A multi-degree-of-freedom precise measurement device and measurement method in large-scale space

Abstract

The present invention discloses a multi-degree-of-freedom precise measurement device and a measurement method in a large-scale space, comprising a carrying platform, an articulated assembly is installed at one end of the top surface of the carrying platform, a telescopic assembly is hinged at one end of the top surface of the articulated assembly, a plurality of movable joints connected in series are installed at one end of the telescopic assembly away from the articulated assembly, a detection sensor is fixedly connected at one end of the movable joint away from the telescopic assembly, a terminal control system is installed at one end of the top surface of the carrying platform away from the articulated assembly, the detection sensor is electrically connected to the terminal control system, a laser radar is installed at the top of the terminal control system, a wireless communication system is installed on the carrying platform, a distance sensor is installed on one side of the detection sensor, and a serial port camera is installed on the side of the distance sensor. The present invention solves the problem that personnel cannot enter the site at will to quickly carry out pollution measurement work in the case of large-scale space pollution.

Description

Technical Field

[0001] This invention relates to the field of radiation measurement, and in particular to a large-scale, multi-degree-of-freedom precision measurement device and method. Background Art

[0002] During the operation, maintenance, decommissioning, and nuclear emergency response of various nuclear facilities, it is often necessary to measure large-scale, large-area radioactive contamination data in a timely manner. Radioactive contamination poses certain hazards to human health and safety, hindering human measurement work. In recent years, a small number of measuring devices have been developed domestically. Large-scale radioactive measuring devices have limited access dimensions, and small measuring robots have limited operating space; both suffer from low automation levels and high development costs. Existing radioactive measurement methods often require personnel to enter contaminated sites to personally operate surface contamination monitoring equipment for radiation measurements. Spatial point coordinates require measuring tools, resulting in low positioning accuracy. At higher locations, ladders or other equipment are needed, or high-altitude measurements are impossible. With the increasing frequency of various measurement tasks, there is an urgent need to design a large-scale, multi-degree-of-freedom, precise measuring device and method to avoid the harm caused by radioactive contaminants to personnel. Summary of the Invention

[0003] The purpose of this invention is to provide a precise measurement device and method for multiple degrees of freedom in a large-scale space, so as to solve the problems existing in the prior art.

[0004] To achieve the above objectives, the present invention provides the following solution: The present invention provides a large-scale, multi-degree-of-freedom precision measurement device, comprising a mounting platform. A hinge assembly is mounted on one end of the top surface of the mounting platform. A telescopic assembly is hinged to one end of the top surface of the hinge assembly. A plurality of sequentially connected movable joints are mounted on the end of the telescopic assembly away from the hinge assembly. A detection sensor is fixedly connected to the end of each movable joint away from the telescopic assembly. A terminal control system is mounted on the end of the top surface of the mounting platform away from the hinge assembly. The detection sensor is electrically connected to the terminal control system. The hinge assembly, telescopic assembly, and movable joints are electrically connected to the terminal control system via a controller. A lidar is mounted on the top of the terminal control system. A wireless communication system is mounted on the mounting platform. A distance sensor is mounted on one side of the detection sensor. A serial port camera is mounted on the side of the distance sensor. The detection sensor, the distance sensor, and the serial port camera are electrically connected to the terminal control system.

[0005] Preferably, the carrying platform includes an upper cover plate, the top surface of the upper cover plate is slidably connected to a sliding support plate through a slide rail, the top surface of the upper cover plate is fixedly connected to a horizontal push rod, the output end of the horizontal push rod is fixedly connected to the bottom surface of the sliding support plate through a screw, the motor seat of the horizontal push rod is fixedly connected to the top surface of the upper cover plate, the hinge assembly is installed at one end of the top surface of the sliding support plate, and the terminal control system is fixedly connected to the end of the upper cover plate away from the sliding support plate.

[0006] Preferably, the hinge assembly includes a hinge base fixedly connected to the top of the sliding support plate, a support frame fixedly connected to the bottom end of the telescopic assembly, the bottom end of the support frame being hinged to the top end of the hinge base, an electric push rod being hinged to the top end of the sliding support plate, and the output end of the electric push rod being hinged to the middle of the support frame.

[0007] Preferably, the telescopic assembly includes a telescopic push rod, the support frame is fixedly connected to the bottom end of the telescopic push rod, the top end of the telescopic push rod is fixedly connected to a fixed plane, and the movable joint is installed on the side of the fixed plane away from the telescopic push rod.

[0008] Preferably, the movable joint includes a first joint, a second joint and a third joint, and the first joint is fixedly connected to the fixed plane; a clamping bracket is installed on the detection sensor, and the detection sensor is fixedly connected to the third joint through the clamping bracket, and lightweight brackets are rotatably connected to the first joint and the third joint respectively, and the lightweight bracket on the first joint is rotatably connected to the second joint at one end away from the first joint, and the lightweight bracket on the third joint is fixedly connected to the second joint at one end away from the third joint.

[0009] Preferably, the first joint includes a first mounting frame and a second mounting frame, and the first mounting frame and the second mounting frame are respectively fixedly connected with a joint motor, the output end of the joint motor on the first mounting frame passes through the first mounting frame and is transmission-connected with the second mounting frame, and the joint motor on the second mounting frame passes through the second mounting frame and is rotationally connected to the lightweight bracket; the second joint and the third joint have the same structure as the first joint, and the clamping bracket is fixedly connected to the first mounting frame of the third joint.

[0010] A measurement method for a large-scale, multi-degree-of-freedom precision measurement device includes the following steps:

[0011] Step 1: The mounting platform is mounted on the ground mobile platform. The host computer of the terminal control system sends a platform motion control command to control the ground mobile platform to move to the vicinity of the point to be measured.

[0012] Step two, the terminal control system controls the movement of the hinge assembly, the telescopic assembly and the movable joint through the controller, so that the detection sensor accurately approaches the point to be measured;

[0013] Step 3: The origin of the reference coordinate system is O1, with the projection of the geometric center of the top surface of the mounting platform onto the ground as the reference coordinate origin. The positive direction of the x-axis is along the length of the mounting platform and points towards the lidar. The coordinate system is a right-handed coordinate system.

[0014] Step 4: Calculate the coordinates P1 of O1 using the distance and orientation information from the controller, the lidar, the inertial sensor installed in the controller for controlling the movement of the platform, and the odometer.

[0015] Step 5: Taking the center of the rotation axis of the hinge assembly as the origin O2 of the movable joint, its coordinates P2 = P1 + P can be determined. 机械安装位置 +P 水平推杆位置 ; Determine the M-DH coordinate parameter table using the structural parameters of each of the movable joints, and substitute them into the coordinate transformation matrix. This allows us to obtain the description of a point in coordinate system i in coordinate system i-1, where the z-axis is defined as the direction of each rotation or translation axis, and the x-axis is the common perpendicular of the two rotation axes, i.e., the connecting rod. In the formula: i represents the i-th joint, a i-1 For the x i-1 Direction z i-1 With z i The distance between i-1 For x i-1 Look at the direction z i-1 With z i Angle between i For along z i Direction x i-1 with x i The distance between i For z i Look in the direction of x i-1 with x i Angle between

[0016]

[0017] The coordinate transformation matrix between the center point Q of the detection sensor (13) plane and the origin O2 is: in [uvw] 3×3 is the attitude angle matrix of point Q, q 3×1 That is, the position vector of point Q; the terminal control system acquires and calculates the angle θ of each of the moving joints. i and the telescopic distance d of the telescopic assembly i ,pass Solve and determine the position of the center coordinate of the detection sensor in space as P=P2+q 3×1 ;

[0018] Step 6: Set the RGB component values ​​and the one-dimensional linear function so that the one-dimensional data of the detection sensor is mapped one-to-one with the RGB value. The host computer of the terminal control system draws a color point cloud map in real time in the three-dimensional space according to the center coordinate P of the detection sensor and the detection data of the detection sensor.

[0019] Preferably, the specific process of step 2 is: in the process of approaching the plane to be measured, the distance sensor is used to maintain the measuring distance and avoid collision. When the distance is less than 1 cm, the host computer software of the terminal control system alarms. When the distance is detected to be less than 5 mm, the terminal control system locks the end joint control instruction. After the host computer software unlocks the state, the end joint control instruction is restored. At the same time, a serial port camera is installed next to the distance sensor and connected to the sub-controller to assist in observing the on-site detection situation. The relative position of the detection sensor and the surface to be measured can remain stable for a long time, avoiding unstable measurement factors such as jitter during manual operation.

[0020] Preferably, the specific process of step four is as follows: When the controller is initialized, the lidar scans the distance and orientation information of the closed space contour; the inertial sensor installed in the controller for controlling the movement of the platform outputs the acceleration and angular velocity information of the platform; the odometer installed in the controller for controlling the movement of the platform outputs the distance traveled by the platform; and the particle filtering method is used to update the trajectory state p(x) of the platform at the current time t in real time based on the pose, map, and platform motion model of the previous moment. 1:t |u 1:t-1 ,z 1:t ), calculate and update the two-dimensional grid map data p(m|u using trajectory status and lidar data 1:t ,z 1:t ), where u is the control data, z is the observation data, x is the current state, and m is the map data; the onboard platform can match the position and angle in the map according to the controller output data at the current moment.

[0021] Preferably, the terminal control system is designed with a center of gravity adjustment calculation module. By acquiring the angle of each of the movable joints, and based on the weight of each movable joint and the fulcrum position of the mounting platform, the overall overturning moment of the device is calculated. When the overturning moment is greater than or equal to a set overturning threshold, the mounting platform moves to ensure that the center of gravity projection is located within the front and rear fulcrum interval of the mounting platform, thus solving the problem of insufficient counterweight and overturning risk caused by personnel operation.

[0022] The present invention discloses the following technical effects:

[0023] 1. In use, the present invention involves mounting the platform on a ground mobile platform, with the host computer of the terminal control system sending motion control commands to move the platform to the vicinity of the point to be measured. The terminal control system controls the movement of the hinge components, telescopic components, and movable joints through the controller, ensuring that the detection sensor accurately approaches the point to be measured. Using the projection of the geometric center of the mounting platform onto the ground as the origin of the reference coordinates, the planar coordinates of the detection sensor are calculated using a spatial position calculation method. The coordinates of the mounting platform are calculated using the distance and orientation information from the controller and the lidar. M-DH coordinates are established based on the dimensions of each movable joint. The terminal control system collects and calculates the angles of each movable joint and the telescopic distance of the telescopic components, and determines the center coordinates of the detection sensor through coordinate calculation. RGB component values ​​are arbitrarily set in three-dimensional space. Based on the center coordinates of the detection sensor and the detection data from the detection sensor, the host computer of the terminal control system maps the one-dimensional range value of the detection sensor to the RGB values ​​one-to-one, and draws a color point cloud map in real time.

[0024] 2. This invention can realize the coordinate positioning and real-time continuous measurement of any contaminated point or surface, such as wall, top, ground, or object surface, within a large spatial scale (height > 8m).

[0025] 3. The present invention, through the design of multiple connected movable joints, enables the device to meet the requirements of various irregular surfaces for the degree of freedom of measuring instruments.

[0026] 4. The present invention can obtain the location of pollution sources and pollution values, draw three-dimensional graphics of the pollution space in real time, and automatically store the data to intuitively assess the safety status of the site.

[0027] 5. This invention achieves collision prevention for the detector by detecting a distance threshold using a distance sensor, and avoids the risk of tipping over when the device is detecting over long distances by using an automatic center of gravity adjustment method.

[0028] 6. This invention solves the problem that personnel cannot freely enter the site to quickly carry out pollution measurement work in the case of large-scale spatial pollution, and realizes remote control and intelligent assisted operation, thus avoiding personnel contamination. Attached Figure Description

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0030] Figure 1 This is an isometric view of the present invention;

[0031] Figure 2 for Figure 1 Enlarged view of point A in the middle;

[0032] Figure 3 This is a schematic diagram of the structure of the platform on which the present invention is mounted;

[0033] Figure 4 Schematic diagram of the structure of the measuring method of the present invention;

[0034] Figure 5 This is a coordinate relationship diagram of the measuring device of the present invention;

[0035] Figure 6 This is the M-DH coordinate parameter table.

[0036] The components include: 1. Terminal control system; 2. LiDAR; 3. Top cover plate; 4. Slide rail; 5. Sliding support plate; 6. Horizontal push rod; 7. Motor base; 8. Hinge base; 9. Support frame; 10. Electric push rod; 11. Telescopic push rod; 12. Fixed plane; 13. Detection sensor; 14. Clamping bracket; 15. Distance sensor; 16. First joint; 17. Second joint; 18. Third joint; 19. Lightweight bracket; 161. First mounting bracket; 162. Second mounting bracket; 163. Joint motor. Detailed Implementation

[0037] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0038] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0039] Example 1:

[0040] Reference Figure 1-3This invention provides a large-scale, multi-degree-of-freedom precision measurement device, comprising a mounting platform, a hinge assembly mounted on one end of the top surface of the mounting platform, a telescopic assembly hinged to one end of the top surface of the hinge assembly, a plurality of sequentially connected movable joints mounted on the end of the telescopic assembly away from the hinge assembly, a detection sensor 13 fixedly connected to the end of the movable joints away from the telescopic assembly, a terminal control system 1 mounted on the end of the top surface of the mounting platform away from the hinge assembly, the detection sensor 13 electrically connected to the terminal control system 1, the hinge assembly, the telescopic assembly, and the movable joints electrically connected to the terminal control system 1 via a controller, a lidar 2 mounted on the top of the terminal control system 1, a wireless communication system mounted on the mounting platform, a distance sensor 15 mounted on one side of the detection sensor 13, a serial port camera mounted on the side of the distance sensor 15, and the detection sensor 13, the distance sensor 15, and the serial port camera electrically connected to the terminal control system 1 respectively.

[0041] In use, to measure any contaminated point such as a wall, top, ground, or object surface, the mounting platform is mounted on a ground-based mobile platform. The host computer of the terminal control system 1 sends motion control commands to the platform, controlling the ground-based mobile platform to move near the point to be measured. The terminal control system 1 controls the movement of the hinge assembly, telescopic assembly, and movable joints through the controller, so that the detection sensor 13 accurately approaches the point to be measured. Using the projection of the geometric center of the top surface of the mounting platform onto the ground as the origin of the reference coordinates, the distance and direction of the probe are measured through the controller, the lidar, and the inertial sensor and odometer installed in the controller for controlling the movement of the mounting platform. The system calculates the position of the reference coordinates in space using the position information; it determines the M-DH coordinate parameter table through the structural parameters of each movable joint; the terminal control system 1 collects and calculates the angles of each movable joint and the extension distance of the telescopic component; it determines the center coordinates and position in space of the detection sensor 13 through coordinate calculation; it sets RGB component values ​​and a one-dimensional linear function to map the one-dimensional data of the detection sensor 13 to the RGB values ​​one-to-one; and the host computer of the terminal control system 1 draws a color point cloud map in real time in three-dimensional space based on the center coordinates P of the detection sensor 13 and the detection data of the detection sensor 13.

[0042] The detection sensor 13 is a surface contamination meter.

[0043] When approaching the surface to be measured, distance sensor 15 is used to maintain the measurement distance and avoid collisions. When the distance is less than 1 cm, the host computer software of terminal control system 1 issues an alarm. When the distance is less than 5 mm, terminal control system 1 locks the end joint control instructions. After the host computer software unlocks the state, the end joint control instructions are restored. A serial port camera is installed next to distance sensor 15 and connected to the sub-controller to assist in observing the on-site detection situation. The relative position of the instrument and the surface can be maintained stable over time, avoiding unstable measurement factors such as jitter during manual operation.

[0044] The wireless communication system consists of three devices, primarily to address communication interruptions caused by building shielding and obstruction. The first device is fixed anywhere on the upper cover plate 3, the second is fixed at an entrance or exit within the test environment where the mobile platform can freely pass, and the third is fixed in a work environment away from the operating location with access to a local area network. The wireless communication system can adopt a mesh networking type or a point-to-multipoint type, with the second device set as the central network, connecting to the terminal control system 1 via a network port to exchange data.

[0045] To further optimize the solution, the mounting platform includes an upper cover plate 3, the top surface of the upper cover plate 3 is slidably connected to the sliding support plate 5 through a slide rail 4, the top surface of the upper cover plate 3 is fixedly connected to a horizontal push rod 6, the output end of the horizontal push rod 6 is fixedly connected to the bottom surface of the sliding support plate 5 through a screw, the motor seat 7 of the horizontal push rod 6 is fixedly connected to the top surface of the upper cover plate 3, the hinge assembly is installed at one end of the top surface of the sliding support plate 5, and the terminal control system 1 is fixedly connected to the end of the upper cover plate 3 away from the sliding support plate 5.

[0046] To further optimize the solution, the hinge assembly includes a hinge base 8 fixedly connected to the top of the sliding support plate 5, the bottom end of the telescopic assembly is fixedly connected to the support frame 9, the bottom end of the support frame 9 is hinged to the top of the hinge base 8, the top of the sliding support plate 5 is hinged to an electric push rod 10, and the output end of the electric push rod 10 is hinged to the middle of the support frame 9.

[0047] A further optimized solution is that the telescopic assembly includes a telescopic push rod 11, the support frame 9 is fixedly connected to the bottom end of the telescopic push rod 11, the top of the telescopic push rod 11 is fixedly connected to a fixed plane 12, the movable joint is installed on the side of the fixed plane 12 away from the telescopic push rod 11, and one side of the detection sensor 13 is fixedly connected to a clamping bracket 14, and the clamping bracket 14 is fixedly connected to the movable joint.

[0048] Controllers are installed on the telescopic push rod 11, the electric push rod 10, and the horizontal push rod 6, respectively.

[0049] A further optimized scheme includes a movable joint comprising a first joint 16, a second joint 17, and a third joint 18. The first joint 16 is fixedly connected to the fixed plane 12. A clamping bracket 14 is mounted on the detection sensor 13, and the detection sensor 13 is fixedly connected to the third joint 18 through the clamping bracket 14. Lightweight brackets 19 are rotatably connected to the first joint 16 and the third joint 18, respectively. The end of the lightweight bracket 19 on the first joint 16 away from the first joint 16 is rotatably connected to the second joint 17, and the end of the lightweight bracket 19 on the third joint 18 away from the third joint 18 is fixedly connected to the second joint 17.

[0050] In a further optimized design, the first joint 16 includes a first mounting bracket 161 and a second mounting bracket 162. A joint motor 163 is fixedly connected to the first mounting bracket 161 and the second mounting bracket 162 respectively. The output end of the joint motor 163 on the first mounting bracket 161 passes through the first mounting bracket 161 and is connected to the second mounting bracket 162 for transmission. The joint motor 163 on the second mounting bracket 162 passes through the second mounting bracket 162 and is rotatably connected to the lightweight support 19. The second joint 17 and the third joint 18 have the same structure as the first joint 16. The clamping support 14 is fixedly connected to the first mounting bracket 161 of the third joint 18.

[0051] A lightweight bracket 19 is installed between the second mounting bracket 162 on the first joint 16 and the second mounting bracket 162 on the second joint 17, and the lightweight bracket 19 is rotatably connected to both second mounting brackets 162; a lightweight bracket 19 is provided between the first mounting bracket 161 on the second joint 17 and the second mounting bracket 162 on the third joint 18, one end of the lightweight bracket 19 is fixedly connected to the first mounting bracket 161 on the second joint 17, and the other end of the lightweight bracket 19 is rotatably connected to the second mounting bracket 162 on the third joint 18.

[0052] In order to be able to deeply measure the surface of special parts, multiple movable joints in series are designed according to the surface's requirements for joint freedom. The coordination of three sections of joints gives the movable joints six degrees of freedom.

[0053] A working method of a multi-degree-of-freedom precision measurement device in a large-scale space, wherein a carrying platform is mounted on a ground mobile platform, a wireless communication system relay module is placed at the entrance of a shielding body, and a multi-degree-of-freedom remote control and a computer host interface are used to control the ground mobile platform to move to the vicinity of a point to be measured; a terminal control system 1 controls the movement of an articulated component, a telescopic component, and a movable joint through a controller, so that a detection sensor 13 is accurately close to the point to be measured; in the process of approaching the plane to be measured, a distance sensor 15 is used to maintain the measurement distance and avoid collision; when the distance is less than 1 cm, the host computer software of the terminal control system 1 alarms; when the distance is detected to be less than 5 mm, the terminal control system 1 locks the end joint control instruction, and after the host computer software is unlocked, the end joint control instruction is restored. ; At the same time, a serial camera is installed next to the distance sensor 15 and connected to the sub-controller to assist in observing the on-site detection situation. The relative position of the detection sensor 13 and the surface to be measured can remain stable for a long time, avoiding unstable measurement factors such as shaking during manual operation; a rectangular coordinate system is established with the projection of the geometric center of the carrying platform including the upper cover 3 on the ground as the reference coordinate origin O1. The positive direction of the x-axis is the direction of the horizontal push rod 6 and points to the laser radar 2. The coordinate system is a right-hand coordinate system; when the controller is initialized, the laser radar 2 scans the distance and orientation information of the outline of the closed space, and the inertial sensor set in the controller for controlling the movement of the carrying platform outputs the acceleration and angular velocity information of the carrying platform, and the odometer set in the controller for controlling the movement of the carrying platform outputs the moving distance information of the carrying platform. The particle filtering method is used to update the trajectory state p(x 1:t |u 1:t-1 ,z 1:t ), calculate and update the two-dimensional grid map data p(m|u using trajectory status and lidar data 1:t ,z 1:t (), where u is control data, z is observation data, x is the current state, and m is map data; the platform can match the position and angle in the map based on the controller output data at the current moment; taking the center of the rotation axis of the hinged base 8 as the coordinate origin O2 of the movable joint, its coordinates P2 = P1 + P can be determined. 机械安装位置 +P 水平推杆位置 ; Determine the M-DH coordinate parameter table using the structural parameters of each movable joint, and substitute them into the coordinate transformation matrix. This allows us to obtain the description of a point in coordinate system i in coordinate system i-1, where the z-axis is defined as the direction of each rotation or translation axis, and the x-axis is the common perpendicular of the two rotation axes, i.e., the connecting rod. In the formula: i represents the i-th joint, a i-1 For the x i-1 Direction z i-1 With z i The distance between i-1 For xi-1 Look at the direction z i-1 With z i Angle between i For along z i Direction x i-1 with x i The distance between i For z i Look in the direction of x i-1 with x i Angle between

[0054]

[0055] The coordinate transformation matrix between the center point Q of the detection sensor 13 plane and the origin O2 is: in [uvw] 3×3 is the attitude angle matrix of point Q, q 3×1 That is, the position vector of point Q. The terminal control system 1 acquires and calculates the angle θ of each moving joint. i And the telescopic distance d of the telescopic component i ,pass The center coordinates of the detection sensor 13 are calculated to be P = P2 + q in space. 3×1 The RGB component values ​​and one-dimensional linear function are set so that the one-dimensional data of the detection sensor 13 is mapped one-to-one with the RGB values. The host computer of the terminal control system 1 draws a color point cloud map in three-dimensional space in real time based on the center coordinate P of the detection sensor 13 and the detection data of the detection sensor 13.

[0056] Example 2

[0057] Unlike Embodiment 1, since the telescopic push rod 11 has a longer distance and the data transmission distance of the detection sensor 13 is limited, a sub-controller can be installed at the clamping bracket 14. The sub-controller exchanges data with the terminal control system 1 through a wireless serial port, reads the detection data of the detection sensor 13 through a second serial port, controls the movement of the movable joint using PWM data, and obtains the distance data of the controller on the movable joint through a third serial port.

[0058] Example 3

[0059] Unlike Embodiments 1 and 2, small mobile platforms typically have limited self-weight and load-bearing capacity. To address the risks of overturning due to insufficient counterweight and personnel operation, the terminal control system 1 is equipped with a center of gravity adjustment calculation module. By acquiring the angles of each movable joint and calculating the overall overturning moment of the device based on the weight of each movable joint and the fulcrum position of the platform, the platform moves when the overturning moment is greater than or equal to a set overturning threshold, ensuring that the center of gravity projection is located within the front and rear fulcrum interval of the platform, thus resolving the issues of insufficient counterweight and overturning risks caused by personnel operation.

[0060] In the description of the present invention, it should be understood that the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0061] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art shall fall within the scope of protection defined by the claims of the present invention.

Claims

1. A multi-degree-of-freedom precise measurement device in a large-scale space, characterized in that: The invention comprises a carrying platform, wherein a hinge assembly is installed at one end of the top surface of the carrying platform, a telescopic assembly is hingedly connected to one end of the top surface of the hinge assembly, a plurality of movable joints connected in series are installed at one end of the telescopic assembly away from the hinge assembly, a detection sensor (13) is fixedly connected to one end of the movable joint away from the telescopic assembly, a terminal control system (1) is installed at one end of the top surface of the carrying platform away from the hinge assembly, the detection sensor (13) is electrically connected to the terminal control system (1), the hinge assembly, the telescopic assembly and the movable joint are electrically connected to the terminal control system (1) through a controller, a laser radar (2) is installed at the top of the terminal control system (1), a wireless communication system is installed on the carrying platform, a distance sensor (15) is installed on one side of the detection sensor (13), a serial port camera is installed on the side of the distance sensor (15), and the detection sensor (13), the distance sensor (15) and the serial port camera are electrically connected to the terminal control system (1) respectively; The measuring method of the device comprises the following steps: Step 1: The carrying platform is mounted on the ground mobile platform, and the host computer of the terminal control system (1) sends a platform motion control instruction to control the ground mobile platform to move to the vicinity of the point to be measured; Step 2: the terminal control system (1) controls the movement of the hinge assembly, the telescopic assembly and the movable joint through the controller, so that the detection sensor (13) is accurately close to the point to be measured; Step 3: The projection of the geometric center of the top surface of the carrying platform on the ground is used as the reference coordinate origin O1, the positive direction of the x-axis is parallel to the length direction of the carrying platform and points to the laser radar (2), and the coordinate system is a right-handed coordinate system; Step 4, calculating the coordinates P1 of O1 through the controller, the laser radar (2), and the distance and direction information of the inertial sensor and odometer provided in the controller for controlling the movement of the carrying platform; Step 5: Taking the rotation axis center of the hinge assembly as the coordinate origin O2 of the movable joint, its coordinate P2 = P1 + P 机械安装位置 +P 水平推杆位置 ; Determine the M-DH coordinate parameter table through the structural parameters of each active joint and substitute it into the coordinate transformation matrix The description of the point in coordinate system i in coordinate system i-1 can be obtained, where the z-axis is defined as the direction of each rotation or movement axis, and the x-axis is the common perpendicular line of the two rotation axes, i.e., the connecting rod. In the formula: i represents the i-th joint, a i-1 For along x i-1 Direction z i-1 With z i The distance between i-1 For x i-1 Direction: z i-1 With z i Angle between i For along z i Direction x i-1 With x i The distance between i For z i Direction x i-1 With x i Angle between Then the coordinate transformation matrix between the plane center point Q of the detection sensor (13) and the coordinate origin O2 is: in [uvw] 3×3 is the attitude angle matrix of point Q, q 3×1 That is, the position vector of point Q; the terminal control system (1) collects and calculates the angle θ of each active joint i and the telescopic distance d of the telescopic assembly i ,pass The position of the center coordinate of the detection sensor (13) in space is determined by calculation as P=P2+q 3×1 ; Step six, setting RGB component values ​​and one-dimensional linear functions so that the one-dimensional data of the detection sensor (13) is mapped one-to-one with the RGB values, and the host computer of the terminal control system (1) draws a color point cloud map in real time in three-dimensional space based on the center coordinates P of the detection sensor (13) and the detection data of the detection sensor (13).

2. The multi-degree-of-freedom precise measurement device in a large-scale space according to claim 1, characterized in that: The carrying platform comprises an upper cover plate (3), the top surface of the upper cover plate (3) is slidably connected to a sliding support plate (5) via a slide rail (4), the top surface of the upper cover plate (3) is fixedly connected to a horizontal push rod (6), the output end of the horizontal push rod (6) is fixedly connected to the bottom surface of the sliding support plate (5) via a screw, the motor seat (7) of the horizontal push rod (6) is fixedly connected to the top surface of the upper cover plate (3), the hinge assembly is installed at one end of the top surface of the sliding support plate (5), and the terminal control system (1) is fixedly connected to one end of the upper cover plate (3) away from the sliding support plate (5).

3. The multi-degree-of-freedom precise measurement device in a large-scale space according to claim 2, characterized in that: The hinge assembly comprises a hinge base (8) fixedly connected to the top of the sliding support plate (5); the bottom end of the telescopic assembly is fixedly connected to a support frame (9); the bottom end of the support frame (9) is hinged to the top of the hinge base (8); the top of the sliding support plate (5) is hinged to an electric push rod (10); the output end of the electric push rod (10) is hinged to the middle of the support frame (9).

4. The multi-degree-of-freedom precise measurement device in a large-scale space according to claim 3, characterized in that: The telescopic assembly comprises a telescopic push rod (11), the support frame (9) is fixedly connected to the bottom end of the telescopic push rod (11), the top end of the telescopic push rod (11) is fixedly connected to a fixed plane (12), and the movable joint is installed on a side of the fixed plane (12) away from the telescopic push rod (11).

5. The multi-degree-of-freedom precise measurement device in a large-scale space according to claim 4, characterized in that: The movable joint comprises a first joint (16), a second joint (17) and a third joint (18), wherein the first joint (16) is fixedly connected to the fixed plane (12); a clamping bracket (14) is installed on the detection sensor (13), and the detection sensor (13) is fixedly connected to the third joint (18) through the clamping bracket (14); a lightweight bracket (19) is rotatably connected to the first joint (16) and the third joint (18), respectively; an end of the lightweight bracket (19) on the first joint (16) away from the first joint (16) is rotatably connected to the second joint (17), and an end of the lightweight bracket (19) on the third joint (18) away from the third joint (18) is fixedly connected to the second joint (17).

6. The large-scale space multi-degree-of-freedom precise measurement device according to claim 5, characterized in that: The first joint (16) comprises a first mounting frame (161) and a second mounting frame (162); the first mounting frame (161) and the second mounting frame (162) are respectively fixedly connected with a joint motor (163); the output end of the joint motor (163) on the first mounting frame (161) passes through the first mounting frame (161) and is transmission-connected with the second mounting frame (162); the joint motor (163) on the second mounting frame (162) passes through the second mounting frame (162) and is rotationally connected with the lightweight bracket (19); the second joint (17) and the third joint (18) have the same structure as the first joint (16); the clamping bracket (14) is fixedly connected to the first mounting frame (161) on the third joint (18).

7. The large-scale space multi-degree-of-freedom precise measurement device according to claim 1, characterized in that: The specific process of step 2 is as follows: in the process of approaching the plane to be measured, the distance sensor (15) is used to maintain the measuring distance and avoid collision; when the distance is less than 1 cm, the host computer software of the terminal control system (1) alarms; when the distance is detected to be less than 5 mm, the terminal control system (1) locks the terminal joint control command; after the host computer software unlocks the state, the terminal joint control command is restored; at the same time, a serial port camera is installed next to the distance sensor (15) and connected to the sub-controller to assist in observing the on-site detection situation; the relative position of the detection sensor (13) and the surface to be measured can be kept stable for a long time, avoiding the jitter and unstable measurement factors during manual operation.

8. The large-scale space multi-degree-of-freedom precise measurement device according to claim 1, characterized in that: The specific process of step 4 is as follows: when the controller is initialized, the laser radar (2) scans the distance and azimuth information of the closed space outline, the inertial sensor provided in the controller for controlling the movement of the carrying platform outputs the acceleration and angular velocity information of the carrying platform, and the odometer provided in the controller for controlling the movement of the carrying platform outputs the moving distance information of the carrying platform; a particle filtering method is used to update the trajectory state p(x 1:t |u 1:t-1 ,z 1:t ), use the trajectory status and lidar data to calculate and update the two-dimensional grid map data p(m|u 1:t ,z 1:t ), where u is control data, z is observation data, x is current state, and m is map data; the carrying platform can match the position and angle in the map according to the controller output data at the current moment.

9. The large-scale space multi-degree-of-freedom precise measurement device according to claim 1, characterized in that: The terminal control system (1) is designed with a center of gravity adjustment calculation module, which obtains the angle of each movable joint and calculates the overturning moment of the entire device according to the weight of each movable joint and the fulcrum position of the carrying platform. When the overturning moment is greater than or equal to a set overturning threshold, the carrying platform moves to ensure that the center of gravity projection is located within the front and rear side fulcrum interval of the carrying platform, thereby solving the overturning risk problem caused by insufficient counterweight and human operation.

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