod, the small arm electric push rod and the big arm electric push rod; the force sensor transmitter group is respectively electrically connected with six force sensors; the driving device and the force sensor transmitter group are respectively electrically connected with the data acquisition card; and the data acquisition card and the upper computer interact with data.

[0083] The mechanical arm device comprises a bucket 3, a bucket connecting rod 16, a small arm connecting rod 17, a bucket electric push rod 5, a small arm 4, a small arm electric push rod 8, a big arm 7, a big arm electric push rod 10, a movable arm hinge frame 18, a force sensor module 19 and a working frame 12;

[0084] The measuring device comprises a force sensor module 19, which comprises a force sensor R119.1, a force sensor R219.2, a force sensor R319.3, a sensor support 19.4, a force sensor R419.5, a force sensor R519.6 and a force sensor R619.7;

[0085] The control device comprises an electrical cabinet 13, a driving module 13.8, a force sensor transmitter group 13.9, a data acquisition card 13.4 and a computer 13.5.

[0086] Among them, the bucket electric push rod 5, the boom electric push rod 8, the boom electric push rod 10, the drive module 13.8, the data acquisition card 13.4, and the computer 13.5 together constitute the motion control system of the robotic arm device, which controls the robotic arm device to complete the specified digging motion.

[0087] The force sensor module 19, force sensor transmitter group 13.9, data acquisition card 13.4, and computer 13.5 together constitute the digging resistance detection system, which is responsible for real-time measurement of the digging resistance encountered by the robotic arm device during its movement.

[0088] Specifically, two sets of one-dimensional force sensors arranged in a triangular pattern and installed perpendicularly to each other are used to measure the magnitude and direction of the digging resistance experienced by the bucket during operation, as well as the lateral and tilting deviations of the digging resistance. The specific calculation process is as follows: let the digging resistance experienced by the bucket 3 during operation be F, and let the component of the digging resistance parallel to the horizontal plane be F... x The component of the digging resistance perpendicular to the horizontal plane is F. y The angle between the digging resistance and the horizontal plane is α, and the horizontal distance a from the concentrated point of digging resistance to the x-axis measuring plane where the force measuring points of force sensors R119.1, R219.2, and R319.3 are located is α. x The vertical distance a from the concentrated point of digging resistance to the y-axis measuring plane where the force sensors R419.5, R519.6, and R619.7 are located is y. y ,like Figure 10 As shown. For F x and F y Vertical digging resistance component F z Since its effect on the digging resistance F is very small, it is not considered here.

[0089] For a sensor group consisting of force sensor R119.1, force sensor R219.2, and force sensor R319.3, the force situation is as follows: Figure 11 As shown in (a), the following force balance equations can be derived using the principle of force equilibrium:

[0090]

[0091] In the formula F 1x The force F measured by force sensor R119.1 23x Let M be the resultant force measured by force sensors R219.2 and R319.3, and let a1 be the vertical distance between the measuring points of force sensors R119.1 and R219.2. y To translate the shovel resistance to the x-axis measuring plane, its y-axis component F y The equivalent torque. From this equilibrium equation, the x-axis component of the digging resistance force F can be determined. xFor:

[0092] F x = F 1x + F 2x + F 3x ;

[0093] For the sensor group consisting of force sensor R4 19.5, force sensor R5 19.6, and force sensor R6 19.7, the force situation is as shown in Figure 11 (b). Using the principle of force balance, the following force balance equation can be listed:

[0094]

[0095] where F 45y is the resultant force measured by force sensor R4 19.5 and force sensor R5 19.6, F 6y is the force measured by force sensor R6 19.7, a2 is the horizontal distance between the force measurement points of force sensor R5 19.6 and force sensor R6 19.7, and M x is the equivalent moment of the x-direction component F x of the shovel digging resistance when it is translated to the y-direction measurement surface. From this balance equation, it can be known that the y-direction component F y of the shovel digging resistance is:

[0096] F y = F 4y + F 5y + F 6y ;

[0097] From this, the shovel digging resistance F can be obtained as:

[0098]

[0099] For the angle a between the shovel digging resistance and the horizontal plane, it can be calculated by the following formula:

[0100]

[0101] When the left-right offset distance of the shovel digging resistance occurs, the forces measured by force sensor R2 19.2 and force sensor R3 19.3 will be different, and the mechanical diagram is as shown in Figure 12 (a). Assuming that the horizontal distance between the force measurement points of force sensor R2 19.2 and force sensor R3 19.3 is a3, the balance equation at this point is:

[0102]

[0103] After arranging the above formula, the left-right offset distance b y of the shovel digging resistance can be obtained as:

[0104]

[0105] When the shovel resistance appears the side inclination deviation, the force measured by the force sensor R419.5 and the force sensor R519.6 will be different, and the mechanical diagram is shown as (b) in the figure. Figure 12 (b) shown. The horizontal distance between the force sensor R419.5 and the force sensor R519.6 is a4, and the balance equation at this point is:

[0106]

[0107] The above formula can be arranged to obtain the side inclination deviation b of the shovel resistance: x

[0108]

[0109] During the working process of the test bench, the force sensor R119.1, the force sensor R219.2, the force sensor R319.3, the force sensor R419.5, the force sensor R519.6 and the force sensor R619.7 will transmit the tension and pressure signals of the points where the sensors are located to the force sensor transducer group 13.9 in real time, and then transmit the signals to the computer 13.5 through the data acquisition card 13.4. The computer 13.5 will process the tension and pressure information of each sensor according to the above formula, and then obtain the real-time size and direction of the shovel resistance, and the left and right deviation and the side inclination deviation of the shovel resistance.

[0110] The embodiments in the specification are described in a progressive manner, and each embodiment focuses on the difference from other embodiments. The same and similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiments, the description is relatively simple because it corresponds to the method disclosed in the embodiments. The relevant parts can be referred to the description of the method.

[0111] The above description of the disclosed embodiments enables a person skilled in the art to implement or use the present application. Various modifications to the embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.​

Claims

1. A small-sized backhoe excavator shovel digging resistance test platform, characterized by, include: Bucket, robotic arm device, measuring device, workbench and control device; The bucket is hinged to the robotic arm, which is fixed to the workbench. The control device is electrically connected to the measuring device. The force balance equation is constructed using the data collected by the measuring device, and the digging resistance is obtained through force analysis. Specifically, the digging resistance experienced by the bucket during operation is obtained by using four pin-shaft sensors for joint measurement. The specific calculation process is as follows: The bucket experiences digging resistance during operation. F , Bucket weight G and the reaction force at the two pins F 1 and F 2 The function is to define the direction of the line connecting the centers of the two pin holes on the same side of the bucket as... x direction, y direction and x Since the force on the bucket along the pin axis is usually derived from the pressure of the material on both sides of the bucket, and these pressures largely cancel each other out, the total force on the bucket in this direction is relatively small. Therefore, the force on the bucket along the pin axis is not considered here. According to the principle of force balance, the force balance equation for the bucket is: ； wherein F 1x is K the force on the pin shaft in the direction of the total force; x the force on the pin shaft in the direction of the total force; F 1y is K the force on the pin shaft in the direction of the total force; y the force on the pin shaft in the direction of the total force; F 2x is Q the force on the pin shaft in the direction of the total force; x the force on the pin shaft in the direction of the total force; F 2y is Q the force on the pin shaft in the direction of the total force; y the force on the pin shaft in the direction of the total force; G x the force on the pin shaft in the direction of the total force; G the force on the pin shaft in the direction of the total force; x the force on the pin shaft in the direction of the total force; G y the force on the pin shaft in the direction of the total force; G the force on the pin shaft in the direction of the total force; y the force on the pin shaft in the direction of the total force; F x the force on the pin shaft in the direction of the total force; x the force on the pin shaft in the direction of the total force; F y the force on the pin shaft in the direction of the total force; y the force on the pin shaft in the direction of the total force; F the force on the pin shaft in the direction of the total force; α the force on the pin shaft in the direction of the total force; ； ； Wherein the self-weight of the bucket G With x The direction included angle α 3. The real-time position and posture of the bucket are calculated, and the specific process is as follows: The bucket push rod displacement sensor, the small arm push rod displacement sensor and the large arm push rod displacement sensor will real-time the length information of the bucket electric push rod, the small arm electric push rod and the large arm electric push rod l 1、 l 2、 l 3Through the processing of the displacement sensor signal processing module, the data acquisition card is transmitted to the computer, and the computer is calculated through the following mathematical method α 3 : ； in: ； In the above formula l KQ , l MK , l QN , l MN , l AF , l FB , l AC , l FA , l EF , l FB and ∠CAS , ∠DFB , ∠EFQ , ∠NQF , ∠ GNQ are the fixed geometry dimensions and angles of the experimental platform working device; wherein K the forces acting on the pin x directional total force F 1x is obtained by the left bucket arm pin sensor and the right bucket arm pin sensor, and the specific process is: The inner hole of the left bucket arm rod pin sensor is pasted with strain gauges on the longitudinal section x The longitudinal section is pasted with strain gauges R x1 , R x2 , R x3 , R x4 , R x1 The horizontal section A-A of the left bucket arm rod pin sensor is pasted with strain gauges R x4 The horizontal section B-B of the left bucket arm rod pin sensor is pasted with strain gauges, and the horizontal distance between the horizontal section A-A and the horizontal section B-B is R x2 The horizontal section B-B of the left bucket arm rod pin sensor is pasted with strain gauges, and the horizontal distance between the horizontal section A-A and the horizontal section B-B is R x3 The horizontal distance between the horizontal section A-A and the horizontal section B-B is L The horizontal distance between the horizontal section A-A and the horizontal section B-B is x The horizontal distance between the horizontal section A-A and the horizontal section B-B is F 1xl The horizontal distance between the horizontal section A-A and the horizontal section B-B is l The initial parameters of the four strain gauges are equal, and they are connected in full-bridge mode; according to the Wheatstone bridge principle, the horizontal force of the left bucket arm rod pin sensor is x The horizontal force of the left bucket arm rod pin sensor is F 1xl : ； In the above formula E Elastic modulus of the pin material; W p Bending section modulus of the pin material; K 0 Sensitivity coefficient of the strain gauge; U 1xl0 For the left bucket link pin sensor x Voltage to the bridge; U 1xli For the left bucket link pin sensor x Voltage to the bridge; During the working process, the output voltage of the left bucket arm rod pin sensor x The output voltage of the direction strain gauge is processed by the pin sensor signal processing module, transmitted to the computer through the data acquisition card, and the computer calculates the left bucket arm rod pin sensor x The direction real-time force F 1xl ; The right bucket arm pin sensor adopts the same strain gauge layout as the left bucket arm pin sensor, and the right bucket arm pin sensor is obtained in the same way x Direction real-time force F 1xr is: ； In the formula U 1xr0 For the right bucket boom pin sensor x Input voltage to the bridge; U 1xri For the right bucket boom pin sensor x Output voltage to the bridge; From the above equation, we can calculate K The total force in the direction of the pin axis x The total force in the direction of the pin axis F 1x is: ； And K The total force in the direction of the y Total force in the direction F 1y Measured from the left bucket arm pin sensor and the right bucket arm pin sensor, the specific process is: The inner hole of the left bucket boom pin sensor is in y Strain gauges are attached to the longitudinal section. R y1 , R y2 , R y3 , R y4 , R y1 and R y4 Located on the cross section CC of the left bucket boom pin sensor, and R y2 and R y3 Located on the cross section DD of the left bucket boom pin sensor, the horizontal distance between cross section CC and cross section DD is the same as the horizontal distance between cross section AA and cross section BB. L , adopt and F 1xl Using the same measurement and calculation method, the value of the left bucket boom pin sensor was determined. y Directional real-time force F 1yl and the right bucket boom pin sensor y Directional real-time force F 1yr Then F 1yl and F 1yr Add them together to find the hinge joint between the bucket and the bucket linkage. y Directional force F 1y : ； wherein U 1yl0 for the left bucket arm pin sensor y to the bridge input voltage; U 1yli for the left bucket arm pin sensor y to the bridge output voltage; U 1yr0 for the right bucket arm pin sensor y to the bridge input voltage; U 1yri for the right bucket arm pin sensor y to the bridge output voltage; Wherein Q The force received by the pin shaft x The total force in the direction F 2x And Q The force received by the pin shaft y The total force in the direction F 2y The same measurement and calculation method is adopted as F 1x And F 1y The real-time force received by the pin shaft is obtained F 2x And F 2y : ； In the formula U 2xl0 For the left bucket boom pin sensor x Input voltage to the bridge; U 2xli For the left bucket boom pin sensor x Output voltage to the bridge; U 2xr0 For the right bucket boom pin sensor x Input voltage to the bridge; U 2xri For the right bucket boom pin sensor x Output voltage to the bridge; U 2yl0 For the left bucket boom pin sensor y Input voltage to the bridge; U 2yli For the left bucket boom pin sensor y Output voltage to the bridge; U 2yr0 For the right bucket boom pin sensor y Input voltage to the bridge; U 2yri For the right bucket boom pin sensor 15.3 y Output voltage to the bridge; After obtaining all the real-time information of the forces and angles, the real-time digging resistance of the bucket is calculated F .

2. The small-sized backhoe excavator shovel digging resistance test platform according to claim 1, characterized in that, The robotic arm device includes: a forearm, a bucket electric push rod, a boom, a forearm electric push rod, a boom electric push rod, a bucket connecting rod, and a forearm connecting rod; The boom and the forearm are hinged together; the fixed end of the bucket electric push rod is fixed to the forearm, and the free end is hinged to the bucket through the bucket connecting rod, driving the bucket to move; one end of the forearm connecting rod is hinged to the forearm, and the other end is connected to the hinge point of the bucket electric push rod through the bucket connecting rod; the fixed end of the forearm electric push rod is fixed to the boom, and the free end is connected to the forearm, driving the forearm to move; the fixed end of the boom electric push rod is fixed to the workbench, and the free end is connected to the boom, driving the boom to move.

3. The small-sized backhoe excavator shovel digging resistance test platform according to claim 2, characterized in that, The measuring device includes: a bucket push rod displacement sensor, a boom push rod displacement sensor, a boom push rod displacement sensor, and four pin sensors; the bucket push rod displacement sensor is installed on the bucket electric push rod to obtain the displacement of the bucket electric push rod; the boom push rod displacement sensor is installed on the boom electric push rod to obtain the displacement of the boom electric push rod; the boom push rod displacement sensor is installed on the boom electric push rod to obtain the displacement of the boom electric push rod; the pin sensors are installed on both sides of the bucket-boom hinge point and on both sides of the bucket connecting rod-bucket hinge point.

4. The small-sized backhoe excavator shovel digging resistance test platform according to claim 3, characterized in that, The control device includes: a drive unit, a data acquisition card, a host computer, a displacement sensor signal processing module, and a pin shaft sensor signal processing module; the drive unit drives the bucket electric push rod, the boom electric push rod, and the boom electric push rod respectively; the displacement signal processing module is electrically connected to the bucket push rod displacement sensor, the boom push rod displacement sensor, and the boom push rod displacement sensor respectively; the pin shaft sensor signal processing module is electrically connected to the four pin shaft sensors respectively; the drive unit, the displacement sensor signal processing module, and the pin shaft sensor signal processing module are all electrically connected to the data acquisition card; the data acquisition card interacts with the host computer.

5. The small-sized backhoe excavator shovel digging resistance test platform according to claim 1, characterized in that, The robotic arm device includes: a forearm, a bucket electric push rod, a boom, a forearm electric push rod, a boom electric push rod, a bucket connecting rod, a forearm connecting rod, a sensor bracket, and a boom articulation frame; The boom is hinged to the forearm; the fixed end of the bucket electric push rod is fixed to the forearm, and the free end is hinged to the bucket through the bucket connecting rod, driving the bucket to move; one end of the forearm connecting rod is hinged to the forearm, and the other end is connected to the hinge point of the bucket electric push rod through the bucket connecting rod; the fixed end of the forearm electric push rod is fixed to the boom, and the free end is connected to the forearm, driving the forearm to move; the fixed end of the boom electric push rod is fixed to the boom articulation frame, and the free end is connected to the boom, driving the boom to move; the boom articulation frame is mounted on the workbench frame through the sensor bracket.

6. The small-sized backhoe excavator shovel digging resistance test platform according to claim 5, characterized in that, The measuring device includes: six force sensors; the sensor bracket is composed of a first mounting surface and a second mounting surface that are perpendicular to each other; three force sensors are respectively provided on the first mounting surface and the second mounting surface, and the three force sensors on each mounting surface are arranged in a triangle; the first component of the resistance is obtained according to the first mounting surface, and the second component of the resistance is obtained through the second mounting surface; and the left and right offsets and the tilt offsets are obtained according to the differences of the force sensors on each mounting surface.

7. A small backhoe excavator digging resistance testing platform according to claim 6, characterized in that, The control device includes: a drive unit, a force sensor transmitter group, a data acquisition card, and a host computer; the drive unit drives the bucket electric push rod, the boom electric push rod, and the boom electric push rod respectively; the force sensor transmitter group is electrically connected to the six force sensors respectively; the drive unit and the force sensor transmitter group are electrically connected to the data acquisition card respectively; the data acquisition card interacts with the host computer.

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