A stepping motor locking mechanism drive control system

Abstract

The present invention discloses a stepper motor locking mechanism drive control system, comprising: a repeated locking mechanism and a control drive system; wherein the control drive system comprises a stepper motor, a first limit switch, a second limit switch, a third limit switch, a fourth limit switch and a control drive unit; when the control drive unit collects the state of any one of the first limit switch and the second limit switch being triggered, it indicates that the repeated locking mechanism is locked in place; the third limit switch and the fourth limit switch are mutually redundant backups, and the third limit switch and the fourth limit switch are both connected to the repeated locking mechanism; when the control drive unit collects the state of any one of the third limit switch and the fourth limit switch being triggered, it indicates that the repeated locking mechanism is unlocked in place. The present invention ensures the stability of locking.

Description

Technical Field

[0001] The invention belongs to the technical field of locking mechanisms used in space, and in particular relates to a stepper motor locking mechanism drive control system. Background Art

[0002] With the continuous advancement of space exploration technology, the demand for locking, releasing, and unlocking payloads in the space-to-earth round-trip system is increasing. According to my country's aerospace construction plan, the space-to-earth round-trip transportation system is the next goal of my country's aerospace development. In this process, the demand for space payload transfer and transportation needs to be addressed. Among them, the reusable locking and release system is a key technology that urgently needs to be solved, especially the driving method, working principle, structural optimization, locking layout and system design of the locking mechanism drive system. At present, most reusable locking mechanisms require the driving motor to perform braking operations when they are in the locked state, and the stability of the locking cannot be guaranteed. Summary of the invention

[0003] The technical problem solved by the present invention is to overcome the deficiencies of the prior art and provide a stepper motor locking mechanism drive control system to ensure locking stability.

[0004] The object of the present invention is achieved through the following technical solutions: a stepper motor locking mechanism drive control system, comprising: a repeated locking mechanism and a control drive system; wherein the control drive system comprises a stepper motor, a first limit switch, a second limit switch, a third limit switch, a fourth limit switch and a control drive unit; the control drive unit is connected to the first limit switch, the second limit switch, the third limit switch and the fourth limit switch through a cable; the stepper motor is connected to the repeated locking mechanism; the first limit switch and the second limit switch are redundant backups for each other, and the first limit switch The first limit switch and the second limit switch are both connected to the repeated locking mechanism; if the control drive unit detects the triggering status of any one of the first limit switch and the second limit switch, it indicates that the repeated locking mechanism is locked in place; the third limit switch and the fourth limit switch are redundant backups of each other, and the third limit switch and the fourth limit switch are both connected to the repeated locking mechanism; if the control drive unit detects the triggering status of any one of the third limit switch and the fourth limit switch, it indicates that the repeated locking mechanism is unlocked in place.

[0005] In the above-mentioned stepper motor locking mechanism drive control system, the repeated locking mechanism includes a locking hook, a crank gear, a first stopper, a second stopper, a third stopper, a spring, a V-shaped crank connecting rod, a reducer and a locked hook shaft; wherein, the stepper motor is connected to the reducer; the output shaft of the reducer is connected to the crank gear, and the first stopper is installed on the crank gear; the central axis of the crank gear is connected to the V-shaped crank connecting rod; the third stopper is installed on the V-shaped crank connecting rod; one end of the locking hook is connected to the sliding guide rail of the V-shaped crank connecting rod; the middle part of the locking hook is connected to the fixed object through the spring, and the other end of the locking hook is connected to the locked hook shaft; the second stopper is arranged at the lower part of the locking hook shaft; the first stopper is connected to the first limit switch and the second limit switch; the second stopper is connected to the third limit switch and the fourth limit switch.

[0006] In the above-mentioned stepper motor locking mechanism drive control system, the control drive unit drives the stepper motor to move forward, and the stepper motor carries the crank gear to move through the reducer, while driving the V-shaped crank connecting rod to rotate forward, and at the same time drives the spring to stretch, and the locking hook slides upward; the locking hook drives the locked hook axis to move upward, and when the locking hook touches the second stop block, the third limit switch or the fourth limit switch is triggered, and the control drive unit collects the state of any one of the third limit switch and the fourth limit switch being triggered, indicating that the repeated locking mechanism is unlocked in place.

[0007] In the above-mentioned stepper motor locking mechanism drive control system, the control drive unit drives the stepper motor to move in the reverse direction, and the stepper motor carries the crank gear to move through the reducer, while driving the V-shaped crank connecting rod to rotate in the reverse direction, and at the same time drives the spring to lock, and the locking hook slides downward; the locking hook drives the locked hook axis to move downward, and when the first stop block touches the third stop block, the first limit switch or the second limit switch is triggered, and the control drive unit collects the state of any one of the first limit switch and the second limit switch being triggered, indicating that the repeated locking mechanism is locked in place.

[0008] In the above-mentioned stepper motor locking mechanism drive control system, the repeated locking mechanism needs to go through four stages during the movement process, namely, an acceleration stage, a high-speed stage, a deceleration stage and a low-speed stage.

[0009] In the above stepper motor locking mechanism drive control system, in the acceleration stage, the repeated locking mechanism is accelerated from the initial speed v0 to the acceleration a a Accelerate to maximum speed v v , the cumulative exercise time is Ta .

[0010] In the above stepper motor locking mechanism drive control system, in the high speed stage, the repeated locking mechanism is maintained at a maximum speed of v v The cumulative motion time is t1-T d -t0-T a ; Where t1 represents the moment when the repeated locking mechanism decelerates to v1, v1 represents the minimum speed, T d Indicates that the re-locking mechanism is composed of v v The time to decelerate to v1, t0 represents the moment when the repetitive locking mechanism starts to move, T a Indicates that the repeated locking mechanism is accelerated from v0 to v v time, v0 is the initial movement speed.

[0011] In the above stepper motor locking mechanism drive control system, in the deceleration stage, the repeated locking mechanism is driven by the maximum speed v v According to the deceleration-a a Accelerate to the minimum speed v1, the cumulative movement time is T d ; Among them, T d Indicates that the re-locking mechanism is composed of v v The time to decelerate to v1.

[0012] In the stepper motor locking mechanism drive control system, in the low speed stage, the repetitive locking mechanism keeps moving at the minimum speed v1 for t2-t1 time; wherein t1 represents the moment when the repetitive locking mechanism decelerates to v1, and t2 represents the moment when the repetitive locking mechanism finally stops moving.

[0013] In the above-mentioned stepper motor locking mechanism drive control system, the control drive unit can also provide 28V power supply voltage for the first limit switch, the second limit switch, the third limit switch and the fourth limit switch.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] (1) The present invention ensures the reliability of the locking mechanism when locking or unlocking by controlling the drive system;

[0016] (2) The present invention achieves a self-locking mode when the locking mechanism reaches the unlocking or locking position by combining a crank gear, a V-shaped crank connecting rod and a stopper. The stepper motor no longer needs to brake, which reduces power loss and improves system stability.

[0017] (3) The present invention adds a redundant limit switch to determine whether the locking mechanism is fully unlocked or fully locked, thereby ensuring the reliability of the system unlocking and locking. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0019] Figure 1 It is a principle block diagram of a stepper motor locking mechanism drive control system provided by an embodiment of the present invention;

[0020] Figure 2 is a schematic diagram of stepper motor motion planning provided by an embodiment of the present invention;

[0021] Figure 3 It is a diagram of the actual movement process of the tightening mechanism provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0022] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to be able to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that, in the absence of conflict, the embodiments of the present invention and the features described in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0023] Figure 1 1 is a principle block diagram of a stepper motor locking mechanism drive control system provided by an embodiment of the present invention. Figure 1 As shown, the stepper motor locking mechanism drive control system includes: a repeated locking mechanism and a control drive system; wherein,

[0024] The control drive system includes a stepper motor 1, a first limit switch 10, a second limit switch 11, a third limit switch 12, a fourth limit switch 13 and a control drive unit 14; the control drive unit 14 is connected to the first limit switch 10, the second limit switch 11, the third limit switch 12, and the fourth limit switch 13 through a cable; the stepper motor 1 is connected to the repeated locking mechanism.

[0025] The first limit switch 10 and the second limit switch 11 are redundant backups of each other, and both the first limit switch 10 and the second limit switch 11 are connected to the repeated locking mechanism; when the control drive unit 14 collects the triggering status of any one of the first limit switch 10 and the second limit switch 11, it indicates that the repeated locking mechanism is locked in place.

[0026] The third limit switch 12 and the fourth limit switch 13 are redundant backups for each other, and both the third limit switch 12 and the fourth limit switch 13 are connected to the repeated locking mechanism; when the control drive unit 14 collects the triggering status of any one of the third limit switch 12 and the fourth limit switch 13, it indicates that the repeated locking mechanism is unlocked in place.

[0027] like Figure 1 The repeated locking mechanism includes a locking hook 7, a crank gear 3, a first block 5, a second block 9, a third block 15, a spring 6, a V-shaped crank connecting rod 4, a reducer 2 and a locked hook shaft 8.

[0028] The stepper motor 1 is connected to the reducer 2; the output shaft of the reducer 2 is connected to the crank gear 3, and the first stopper 5 is installed on the crank gear 3; the central axis of the crank gear 3 is connected to the V-crank connecting rod 4; the third stopper 15 is installed on the V-crank connecting rod 4; one end of the lock hook 7 is connected to the sliding guide rail of the V-crank connecting rod 4; the middle part of the lock hook 7 is connected to the fixed object through the spring 6, and the other end of the lock hook 7 is connected to the locked hook shaft 8; the second stopper 9 is arranged at the lower part of the lock hook shaft 8, and the lock hook 7 releases the locked hook shaft 8 during the upward movement, and can touch the second stopper 9, thereby triggering the third limit switch 12 and the fourth limit switch 13 installed on the second stopper 9; the first stopper 5 is connected to the first limit switch 10 and the second limit switch 11; the second stopper 9 is connected to the third limit switch 12 and the fourth limit switch 13. The control drive unit 14 provides a 28V power supply voltage for the first limit switch 10 , the second limit switch 11 , the third limit switch 12 , and the fourth limit switch 13 .

[0029] Unlocking process: Control the drive unit 14 to drive the stepper motor 1 to move forward ( Figure 1 The stepper motor 1 moves with the crank gear 3 through the reducer 2, and at the same time drives the V-shaped crank connecting rod 4 to rotate forward, and at the same time drives the spring 6 to stretch, and the lock hook 7 slides upward; the lock hook 7 drives the locked hook shaft 8 to move upward, and when the other end of the lock hook 7 touches the second stopper 9, the third limit switch 12 or the fourth limit switch 13 is triggered, and the control drive unit 14 collects the state of any one of the third limit switch 12 and the fourth limit switch 13 being triggered, indicating that the repeated locking mechanism is unlocked in place.

[0030] Locking process: Control the drive unit 14 to drive the stepper motor 1 to reverse ( Figure 1The stepper motor 1 moves with the crank gear 3 through the reducer 2, and drives the V-shaped crank connecting rod 4 to rotate in the opposite direction, and drives the spring 6 to lock, and the lock hook 7 slides downward; the lock hook 7 drives the locked hook shaft 8 to move downward, and when the first stop block 5 touches the third stop block 15, the first limit switch 10 or the second limit switch 11 is triggered, and the control drive unit 14 collects the state of any one of the first limit switch 10 and the second limit switch 11 being triggered, indicating that the repeated locking mechanism is locked in place.

[0031] After receiving the locking or unlocking instruction of the locking mechanism, the control drive unit 14 is responsible for driving the stepper motor to realize movement during the movement of the locking mechanism according to the set motion planning algorithm (detailed description is shown below), and detects the status of the first limit switch 10, the second limit switch 11, the third limit switch 12, and the fourth limit switch 13 in real time.

[0032] During the planning process, the control drive unit makes the following definition: q(t) represents the current position of the locking mechanism, Indicates the speed of the locking mechanism movement, represents the acceleration of the locking mechanism, t0 represents the moment when the locking mechanism starts to move, t represents the time of the locking mechanism movement, T a Indicates that the locking mechanism accelerates from v0 to v v time, v v represents the maximum speed of the locking mechanism, v0 is the initial motion speed, v1 represents the minimum speed during the deceleration process of the locking mechanism, T d Indicates that the locking mechanism is composed of v v The time to decelerate to v1, h represents the position that the locking mechanism needs to move when unlocking or locking, n represents the position that the locking mechanism needs to move in the low-speed stage, t1 represents the moment when the locking mechanism decelerates to v1. t2 represents the moment when the locking mechanism finally stops moving. a Indicates the acceleration and deceleration of the locking mechanism.

[0033] The locking mechanism needs to go through four stages during the movement, such as Figure 2 As shown:

[0034] (1) Acceleration phase (t∈[t0 t0+T a ]), the locking mechanism is accelerated from the initial speed v0 to the acceleration a a Accelerate to maximum speed v v , the cumulative exercise time is T a .

[0035]

[0036] (2) High-speed stage (t∈[t0+T a t1-T d ]), the locking mechanism remains in high-speed motion, maintaining a maximum speed of v v The cumulative motion time is t1-T d -t0-T a .

[0037]

[0038] (3) Deceleration phase (t∈[t1-T d t1]), the locking mechanism is at the maximum speed v v According to the deceleration-a a Accelerate to the minimum speed v1, the cumulative movement time is T d .

[0039]

[0040] (4) Low-speed stage (t∈[t1 t2]): Keep moving at the minimum speed v1 for t2-t1 time.

[0041]

[0042] like Figure 3 As shown, when receiving the unlocking instruction of the locking mechanism, the motion control unit determines in real time whether the third limit switch 12 and the fourth limit switch 13 are triggered. If any of the third limit switch 12 and the fourth limit switch 13 is triggered, the low-speed motion stage is immediately entered, and the duration is maintained at t2-t1. Then the locking mechanism stop instruction is sent. If the third limit switch 12 and the fourth limit switch 13 are not triggered, the locking mechanism executes the unlocking instruction according to the set motion planning route and sends a stop instruction.

[0043] like Figure 3 As shown, when receiving the locking instruction of the locking mechanism, the motion control unit determines in real time whether the first limit switch 10 and the second limit switch 11 are triggered. If any of the first limit switch 10 and the second limit switch 11 is triggered, it immediately enters the low-speed motion stage, the duration is maintained at t2-t1, and then the locking mechanism stops. If the first limit switch 10 and the second limit switch 11 are not triggered, the locking mechanism executes the locking instruction according to the set motion planning route and sends a stop instruction after completing the locking instruction.

[0044] The control drive unit is used for motion planning and position control of the stepper motor, status acquisition of the limit switch, and fault judgment of the limit switch.

[0045] After receiving the locking task instruction from the locking mechanism, the control drive unit Figure 2The method shown in the figure is used for motion planning. After the motion planning is completed, the stepper motor is driven to move according to the planned instructions, and the stepper motor drives the reducer, the connecting rod and the lock hook to move; if the lock hook shaft touches the first limit switch and the second limit switch at time tx during the movement, the stepper motor will immediately decelerate to v v , and continue to exercise T e time, and then stop moving; if the locked hook shaft does not contact the first limit switch and the second limit switch during the movement, the stepper motor continues to move until the position command is executed (time t2), and then stops moving.

[0046] After receiving the unlocking task instruction of the locking mechanism, the control drive unit performs motion planning according to the position where the unlocking needs to move, such as Figure 3 As shown; after the motion planning is completed, the stepper motor is driven to move according to the planned instructions, and the stepper motor drives the reducer, the connecting rod and the lock hook to move; if the connecting rod is after the third limit switch and the fourth limit switch at time tx during the movement, the stepper motor will immediately decelerate to v v , and continue to exercise T e time, and then stop moving; if the connecting rod does not touch the third limit switch and the fourth limit switch during the movement, the stepper motor continues to move until the position command is executed (time t2), and then stops moving.

[0047] The present invention achieves a self-locking mode when the locking mechanism reaches the unlocking or locking position by combining a crank gear, a V-shaped crank connecting rod and a stopper, and the stepper motor does not need to brake anymore, thereby reducing power loss and improving the stability of the system; the present invention ensures the reliability of the locking mechanism when locking or unlocking by using a locking mechanism position determination method without a position sensor used in a control drive unit; the present invention avoids the phenomenon of loss of rotation after the stepper motor moves and a load is added by using a motion planning method in a control drive power supply, thereby improving the stability of the locking mechanism movement; the present invention determines whether the locking mechanism is unlocked or locked in place by adding a redundant limit switch, thereby ensuring the reliability of the system unlocking and locking; the present invention ensures that the locking mechanism can be unlocked or locked in place by using a determination method in which the limit switch and position are backed up during the movement of the locking mechanism, thereby improving the safety of the system.

[0048] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. A stepper motor locking mechanism drive control system, characterized in that include: Repeat locking mechanism and control drive system; wherein, The control drive system comprises a stepping motor (1), a first limit switch (10), a second limit switch (11), a third limit switch (12), a fourth limit switch (13) and a control drive unit (14); The control drive unit (14) is connected to the first limit switch (10), the second limit switch (11), the third limit switch (12), and the fourth limit switch (13) via cables; The stepping motor (1) is connected to the repeated locking mechanism; The first limit switch (10) and the second limit switch (11) are mutually redundant backups, and the first limit switch (10) and the second limit switch (11) are both connected to the repeated locking mechanism; when the control drive unit (14) detects the state of any one of the first limit switch (10) and the second limit switch (11) being triggered, it indicates that the repeated locking mechanism is locked in place; The third limit switch (12) and the fourth limit switch (13) are mutually redundant backups, and the third limit switch (12) and the fourth limit switch (13) are both connected to the repeated locking mechanism; when the control drive unit (14) detects the triggering state of any one of the third limit switch (12) and the fourth limit switch (13), it indicates that the repeated locking mechanism is unlocked in place; The repeated locking mechanism comprises a locking hook (7), a crank gear (3), a first stopper (5), a second stopper (9), a third stopper (15), a spring (6), a V-shaped crank connecting rod (4), a reducer (2) and a locked hook shaft (8); wherein: The stepping motor (1) is connected to the reducer (2); The output shaft of the reducer (2) is connected to the crank gear (3), and a first stopper (5) is installed on the crank gear (3); The central axis of the crank gear (3) is connected to the V-shaped crank connecting rod (4); a third stopper (15) is installed on the V-shaped crank connecting rod (4); One end of the locking hook (7) is connected to the sliding guide rail of the V-shaped crank connecting rod (4); the middle part of the locking hook (7) is connected to the fixed object through the spring (6), and the other end of the locking hook (7) is connected to the locked hook shaft (8); the second stopper (9) is arranged at the lower part of the locking hook shaft (8); The first stopper (5) is connected to the first limit switch (10) and the second limit switch (11); The second stopper (9) is connected to the third limit switch (12) and the fourth limit switch (13).

2. The stepper motor locking mechanism drive control system according to claim 1, characterized in that: The control drive unit (14) drives the stepper motor (1) to move forward, and the stepper motor (1) carries the crank gear (3) to move through the reducer (2), and at the same time drives the V-shaped crank connecting rod (4) to rotate forward, and at the same time drives the spring (6) to stretch, and the locking hook (7) slides upward; the locking hook (7) drives the locked hook shaft (8) to move upward, and when the locking hook (7) touches the second stopper (9), the third limit switch (12) or the fourth limit switch (13) is triggered, and the control drive unit (14) collects the state of any one of the third limit switch (12) and the fourth limit switch (13) being triggered, indicating that the repeated locking mechanism is unlocked in place.

3. The stepper motor locking mechanism drive control system according to claim 1, characterized in that: The control drive unit (14) drives the stepper motor (1) to move in the reverse direction. The stepper motor (1) carries the crank gear (3) to move through the reducer (2), and at the same time drives the V-shaped crank connecting rod (4) to rotate in the reverse direction, and at the same time drives the spring (6) to be locked, and the locking hook (7) slides downward; the locking hook (7) drives the locked hook shaft (8) to move downward, and when the first stop block (5) touches the third stop block (15), the first limit switch (10) or the second limit switch (11) is triggered, and the control drive unit (14) collects the state of any one of the first limit switch (10) and the second limit switch (11) being triggered, indicating that the repeated locking mechanism is locked in place.

4. The stepper motor locking mechanism drive control system according to claim 1, characterized in that: During the movement process, the repeated locking mechanism needs to go through four stages: acceleration stage, high speed stage, deceleration stage and low speed stage.

5. The stepper motor locking mechanism drive control system according to claim 4, characterized in that: In the acceleration stage, the re-locking mechanism increases from the initial speed v0 to the acceleration a a Accelerate to maximum speed v v , the cumulative exercise time is T a .

6. The stepper motor locking mechanism drive control system according to claim 4, characterized in that: In the high-speed stage, the repetitive locking mechanism maintains a maximum speed of v v The cumulative motion time is t1-T d -t0-T a ; Where t1 represents the moment when the repeated locking mechanism decelerates to v1, v1 represents the minimum speed, T d Indicates that the re-locking mechanism is composed of v v The time to decelerate to v1, t0 represents the moment when the repetitive locking mechanism starts to move, T a Indicates that the repeated locking mechanism is accelerated from v0 to v v time, v0 is the initial movement speed.

7. The stepper motor locking mechanism drive control system according to claim 4, characterized in that: During the deceleration phase, the re-locking mechanism is at a maximum speed v v According to the deceleration-a a Accelerate to the minimum speed v1, the cumulative movement time is T d ; Among them, T d Indicates that the re-locking mechanism is composed of v v The time to decelerate to v1.

8. The stepper motor locking mechanism drive control system according to claim 4, characterized in that: In the low-speed stage, the repetitive locking mechanism keeps moving at the minimum speed v1 for a time t2-t1; wherein t1 represents the moment when the repetitive locking mechanism decelerates to v1, and t2 represents the moment when the repetitive locking mechanism finally stops moving.

9. The stepper motor locking mechanism drive control system according to claim 1, characterized in that: The control drive unit (14) can also provide a 28V power supply voltage for the first limit switch (10), the second limit switch (11), the third limit switch (12) and the fourth limit switch (13).

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