CN102279077A - Calibration device for double-force-source six-dimensional force sensor - Google Patents

Abstract

The invention discloses a calibration device for a double-force-source six-dimensional force sensor. The calibration device comprises a calibration working table, a first lifting mechanism, a second lifting mechanism, a loading device, a loading clamping mechanism and an L-shaped sensor base, wherein the first lifting mechanism comprises a first lifting block serving as an output end; the first lifting block is connected with one end of the loading device; the second lifting mechanism comprises a second lifting block serving as an output end; the second lifting block is connected with the other end of the loading device; two longitudinal force application rods are rigidly connected with the two lifting blocks respectively and apply vertical forces which are equal to each other and of which the directions are the same or opposite on two transverse loading square barrels respectively; the two vertical forces are converted into a combined force or a combined torque transmitted to the six-dimensional force sensor through the two transverse loading square barrels and the loading clamping mechanism; the six-dimensional force sensor is fixed on the L-shaped sensor base; and the L-shaped sensor base is arranged on the calibration working table.

Description

Calibration device for a six-dimensional force sensor with dual force sources

technical field

The invention relates to the field of a calibration loading platform for a six-dimensional force sensor, in particular to a calibration device for a six-dimensional force sensor with dual force sources.

Background technique

The six-dimensional force sensor is a force information acquisition device that can simultaneously detect three-dimensional force information (Fx, Fy, Fz) and three-dimensional moment information (Mx, My, Mz) in space. Widely used in robotics, construction and aerospace and other fields. After the design and processing of the six-dimensional force sensor is completed, in order to determine the input-output relationship of the six-dimensional force sensor, and then perform decoupling and solve various input-output characteristics, a calibration test is required. The calibration device plays an important role in the sensor development process. The accuracy of the calibration device directly restricts the measurement accuracy of the six-dimensional force sensor. The ease of use of the calibration device also directly affects the design and production cycle and cost of the six-dimensional force sensor.

At present, the sensor calibration devices developed by multi-dimensional force sensor research units at home and abroad are mainly weight type, gantry type (, double cross type, and four jack type calibration devices. Among them, weight type calibration uses weights to provide standard loading force, which can be passed The principle of pulley or lever realizes the separate calibration of single-dimensional force in each direction. It is widely used in the calibration of small and medium-scale multi-dimensional force sensors, and has the characteristics of high precision and easy operation. However, due to the physical strength of the calibration test personnel, it cannot be applied to a large number of Multi-dimensional calibration force loading of multi-dimensional force sensors. Chinese patent CN1727861A discloses a gantry-type parallel sensor calibration device, and Chinese patent CN1715856A discloses a gantry-type stepless lifting six-dimensional force sensor calibration device, which can realize large-scale, large-scale Multi-dimensional force sensor multi-dimensional calibration force loading, but must manually load the reducer and adjust the lifting pulley, can not solve the problem of automatic loading and dynamic load loading, and can not realize the separate loading of single-dimensional force in each direction. Chinese patent CN101226095A discloses a A four-jack type six-dimensional force sensor calibration device, Chinese patent CN101776506A discloses a double-cross type large-scale multi-dimensional force sensor calibration loading table, because the force adding device is a hydraulic cylinder or a jack, the volume is large, the range is high, and a heavy load is used As a force transmission element, the plate is only suitable for static and dynamic calibration loading of large and large-scale (tonnage) six-dimensional force sensors, and cannot calibrate small and medium-sized and small and medium-sized six-dimensional force sensors. Otherwise, the system introduced by the self-weight of the loading plate The error seriously affects the calibration accuracy and its processing and installation are complicated. Every time the loading direction of the single-dimensional force/moment is changed, it is necessary to move the heavy loading hydraulic cylinder or jack many times. The test operation is very complicated, and the calibration test efficiency is low. Test personnel bring heavy labor intensity. And Chinese patent CN101226095A can not realize the separate loading of single-dimensional force in each direction. Chinese patent CN101464201B discloses a kind of calibration device of six-dimensional force sensor, compact structure, high rigidity and precision, but also It cannot solve the problem of automatic loading and its dynamic load loading, and cannot realize the separate loading of single-dimensional force in each direction.

With the development of robotics, spacecraft docking, and wind tunnel tests, the research on the dynamic characteristics of six-dimensional force sensors is becoming more and more important. In order to study the dynamic characteristics of the six-dimensional force sensor, it is necessary to conduct a dynamic calibration test, that is, to use a dynamic calibration device to input a known dynamic force to the sensor. In addition, due to the unavoidable inter-dimensional coupling problem of the six-dimensional force sensor, it is more conducive to the decoupling of the six-dimensional force sensor to achieve the decoupling of the six-dimensional force sensor, thereby improving the measurement accuracy of the sensor. Due to the need to collect a large amount of data, the calibration test is labor-intensive. The automatic loading calibration device can greatly save the physical strength of the test operator, improve the test efficiency, and reduce the sensor design and production cycle.

Contents of the invention

The purpose of the present invention is to provide a calibration device for a six-dimensional force sensor with dual force sources, including a first lifting mechanism, a second lifting mechanism, a loading device, a loading clamping mechanism and an L-shaped sensor base, and the first lifting mechanism includes as The first lifting block at the output end, the first lifting block is connected with one end of the loading device, the second lifting mechanism includes the second lifting block as the output end, the second lifting block is connected with the other end of the loading device,

The loading device includes a first longitudinal application rod, a second longitudinal application rod, a first lateral loading square cylinder and a second lateral loading square cylinder, the upper end of the first longitudinal application rod is used as one end of the loading device to connect with the first lift The first lifting block of the mechanism is connected, and the first square hole sleeve is connected to the lower end of the first longitudinal force rod, the first square hole sleeve is set on the first lateral loading square cylinder and the first square hole sleeve is connected with the first A horizontal sliding connection is formed between the square cylinders, the first lateral loading square cylinder is connected to one end of the loading and clamping mechanism; the upper end of the second longitudinal force applying rod is connected to the second lifting block of the second lifting mechanism as the other end of the loading device, A second square hole sleeve is connected to the lower end of the second longitudinal force applying rod, the first square hole sleeve is set on the second lateral loading square cylinder and a horizontal sliding connection is formed between the first square hole sleeve and the second lateral loading square cylinder , the second transverse loading square cylinder is connected to the other end of the loading and clamping mechanism,

The L-shaped sensor base is set on the calibration table. The L-shaped sensor base is composed of a first arm and a second arm perpendicular to each other. The first arm is provided with a first groove for placing a six-dimensional force sensor. The second arm is provided with a second groove for placing the six-dimensional force sensor.

Compared with the prior art, the advantages of the present invention are: 1) The rotation of the motor is controlled by a PC, the standard single-dimensional force sensor measures the magnitude of the loading force, continuous dynamic and static calibration can be performed on the six-dimensional force sensor, and the operation is simple and convenient. The magnitude of the calibrated loading force is steplessly adjustable and the resolution is high; 2) A first square hole sleeve is connected to the lower end of the first longitudinal force applying rod, and the first square hole sleeve is set on the first lateral loading square cylinder and the first A horizontal sliding connection is formed between the square hole sleeve and the first transverse loading square cylinder. The first longitudinal force applying rod can apply upward or downward vertical force to the first transverse loading square cylinder, and the lower end of the second longitudinal force applying rod is connected There is a second square hole sleeve, the first square hole sleeve is set on the second laterally loaded square cylinder and a horizontal sliding connection is formed between the first square hole sleeve and the second laterally loaded square cylinder, and the second longitudinal force rod can Two horizontal loading square tubes apply upward or downward vertical force, when the six-dimensional force sensor is fixed in the first groove of the L-shaped sensor base, the first lifting block and the second lifting block drive the first longitudinal force applying rod respectively 1. The second longitudinal force bar applies upward or downward vertical forces of equal magnitude and direction to the first laterally loaded square cylinder and the second laterally loaded square cylinder gradually from zero, and the two progressively loaded vertical forces in the same direction are transformed into The resulting force in the Z direction for gradual loading is transmitted to the six-dimensional force sensor through the loading and clamping mechanism to complete the calibration of the Z direction force; the first lifting block and the second lifting block drive the first longitudinal force applying rod and the second longitudinal force respectively The bar applies upward or downward vertical forces of equal size and opposite directions to the first laterally loaded square cylinder and the second laterally loaded square cylinder from zero, and the two gradually loaded vertical forces are transformed into gradually loaded X-direction moments ( Or torque in the Y direction) is transmitted to the six-dimensional force sensor through the loading and clamping mechanism to complete the calibration of the torque in the X direction (or torque in the Y direction); rotate the six-dimensional force sensor 90 degrees along the calibration axis and fix it on the L-shaped sensor base again On the first groove of the first lifting block, the first lifting block and the second lifting block respectively drive the first longitudinal force applying rod and the second longitudinal force applying rod to the first transverse loading square cylinder and the second transverse loading square cylinder from zero to gradually Apply upward or downward vertical forces of equal size and opposite directions, and the two gradually loaded vertical forces are converted into gradually loaded Y-direction moments (or X-direction moments) and transmitted to the six-dimensional force sensor through the loading and clamping mechanism to complete the Y Calibration of directional moment (or X-direction moment). When the six-dimensional force sensor is fixed on the second groove of the L-shaped sensor base, the first lifting block and the second lifting block respectively drive the first longitudinal force applying rod and the second longitudinal force applying rod to the first lateral loading square cylinder. , The second transverse loading square cylinder starts from zero and gradually applies upward or downward vertical forces of equal magnitude and the same direction, and the two progressively loaded vertical forces in the same direction are transformed into a progressively loaded X-direction (or Y-direction) resultant force through loading The clamping mechanism is passed to the six-dimensional force sensor to complete the calibration of the X-direction force (or Y-direction force); rotate the six-dimensional force sensor 90 degrees along the calibration axis, and then fix it on the second groove of the L-shaped sensor base. If the first lifting block and the second lifting block respectively drive the first longitudinal force applying rod and the second longitudinal force applying rod to the first transverse loading square cylinder and the second transverse loading square cylinder, starting from zero and gradually applying upward or downward Equal vertical forces in the same direction, two progressively loaded vertical forces in the same direction are transformed into progressively loaded Y-direction (or X-direction) resultant forces that are transmitted to the six-dimensional force sensor through the loading and clamping mechanism to complete the Y-direction force (or X-direction) Force) calibration; make the first lifting block and the second lifting block respectively drive the first longitudinal force applying rod and the second longitudinal force applying rod to the first transverse loading square cylinder and the second transverse loading square cylinder from zero to gradually apply upward Or downward vertical forces of equal magnitude and opposite directions, the two gradually loaded vertical forces are converted into gradually loaded Z-direction moments through the loading and clamping mechanism and transmitted to the six-dimensional force sensor to complete the calibration of the Z-direction moments. In the traditional six-dimensional force sensor calibration device, the installation position of the sensor is fixed, and four loading points are required to complete the individual loading of six directions of force or moment, and a thick loading plate is used as the force transmission element, and the self-weight of the loading plate is relatively high. Large, in the calibration test, the error introduced by the self-weight of the loading plate has little influence on the calibration of the six-dimensional force sensor with a large range (several tons), but for the calibration of the six-dimensional force sensor with a small and medium range (tens of cattle), the self-weight The introduced error has a great influence, and may even produce wrong calibration results. During the test process, it is necessary to move the bulky force-adding device, such as loading hydraulic cylinders, and the calibration test operation is difficult, the test efficiency is low, and the labor intensity of the test personnel is very high. However, in the device of the present invention, the entire calibration process only needs to change the installation position of the six-dimensional force sensor on the L-shaped sensor base once, that is, the six-dimensional force sensor is respectively installed in the first groove and the second groove of the L-shaped sensor base. On the other hand, only two loading points can be used to complete the separate calibration of six directions of force or moment, that is, the first and second hollow lateral loading square cylinders are used as force transmission elements to transmit loading force, with small deflection and light weight, reducing The error introduced by the self-weight of the force transmission element and the deformation of the force transmission element after being stressed is eliminated, and the calibration accuracy is improved, so that the device of the present invention is not only suitable for the calibration of large-range six-dimensional force sensors, but also suitable for medium and small-scale six-dimensional force sensors. Calibration, during the entire calibration process, only need to change the installation direction of the six-dimensional force sensor on the L-shaped sensor base without moving the large and heavy force source (loading hydraulic cylinder, etc.) The sensor is calibrated with one-dimensional force/torque in six directions, which greatly reduces the labor intensity of the test personnel, and the calibration test efficiency is high; 3) The six-dimensional force sensor is installed on the calibration test bench through the L-shaped sensor base, and the servo motor is based on the six-dimensional The actual height of the force sensor needs to control the two lifting blocks to move up and down. The displacement stroke of the lifting block is wide, so that the device of the present invention can be used not only for the calibration of large-volume (diameter and height 0.5m~1m) six-dimensional force sensors, but also for Small and medium volume (diameter and height 5cm~0.5m) six-dimensional force sensor calibration; 4) The existing small and medium-range six-dimensional force sensor calibration device can only perform mixed force/torque The single-dimensional force or moment in the direction is calibrated separately, so the static decoupling algorithm based on the generalized inverse of the matrix can only be used for decoupling. The device can realize the separate calibration of single-dimensional force or moment in each direction. According to the test data of the separate calibration of single-dimensional force or moment in each direction, it can accurately calculate the inter-dimensional coupling relationship between the input and output of force or moment in each direction. The six-dimensional force sensor calibration and decoupling method based on error modeling is used for decoupling without complex matrix operations. The algorithm is simple and reliable, and the decoupling accuracy is high; 5) The entire calibration device has a simple structure and is easy to install, disassemble and maintain.

Description of drawings

Figure 1 is a schematic diagram of the three-dimensional structure of the present invention (calibration of Z-direction force and X- and Y-direction moments).

Fig. 2 is a schematic diagram of the three-dimensional structure of the present invention (calibration of X, Y direction force and Z direction moment).

Fig. 3 is a schematic diagram of an L-shaped sensor base in the present invention.

Fig. 4 is a schematic diagram of a six-dimensional force sensor in the present invention.

Fig. 5 is a schematic diagram of the first clamping block of the loading and clamping mechanism in the present invention.

Fig. 6 is a schematic diagram of the second clamping block of the loading and clamping mechanism in the present invention.

Fig. 7 is a schematic diagram of the assembly of the loading and clamping mechanism and the six-dimensional force sensor in the present invention.

Fig. 8 is a structural schematic diagram of the lifting mechanism in the present invention.

Fig. 9 is a schematic diagram of the calibration workbench in the present invention.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

Referring to Fig. 1, 2, it is the three-dimensional structure schematic diagram of the present invention, and calibration device comprises calibration workbench 11, first lifting mechanism, second lifting mechanism, loading device, loading clamping mechanism 14 and L-shaped sensor base 12.

The first lifting mechanism includes the first lifting block 7 as the output end, the first lifting block 7 is connected with one end of the loading device, the second lifting mechanism includes the second lifting block 8 as the output end, the second lifting block 8 is connected with the other end of the loading device Connected at one end.

The loading device comprises a first longitudinal application rod 9, a second longitudinal application rod 10, a first transverse loading square cylinder 15 and a second lateral loading square cylinder 16, and the upper end of the first longitudinal application rod 9 is used as an end of the loading device and The first lifting block 7 of the first lifting mechanism is connected, and a first square hole sleeve 91 is connected to the lower end of the first longitudinal force applying rod 9. The first square hole sleeve 91 is sleeved on the first lateral loading square cylinder 15 and the second A horizontal sliding connection is formed between one side hole sleeve 91 and the first lateral loading square cylinder 15, and the first longitudinal force applying rod 9 can apply an upward or downward vertical force to the first lateral loading square cylinder 15. The barrel 15 is connected to one end of the loading and clamping mechanism 14; the upper end of the second longitudinal applying rod 10 is connected to the second lifting block 8 of the second lifting mechanism as the other end of the loading device, and at the lower end of the second longitudinal applying rod 10 Connected with a second square hole sleeve 101, the first square hole sleeve 101 is sleeved on the second lateral loading square cylinder 16 and a lateral sliding connection is formed between the first square hole sleeve 101 and the second lateral loading square cylinder 16, and the second The longitudinal force applying rod 10 can apply an upward or downward vertical force to the second lateral loading square cylinder 16 , and the second lateral loading square cylinder 16 is connected to the other end of the loading and clamping mechanism 14 . A standard single-dimensional force sensor is installed on the upper ends of the first transverse loading square cylinder 15 and the second transverse loading square cylinder 16, which can measure the impact of the first longitudinal force applying rod 9 and the second longitudinal force applying rod 10 on the first transverse loading square cylinder 15 respectively. 1. The size and direction of the vertical force applied by the second transverse loading square cylinder 16, the accuracy of the standard single-dimensional force sensor is 0.05% F.S. or 0.02% F.S., the first transverse loading square cylinder 15 and the second transverse loading square cylinder 16 lower ends are installed with The non-contact displacement sensor is used to measure the vertical displacement of the longitudinal force rod or the lifting block. The material of the loading device is made of high-quality medium carbon steel, alloy structural steel, etc., and its mechanical properties are increased through appropriate heat treatment processes.

The L-shaped sensor base 12 is installed on the calibration workbench 11. Referring to FIG. It is formed by seam welding and machined to ensure its verticality. In order to ensure that the verticality remains unchanged after being stressed, the ribs are installed on the inner side where the first arm 121 and the second arm 122 intersect. Place the first groove 1211 of the six-dimensional force sensor 13, and the second arm 122 is provided with a second groove 1221 for placing the six-dimensional force sensor, for convenient installation of the six-dimensional force sensor 13, on the first groove 1211 There is a sensor horizontal mounting screw hole 1212, and the second groove 1221 is punched with a sensor vertical mounting screw hole 1222. The six-dimensional force sensor can be fixed in the first groove 1211 or the second groove according to the direction of the calibration force or moment. On 1221, four corners of the first arm 121 are equipped with four L-shaped sensor base fixing holes 1213, which are used to cooperate with the L-shaped sensor base mounting holes 1107 to fix the L-shaped sensor base 12 on the level of the calibration table 11 Steel plate 1101 upper surface.

Referring to FIG. 4 , the six-dimensional force sensor 13 is composed of a calibration shaft 1301 , a top cover 1302 , and a sensor base 1303 . Referring to Figures 5, 6, and 7, the loading clamping mechanism 14 is composed of a first clamping block 140 and a second clamping block 141 stacked together, and the first clamping block 140 is provided with a second clamping shaft 1301 for clamping A square groove 1401, in the first square groove 1401, the first calibration shaft connects the screw hole 1402, and the second clamping block 141 is provided with a second square groove 1411 for clamping the calibration shaft 1301. The second calibration shaft connection screw hole 1402 in the two square grooves 1411, tighten the nuts at the first calibration shaft connection screw hole 1402 and the second calibration shaft connection screw hole 1402 to ensure that the upper part of the calibration shaft 1301 is clamped; load the clamping mechanism 14 One end is embedded in the first lateral loading square cylinder 15 and is connected by two or more bolts that pass through the first lateral loading square cylinder 15 and one end of the loading clamping mechanism 14, and the other end of the loading clamping mechanism 14 is embedded in the second lateral loading The square cylinder 16 is connected by 2 or more bolts that run through the second lateral loading square cylinder 16 and the other end of the loading clamping mechanism 14 to ensure that the first lateral loading square cylinder 15, the second lateral loading square cylinder 16 and the loading The clamping mechanism 14 does not move relative to each other.

With reference to Fig. 8, the first elevating mechanism and the second elevating mechanism adopt the spiral lifting device, and the spiral elevating device is made up of the first square base 1, the first square column 3, the second square column 4, the servo motor 17, the speed reducer 18 , the first gear 19, the second gear 20, the third gear 21, the fourth gear 22, the fifth gear 23, the ball screw 24, the ball nut 25, the first guide rail 26 and the second guide rail 27, the first square The column 3 is mounted on one end of the upper surface of the first square base 1 , and the second square column 4 is loaded on the other end of the upper surface of the first square base 1 . The output shaft of the servo motor 17 is rigidly connected to the input end of the reducer 18 to reduce the speed while increasing the output torque. The output shaft of the reducer 18 is rigidly connected to the center of the first gear 19, and one side of the first gear 19 meshes with the second gear 20 , the other gear meshes with the third gear 21, the second gear 20 meshes with the fifth gear 23 at the same time, the third gear 21 meshes with the fourth gear 22 at the same time, and the centers of the five meshing gears are located on the same straight line, so that the servo The motor drives the fourth gear 22, and the fifth gear 23 rotates at the same speed and in the same direction. The central hole of the fifth gear 23 is rigidly connected with the lower end of the ball screw 24 . The cross-section of the first square column 3 and the second square column 4 is U-shaped and has the same internal structure. The ball nut 25 is threaded with the ball screw 24, and the ball nut 25 is rigidly connected with the first lifting block 7. For increasing stability, the ball The nut 25 is slidably connected with the first guide rail 26 and the second guide rail 27 guiding it on both sides of the ball screw 24 .

Referring to Figure 9, it is a schematic diagram of the calibration workbench 11 in the present invention, the calibration workbench 11 is composed of a horizontal steel plate 1101, a first vertical adapter plate 1102, a second vertical adapter plate 1103, and a third vertical adapter plate 1104 , the fourth vertical adapter plate 1105, the sensor wiring hole 1106, and the L-shaped sensor base mounting hole 1107. The sensor wiring hole 1106 is used to place the output cable of the six-dimensional force sensor. The two ends on the left side of the horizontal steel plate 1101 are rigidly connected to the first vertical adapter plate 1102 and the second vertical adapter plate 1103 at right angles respectively, and the two ends on the right side are respectively connected to the third vertical adapter plate 1104 and the second vertical adapter plate 1104 respectively. The four vertical adapter plates 1105 are rigidly connected at right angles, and the machining process adopts seamless welding, and the verticality is guaranteed. Calibration workbench 11 passes through first vertical adapter plate 1102, second vertical adapter plate 1103, third vertical adapter plate 1104, fourth vertical adapter plate 1105 and first box-shaped column 3, second vertical adapter plate 1105 respectively Two box-shaped columns 4, the third box-shaped columns 5, and the side threads of the fourth box-shaped columns 6 are fixed between the four box-shaped columns. In order to ensure that no deformation occurs when the horizontal steel plate 1101 is stressed, the lower surface of the horizontal steel plate 1101 is covered with reinforcing ribs. The surface of the horizontal steel plate 1101 has an L-shaped sensor base mounting hole 1107 for threaded connection with the L-shaped sensor base 12 .

When the six-dimensional force sensor 13 is fixed on the first groove 1211 of the L-shaped sensor base 12, the first lifting block 7 and the second lifting block 8 drive the first longitudinal force application rod 9 and the second longitudinal force application rod 10 respectively. To the first transverse loading square cylinder 15 and the second transverse loading square cylinder 16, apply upward or downward vertical forces in the same direction and equal in size gradually from zero, and the two progressively loaded vertical forces in the same direction are transformed into progressively loaded Z The resultant force in the direction is transmitted to the six-dimensional force sensor 13 through the loading and clamping mechanism 14 to complete the calibration of the force in the Z direction; the first lifting block 7 and the second lifting block 8 drive the first longitudinal force applying rod 9 and the second longitudinal force applying rod 9 respectively. The rod 10 gradually applies upward or downward vertical forces of equal magnitude and opposite directions to the first laterally loaded square cylinder 15 and the second laterally loaded square cylinder 16 from zero, and the two gradually loaded vertical forces are converted into gradually loaded X Direction torque (or Y direction torque) is transmitted to the six-dimensional force sensor 13 through the loading and clamping mechanism 14, and the calibration of the X direction torque (or Y direction torque) is completed; the six-dimensional force sensor 13 is rotated 90 degrees along the calibration axis 1301, and again It is fixed on the first groove 1212 of the L-shaped sensor base, so that the first lifting block 7 and the second lifting block 8 respectively drive the first longitudinal force applying rod 9 and the second longitudinal force applying rod 10 to the first transverse loading direction. Cylinder 15 and the second transverse loading square cylinder 16 start from zero and gradually apply upward or downward vertical forces of equal magnitude and opposite directions, and the two gradually loaded vertical forces are converted into gradually loaded Y-direction moments (or X-direction moments) The calibration of the torque in the Y direction (or the torque in the X direction) is completed by transferring it to the six-dimensional force sensor 13 through the loading and clamping mechanism 14 .

When the six-dimensional force sensor 13 is fixed on the second groove 1221 of the L-shaped sensor base, the first lifting block 7 and the second lifting block 8 respectively drive the first longitudinal force applying rod 9 and the second longitudinal applying force rod 10 pairs The first laterally loaded square cylinder 15 and the second laterally loaded square cylinder 16 gradually apply upward or downward vertical forces in the same direction of equal magnitude from zero, and the two progressively loaded vertical forces in the same direction are converted into progressively loaded X directions. (or Y direction) resultant force is transmitted to the six-dimensional force sensor 13 through the loading and clamping mechanism 14, and the calibration of the X-direction force (or Y-direction force) is completed; the six-dimensional force sensor 13 is rotated 90 degrees along the calibration axis 1301, and then fixed on the On the second groove 1221 of the L-shaped sensor base, if the first lifting block 7 and the second lifting block 8 respectively drive the first longitudinal force applying rod 9 and the second longitudinal force applying rod 10 to the first lateral loading square cylinder 15 1. The second horizontally loaded square tube 16 starts from zero and gradually applies upward or downward vertical forces of equal magnitude and direction, and the two progressively loaded vertical forces in the same direction are transformed into progressively loaded Y-direction (or X-direction) resultant forces through The loading and clamping mechanism 14 is transmitted to the six-dimensional force sensor 13 to complete the calibration of the force in the Y direction (or the force in the X direction); the first lifting block 7 and the second lifting block 8 drive the first longitudinal force applying rod 9 and the second Longitudinal force applying bar 10 applies upward or downward vertical forces of equal and opposite directions to the first horizontal loading square cylinder 15 and the second lateral loading square cylinder 16 gradually from zero, and the vertical force of two progressively loaded vertical forces is transformed into step by step The loaded torque in the Z direction is transmitted to the six-dimensional force sensor 13 through the loading and clamping mechanism 14 to complete the calibration of the torque in the Z direction.

During the whole calibration test process, two servo motors are controlled by a PC, and the magnitude and positive and negative directions of the loading force are measured by a standard unidirectional force sensor, and the position of the fixture is detected by a non-contact displacement sensor. And by installing the six-dimensional force sensor 13 on the first groove 1211 or the second groove 1221 of the L-shaped sensor base 12, the three directional forces and three directional moments can be accurately calibrated respectively. According to the test calibration data of single-dimensional force loading in each direction, the input and output of the six-dimensional force sensor 13 constitute a linear steady system. Starting from the essence of inter-dimensional coupling, the inter-dimensional coupling model of the six-dimensional force sensor 13 is established.

The output voltage of each channel is first subtracted from the part of the voltage value introduced by the coupling between the interfering force dimensions, that is, the coupling error is eliminated, and then divided by k _ii to find the force, and the decoupling calculation between the various forces is completed. As shown in formula (1).

  式中                (1)

In the formula (1)

The decoupling of formula (1) needs to know the coupling interference force vector, but in the actual decoupling process, the known quantity is the electrical signal output by each channel, and the magnitude of each force input is an unknown quantity, so the output voltage value must be used instead of the coupling interference. The decoupling formula is shown in formula (2).

                         (2)

(2)

可由静态标定试验数据进行一元线性拟合获得。最后将所测电压带入式(2)中则完成了解耦。 All undetermined constants in formula (2) are

It can be obtained by unary linear fitting of the static calibration test data. Finally, bring the measured voltage into formula (2) to complete the decoupling.

Claims (3)

1. A calibration device for a six-dimensional force sensor with dual force sources, comprising: a calibration workbench (11), characterized in that the calibration device also includes a first lifting mechanism, a second lifting mechanism, a loading device, a loading clamp Mechanism (14) and L-shaped sensor base (12), the first lifting mechanism includes the first lifting block (7) as the output end, the first lifting block (7) is connected with one end of the loading device, the second lifting mechanism includes as The second lifting block (8) at the output end, the second lifting block (8) is connected with the other end of the loading device, The loading device includes a first longitudinal application rod (9), a second longitudinal application rod (10), a first lateral loading square cylinder (15) and a second lateral loading square cylinder (16), the first The upper end of the longitudinal force applying rod (9) is connected to the first lifting block (7) of the first lifting mechanism as one end of the loading device, and the first square hole sleeve (91) is connected to the lower end of the first longitudinal force applying rod (9). ), the first square hole sleeve (91) is sleeved on the first lateral loading square cylinder (15) and a lateral sliding connection is formed between the first square hole sleeve (91) and the first lateral loading square cylinder (15), the first A lateral loading square tube (15) is connected to one end of the loading clamping mechanism (14); the upper end of the second longitudinal force applying rod (10) is used as the other end of the loading device to connect with the second lifting block of the second lifting mechanism ( 8) Connection, the second square hole sleeve (101) is connected to the lower end of the second longitudinal force applying rod (10), the first square hole sleeve (101) is sleeved on the second transverse loading square cylinder (16) and the second A horizontal sliding connection is formed between one hole sleeve (101) and the second lateral loading square cylinder (16), and the second lateral loading square cylinder (16) is connected with the other end of the loading clamping mechanism (14), The L-shaped sensor base (12) is set on the calibration table (11), and the L-shaped sensor base (12) is composed of a first arm (121) and a second arm (122) perpendicular to each other. The arm (121) is provided with a first groove (1211) for placing a six-dimensional force sensor, and the second arm (122) is provided with a second groove (1221) for placing a six-dimensional force sensor. 2. The calibration device of the dual force source six-dimensional force sensor according to claim 1, characterized in that, the loading and clamping mechanism (14) consists of the first clamping block (140) and the second clamping block (140) stacked together Composed of two clamping blocks (141), the first clamping block (140) is provided with a first square groove (1401) for clamping the calibration shaft of the sensor, and the first calibration in the first square groove (1401) The shaft connection screw hole (1402), the second clamping block (141) is provided with a second square groove (1411) for clamping the calibration shaft of the sensor, and the second calibration shaft is connected in the second square groove (1411) Screw hole (1402); one end of the loading and clamping mechanism (14) is embedded in the first transverse loading square cylinder (15) and consists of 2 or more penetrating through the first transverse loading square cylinder (15) and the loading and clamping mechanism ( 14) Bolt connection at one end, the other end of the loading and clamping mechanism (14) is embedded in the second lateral loading square cylinder (16) and is composed of 2 or more penetrating second lateral loading square cylinders (16) and loading clamping Bolt connection at the other end of the mechanism (14). 3. The calibration device of the dual force source six-dimensional force sensor according to claim 1 or 2, wherein the first lifting mechanism and the second lifting mechanism adopt a spiral lifting device, and the lifting device includes a first square Base (1), first square column (3), second square column (4), servo motor (17), reducer (18), first gear (19), second gear (20), the first Third gear (21), fourth gear (22), fifth gear (23), ball screw (24), ball nut (25), first guide rail (26) and second guide rail (27), first party The square column (3) is loaded on one end of the upper surface of the first square base (1), the second square column (4) is loaded on the other end of the upper surface of the first square base (1), and the servo motor (17) The output shaft of the reducer (18) is rigidly connected to the input end of the reducer (18), the output shaft of the reducer (18) is rigidly connected to the center of the first gear (19), and one side of the first gear (19) meshes with the second gear (20) , the other side meshes with the third gear (21), the second gear (20) meshes with the fifth gear (23) at the same time, the third gear (21) meshes with the fourth gear (22) at the same time, and the five meshing gears The gear centers are located on the same straight line, the center hole of the fifth gear (23) is rigidly connected to the lower end of the ball screw (24), the internal structure of the first square column (3) is the same as that of the second square column (4), and the ball nut (25) is threadedly matched with the ball screw (24), the ball nut (25) is slidingly connected with the first guide rail (26) and the second guide rail (27), and the ball nut (25) is rigidly connected with the output end of the lifting mechanism.

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