RU2684419C1 - Double swing stand - Google Patents

Abstract

FIELD: measuring equipment.SUBSTANCE: invention relates to the field of measuring equipment, in particular to test equipment, and is intended for the certification and verification of inertial information converters (DLS, accelerometers, gyroscopic devices for various purposes), navigation systems (platform, freeware, etc.), stabilization and orientation, the control methods of which provide for sequential or simultaneous reversals for a given time along two axes at angles not exceeding ±360°. Two-axis rotary stand contains a base, a mounting platform fixed on a two-axis suspension, actuators and photoelectric angle sensors located along the axes of the internal and external suspension frame, power supply, control and monitoring unit. Additionally, two damping couplings are introduced; the drives used are worm-gear stepper motors. Drive of each axis is equipped with its own control controller, providing independent control. There are special platforms on the base, frames and platform that provide control of the orientation of the device under test. Bracket with an unloading device for fixing standard cables of the tested devices, the equivalent of the device under test, providing control of the turning accuracy, limit switches and stop mechanisms preventing the frames from turning more ±360° are also introduced.EFFECT: creation of a simple and reliable biaxial stand, designed to provide the required sequence of turns of the tested devices during the tests, with installation in the specified angular position on the angle of heel and pitch within ±360°.1 cl, 5 dwg

Description

The invention relates to the field of measuring equipment, mainly to testing equipment, and is intended for certification and verification of inertial information converters (DLS, accelerometers, gyroscopic devices for various purposes), navigation systems (platform, strap-on, etc.), stabilization and orientation, in methods control of which provides for sequential or simultaneous turns in a given time along two axes at angles not exceeding ± 360 °.

Known dynamic stand (Pat. No. 2526229 Russian Federation, IPC G01C 25/00, G01P 21/00. Dynamic stand / A.P. Shkadarevich, N.K. Gorbachenya, E.P. Vasenko, M.M. Tatur. - No. 2008152969/22; declared December 31, 08; published on September 10, 09, Bull. No. 25. - 7 pp.), Which has two axes of angular displacement and provides automatic turns of the device under test around its center of mass. The disadvantage of the stand is that there are no elements for the unambiguous orientation of the device under test, and for balancing the internal frame, it is necessary to move the cylindrical sectors on which the device being tested is installed, and the exhibition of its orientation is violated. Also, there is no possibility of dual control both from a PC and stand-alone - from the control and monitoring unit.

Known biaxial dynamic stand (Pat. 111634 Russian Federation, IPC G01C 25/00. Biaxial dynamic stand / EF Belov. - No. 20111131206/28; declared. 07.26.11; publ. 12.20.11, Bull. No. 35. - 6 p.), Which is intended for testing and calibration of measuring devices, angular velocity sensors, accelerometers, gyroscopic devices for various purposes and is selected as a prototype. The disadvantage of the stand is that it does not have the ability to bind the instrument coordinate system (SK) to the geographic and SK of the stand, the presence of a double control loop designed to strictly maintain a given angular velocity, and the presence of sliding current leads limits the power of the motors used in the drive, and imposes restrictions on the permissible currents transmitted to the axis.

The objective of the invention is to provide an inexpensive biaxial stand with a simpler and more reliable design. The biaxial stand is designed to provide the required sequence of turns of the tested devices during testing, with the platform installed in predetermined angular positions along the angle of heel and pitch within ± 360 °.

The technical result is achieved by the fact that in a biaxial rotary stand containing a base, an installation platform mounted on a biaxial suspension, drives and photoelectric angle sensors (DU) located along the axes of the inner and outer suspension frame, a power supply, control and monitoring unit (BPU), according to the invention, stepper motors (WD) with worm gears are used as drives; two damping couplings were introduced to interface the motor with the worm, the drive of each axis is equipped with a controller consisting of a digital processor module (MCP) and a switching module (MK); the first and second outputs of the remote control are connected respectively to the first and second inputs of the remote control port of the MCP; the first and second output of the DD port of the MCP are connected respectively to the first and second inputs of the MK, the outputs of the MK are connected to the corresponding inputs of the DD windings; BPU consists of a controller for receiving and transmitting information (PNI), a processor module (PM), a power supply unit, an emergency shutdown card for drives; in this case, the PM through the PNI controller is connected to the MCP interface modules of the respective drive controllers and to the PC, the PM control port is connected to the control input of the emergency shutdown board of the drives; the drive emergency shutdown board is configured to supply voltage from the power supply to the drive controllers MK; Introduced: limit switches and locking mechanisms of the inner and outer suspension frames, preventing them from turning more than ± 360 °, and the limit switches are connected to the emergency shutdown board of the drives; the equivalent of the device under test, providing control of the accuracy of the rotation of the rotary stand to a given angular position; on the base, frames and platform, plane-parallel platforms are made, providing control of the orientation of the device under test and binding to the geographical coordinate system.

Instead of sliding contacts, multicore cables were used to power and control the drive.

In FIG. 1 shows a functional diagram of a biaxial rotary stand.

During testing, the stand should ensure the installation of the device under test in the specified angular positions for a certain time. Along with the electromechanical part in the form of a rotary table, the stand includes a power supply, control and monitoring unit, which includes: power supplies, a processor module and a controller for receiving and transmitting information via the serial interface, an emergency shutdown card for drives, a display.

BPU carries out:

- management of the mode of operation of the stand;

- reception and processing of information from drives of internal and external frames via a serial data exchange interface, for example RS485, CAN, etc .;

- receiving and processing information from limit switches (reversal limiting mechanisms);

- display on the display, operating modes and status;

- connection to an external PC via a standard interface, for example RS485, CAN, etc .;

- the formation of voltages necessary for powering the boards included in the control unit and the drives of the internal and external frames;

- power off of drives in case of emergency (operation of limit switches or manual stop by the operator).

In FIG. 2 shows the electromechanical part of the stand - PS, containing the base 1, on which there are five screw supports with flywheels, three exhibition screw supports 2, providing the stand is displayed in a horizontal plane and two auxiliary screw supports 3 for fixing the exposed position. To move indoors, four wheels are placed on the bottom side of the base 4. Two racks 5 are mounted on the base with bearing bearings of the outer frame 6. On one rack (on the outer axis), drive 7 with drive controller 8 is installed, connectors for connecting to the power supply and control unit and the handwheel of the manual drive of the external frame 9. On the other rack (on the external axis) there is a discrete angle sensor - encoder 10. The latch (arrester) 12 of the external frame is also installed on the rack. The outer frame 6 is fixed in bearings pressed into racks; it provides turns of the tested device in pitch (around the axis OZ of the device) by ± 360 °. A limb of the outer frame 14 is mounted on the outer frame. The rotation of the inner frame 15 is provided by bearings pressed into the outer frame. The stand has locking mechanisms (11 and 13) and limit switches for the external and internal suspension frames, designed to prevent the frames from turning through an angle of more than ± 360 °. On the axis of the inner frame, on the one hand, there is a corresponding drive 16 with a controller 17, a handwheel of the manual drive 18 of the inner frame, and on the other hand, an encoder 19 and a latch 20 of the inner frame. Also on the outer side of the frame (on the encoder side) there are two platforms for securing a set of weights - counterweights 21, designed for static balancing of the internal frame with the installed device. The inner frame provides rotation of the device under test along the roll (around the axis OX of the device) by ± 360 °. A limb of the inner frame 22 is mounted on it. A platform 23 is rigidly attached to the inner frame 15, which is designed to install and secure the devices under test. Considering that the turns carried out by a biaxial rotary table do not exceed ± 360 ° when testing devices, a circuit solution was used that made it possible to dispense with a small number of communication lines between the control panel and the drives, which made it possible to pass them through the hollow axis of the frames. Due to this, the current leads traditionally used in multi-axis rotary tables are not used in the design. The use of current leads imposes a number of limitations: the high cost of high-quality current leads, an additional friction moment, restrictions on the minimum and maximum transmitted currents, restrictions on the transmitted frequencies, the probability of contact loss during vibration. To avoid twisting the cables of the device under test during testing, an arm 24 and a hollow shaft (frame axis) were introduced into the electromechanical part of the substation. A spring mechanism 25 is introduced into the bracket, preventing sagging of the device cables during turns. An angle sensor was chosen as an angular encoder, the design of which has a large diameter hole, for example, angular encoders of the RESR, REXM series from Renishaw, E series from Autonics and LIR series from SKB IS.

Landing surfaces and basing elements are made on the platform, providing an unambiguous orientation of the device relative to the axis of rotation of the stand, and there are plane-parallel platforms for setting the level (quadrant) at the stage of checking the error of the platform's rotation relative to the geographical coordinate system. Twenty four plane-parallel platforms 26 were made on the frames for setting the level at the stage of checking the exhibition of the rotary device relative to the geographical coordinate system, eight pieces on the inner frame and sixteen on the outer. The pads allow you to put the level on the selected pair and check the parallelism of the plane passing through them, corresponding to the axis of rotation. At the same time, the level can be set on the platform frames at the 0 ° position and when the frame is rotated 180 °. Based on four plane-parallel platforms 27 for the exhibition of substations in azimuth, they are strictly tied to the axis of rotation of the stand. Two platforms are made parallel to the Z axis, two other platforms are perpendicular to the Z axis. The exhibition in azimuth is carried out by pressing one or another pair of platforms to the stop element, oriented to the cardinal points using special tools.

The design of the substation includes mechanical (electromechanical) arresters, which ensure the installation of the external and internal frames in the initial position and prevent turns when fixing the device on the platform. To control the attachment of the instrument SK to the axis of rotation of the stand, as well as to check the orientation relative to the geographic SK, an additional device is introduced into the PS - the equivalent of the device in which the basic landing surfaces are similar to the landing surfaces of the device under test (set for the period of periodic, independent checks of the biaxial rotary table) .

To accurately maintain the angular position between the turns, a number of measures are provided: a self-braking worm gearbox (mechanical braking) is used in the drive and, if necessary, the stepper motor windings can be shorted by the power commutator (electrical braking). This technical solution made it possible to abandon the expensive ones that require additional power and create magnetic fields of electromagnetic couplings. In similar rotary tables with direct drive, the angular position is maintained by applying a control voltage to the engine that excludes rotor rotation. However, the direct drive control system, trying to maintain a predetermined angular position, carries out parasitic microoscillations of the rotor, which can be recorded by the device under test (determined by the passband). In addition, this leads to additional energy costs and heating of the motor windings. With a short-term “power failure”, this angular position may be lost. The combination of mechanical and electrical braking used in PS is effective in modes with long-term fixation of a given angular position.

The use of limiters with microswitches in the booth made it possible to prevent the turns of the external and internal frames by an angle of more than ± 360 °. U-turns are limited electronically and mechanically. The operation diagram of the limiter is shown in FIG. 3. On the fixed part of the stand, for example the rack of the external frame, the base 28 of the limiter is attached. On the base there is an axis 29, around which the V-shaped cam 30 rotates and the cam stop 31 is in the form of a protrusion, and two microswitches 32 are installed. Spring cam followers 33 are pressed onto the cam, pushing the microswitch button 34. On the moving side of the stand, for example, the frame, opposite The V-shaped cam is mounted with an abutment finger 35 in the form of a cylindrical rod, which allows the cam to be pushed when the frame rotates in the forward and reverse direction. Prevention of spontaneous movement of the cam is provided by a wave spring mounted on its axis. In the initial position (view a), the finger-rest is located between the shoulders of the V-shaped cam. At the beginning of the rotation of the frame in the forward direction, an emphasis finger pushes the cam shoulder, deflecting it to the side, according to view b. After the frame rotates 360 °, the finger-stop pushes the other cam shoulder until the spring pusher presses the microswitch button (view c). After the contacts of the microswitch are triggered, a signal is sent to stop the engine, which ensures rotation of the frame. If the electronic protection does not work, further movement of the cam and frame is blocked by the stop based on the limiter (type g). When the frame rotates in the opposite direction, similar actions occur.

Considering that devices with different versions of the execution of the basing elements can be tested, the equivalent of the device is made with the corresponding basing elements. An example of one embodiment of an equivalent device is shown in FIG. 4. In any design, a prism with strictly oriented surfaces (platforms) relative to each other should be present in its design. The sites 36 are parallel to the sites 37, the plane of the mirror 38, and perpendicular to the sites 39, 40, 41, 42 and the reference base surface of the device. Pads 39 are parallel to pads 40 and perpendicular to pads 36, 37, 42, 41, mirror plane 38. Pads 36, 37, 38, 39, 40, 42 are designed to set the level (quadrant) when checking the orientation of the SK stand and the device. Mirror 38 is designed to control the orientation of the coordinate system of the stand and the instrument using optical means (theodolites, collimator devices, gyrocompasses, etc.). The base pin and the landing diameter of the equivalent provide unambiguous orientation of the pads 39 and 40 parallel to the Y axis, and the pads 36 and 37 - the Z axis. The base surface provides a unique orientation of pads 41 and 42 perpendicular to the X axis. In addition, the installation of an optical quadrant on the pads ensures that the display is correct the angle measured by the angle sensor of the corresponding axis when installing in intermediate positions other than horizontal.

Two damping couplings are introduced to interface the stepper motor (WD) with the worm gear and to eliminate vibration during transmission of rotation from the work of the WD. The coupling is made in the form of two collet clamps mounted on mating shafts, and a damping insert made of rubber located between them, the profile and rigidity of which is selected to ensure the required damping coefficient. The combination of algorithms for smooth control of the operation of the motor stepper motor and the use of a damping clutch made it possible to significantly reduce vibration from resonances during rotation. Using the same drives along two axes allows you to have a universal structure of electronic blocks, the same control algorithms and software, which ensures interchangeability of blocks, reduces the range of elements used, simplifies setup and repair. With a significant difference in the moments of inertia of the internal and external frames, the coefficients in the controller memory change, and a new version of the software is not required.

The block diagram of the drive is shown in FIG. 5.

The drives of the roll and pitch turning mechanism are made in the form of two identical nodes, including:

- a worm gear driven by a motor drive;

- discrete angle sensor (angular encoder);

- controller;

- power electronic key board (switching module);

- serial interface module (interface module). Given that turning accuracy is mainly provided

drives with complex functional relationships, to explain their work, the structural diagram of the drives is presented in more detail.

Biaxial rotary stand works as follows. The drive is powered and controlled by the minimum number of conductors: 2 lines - power, 3 lines - control. Power supply to the control unit is carried out from a powerful uninterruptible power supply, which allows you to continue the test cycle when the mains voltage is disconnected and to prevent interference from entering the stand from the industrial network. Each drive is powered by one powerful stabilized power supply. The control unit manages the drives and exchanges information with them via a standard serial interface, for example, RS485, CAN, etc., which makes it possible to dispense with a small number of communication lines. The FWT processor module (PM) through the port (P _P Pi) associated with the port (ppm) controller PLI, and through the management port (P p _UE) served PM control commands to the control input (Vh.upr). emergency shutdown circuit boards An incremental type remote control generates impulses in proportion to the angle of rotation of the frame, and also gives an impulse when passing a special risk (zero mark), which is the origin. The signal from the first output (Output 1) of the remote control (zero mark) is fed to the first input (input 1) of the remote control port of the digital processor module (MCP). The signal from the second output (Output 2) of the remote control (pulses) is fed to the second input (input 2) of the remote control port of the MCP. The PPI controller through the second serial communication port ( _P2 ) is connected to the PC. Control signals (Cont.) Of the required angle of rotation and the reversal time with PPI controller through a first serial communication port (P _TAG1) formed by address supplied to the interface modules (roll or pitch) and transmitted to the SCM through the serial port (P _1). The MCP analyzes the control signals, compares them with the signal received from the remote control, and performs the following calculations: the current angular position, the required rotation angle, direction, the function of changing the rotation speed at each rotation point to provide a given time interval. According to the calculation results, the MCP sends a sequence of pulses to the first input (input 1) of the switching module through the first output (output 1) of the SD port, which determines the direction and speed of rotation. The motor windings are connected to the MK outputs (1, 2, ... n), where n is the number of motor windings. Through the output of the emergency shutdown board, the voltage (U _p ) of the output stage of the power electronic keys is supplied to the MK of the corresponding drive controllers. The MCP through the second output (output 2) of the SD port to the second input (input 2) of the MC generates a PWM signal proportional to the required supply voltage of the SD for a given speed. As a result, power electronic switches reduce the supply voltage to the desired value. According to the algorithm formed in the MCP, there is a smooth acceleration of the stepper motor due to an increase in the frequency of control pulses and smooth braking due to a decrease in the frequency when approaching a given angular position. A controller is programmed to control the U-turn.

The software allows you to implement any sequence diagram of the stand in positioning modes or angular velocities separately for each axis or simultaneously for two axes. The software is written to the non-volatile memory of the corresponding controller.

Thus, a biaxial rotary stand is declared, comprising a base, an installation platform mounted on a biaxial suspension, actuators and photoelectric angle sensors (DU) located along the axes of the inner and outer suspension frame, power supply, control and control unit (BPU). A distinctive feature of the stand is that stepper motors (WD) with worm gearboxes are used as drives; two damping couplings were introduced to interface the motor with the worm, the drive of each axis is equipped with a controller consisting of a digital processor module (MCP) and a switching module (MK); the first and second outputs of the remote control are connected respectively to the first and second inputs of the remote control port of the MCP; the first and second output of the DD port of the MCP are connected respectively to the first and second inputs of the MK, the outputs of the MK are connected to the corresponding inputs of the DD windings; A control unit consists of a controller for receiving and transmitting information (PPI), a processor module (PM), a power supply unit, and an emergency shutdown card for drives; in this case, the PM through the PPI controller is connected to the MCP interface modules of the respective drive controllers and PC, the PM control port is connected to the control input of the emergency shutdown board of the drives; the drive emergency shutdown board is configured to supply voltage from the power supply to the drive controllers MK; Introduced: limit switches and locking mechanisms of the inner and outer suspension frames, preventing them from turning more than ± 360 °, and the limit switches are connected to the emergency shutdown board of the drives; the equivalent of the device under test, providing control of the accuracy of the rotation of the rotary stand to a given angular position; on the base, frames and platform, plane-parallel platforms are made, providing control of the orientation of the device under test and binding to the geographical coordinate system.

In addition, a bracket with an unloading device was introduced to fix the standard cables of the tested devices.

Claims (2)

1. A biaxial rotary stand containing a base, an installation platform mounted on a biaxial suspension, drives and photoelectric angle sensors (DU) located along the axes of the inner and outer suspension frame, a power supply, control and monitoring unit (BCP), characterized in that as the drives used stepper motors (SH) with worm gears; two damping couplings were introduced to interface the motor with the worm, the drive of each axis is equipped with a controller consisting of a digital processor module (MCP) and a switching module (MK); the first and second outputs of the remote control are connected respectively to the first and second inputs of the remote control port of the MCP; the first and second output of the DD port of the MCP are connected respectively to the first and second inputs of the MK, the outputs of the MK are connected to the corresponding inputs of the DD windings; A control unit consists of a controller for receiving and transmitting information (PPI), a processor module (PM), a power supply unit, and an emergency shutdown card for drives; in this case, the PM through the PPI controller is connected to the MCP interface modules of the respective drive controllers and PC, the PM control port is connected to the control input of the emergency shutdown board of the drives; the drive emergency shutdown board is configured to supply voltage from the power supply to the drive controllers MK; Introduced: limit switches and locking mechanisms of the inner and outer suspension frames, preventing them from turning more than ± 360 °, and the limit switches are connected to the emergency shutdown board of the drives; the equivalent of the device under test, providing control of the accuracy of the rotation of the rotary stand to a given angular position; on the base, frames and platform, plane-parallel platforms are made, providing control of the orientation of the device under test and binding to the geographical coordinate system. 2. A biaxial rotary stand according to claim 1, characterized in that a bracket with an unloading device is introduced to secure the standard cables of the tested devices.

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