Amphibious cross-domain multi-modal control system for unmanned platform

Abstract

The invention discloses a land and water cross-domain multi-mode control system for an unmanned platform, belongs to the technical field of unmanned platforms, and solves the problem that cooperative control of the unmanned platform in different modes is lacked in the prior art. The system comprises a remote control unit and an autonomous domain and is used for sending a control instruction to a receiving unit; the receiving unit is used for receiving the control instruction, the heartbeat signal and the state information, sending the control instruction and the state information to the state switching unit and sending the heartbeat signal to the monitoring unit; the state switching unit is used for sending the state information to the autonomous domain; in the remote control mode, the unmanned platform is remotely controlled; in the autonomous mode, whether working condition switching is carried out or not is judged according to the control instruction, if yes, working condition switching control is carried out, and if not, autonomous control corresponding to historical working conditions is carried out; the forwarding unit is used for forwarding the control instruction and the state information to the actuator and the autonomous domain respectively; the monitoring unit is used for monitoring the heartbeat signals and judging whether sudden stop is triggered or not. And cooperative control of the unmanned platform in different modes is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of unmanned platforms, and in particular to an unmanned platform cross-domain multi-modal control system for land and water. Background Art

[0002] With the development of unmanned technology, unmanned platforms can also have dual driving functions on land and water, and can complete functions such as underwater detection and offshore landing. Unmanned platforms can operate in autonomous mode or in manned remote control driving mode. According to the road conditions and vehicle control characteristics of the vehicle, four basic driving conditions are divided, namely land conditions, water conditions, water and land conditions, and manned remote control driving conditions. The first three conditions are all autonomous driving conditions. There are large differences in the control requirements for each actuator under each condition. How to achieve reasonable scheduling between the actuators according to the requirements is crucial for the stable operation of the unmanned platform in remote control and autonomous modes. How to coordinate control between manned remote control and unmanned autonomous mode, and how to coordinate control of different conditions under unmanned autonomous mode to ensure the driving safety of the unmanned platform have become urgent problems to be solved. Summary of the invention

[0003] In view of the above analysis, an embodiment of the present invention aims to provide an unmanned platform cross-domain multi-modal control system for land and water, so as to solve the problem of lack of collaborative control of unmanned platforms in different modes.

[0004] On the one hand, an embodiment of the present invention provides an unmanned platform cross-domain multi-modal control system, including the following modules:

[0005] A remote control unit, used for sending remote control instructions to a receiving unit;

[0006] An autonomous domain, used to send autonomous control instructions to a receiving unit;

[0007] A receiving unit, used to receive control instructions, a heartbeat signal of the actuator and status information, send the control instructions and status information to the state switching unit, and send the heartbeat signal of the actuator to the monitoring unit;

[0008] The state switching unit is used to send the state information to the autonomous domain through the forwarding unit; determine the current mode according to the control command; in the remote control mode, remotely control the unmanned platform through the forwarding unit; in the autonomous mode, determine whether to switch the working state according to the control command, if so, execute the working state switching control, otherwise perform the autonomous control corresponding to the historical working state;

[0009] a forwarding unit, used to forward control instructions to the actuator and forward status information to the autonomous domain;

[0010] The monitoring unit is used to monitor the heartbeat signal of the remote control unit, the receiving unit, the state switching unit, the forwarding unit and the actuator to determine whether an emergency stop is triggered.

[0011] Based on the further improvement of the above system, the unmanned platform actuator is remotely controlled, including:

[0012] When the historical working condition is the onshore working condition, if the shutter state is in the closed state, the shutter opening instruction is executed; if it is not in the closed state, the shutter automatic control instruction is executed;

[0013] When the historical working condition is not the onshore working condition, if the shutter state is in the open state, the shutter closing instruction is executed; if it is not in the open state, the shutter automatic control instruction is executed;

[0014] If the emergency stop is triggered, the emergency stop control is executed; if the emergency stop is not triggered, the control command is sent to the actuator through the forwarding unit.

[0015] Based on the further improvement of the above system, in remote control mode, emergency stop control is performed in the following way:

[0016] Determine whether the current brake pedal value is greater than 800 and the current gear is neutral. If so, release the emergency stop state; otherwise:

[0017] If the current working condition is on land or in water, the accelerator pedal position, brake pedal position and direction angle signal and the water maneuvering enable are all set to zero, and an emergency stop signal is fed back to the transmission module;

[0018] If the current working condition is on water, the brake pedal position, direction angle signal and water maneuvering enable are all set to zero; the water emergency switch is turned on and the gear position is set to zero; the accelerator pedal position is controlled in a step-by-step manner; and the emergency stop signal is fed back to the transmission module.

[0019] Based on the further improvement of the above system, the monitoring unit uses the following method to determine whether to trigger an emergency stop:

[0020] For each heartbeat signal, it is regularly determined whether the current heartbeat data is equal to the previous heartbeat data. If they are equal and the time difference between the current time and the time when the previous heartbeat data is received is greater than the first threshold, an emergency stop is triggered.

[0021] Based on the further improvement of the above system, the forwarding unit is also used to monitor the heartbeat signal of the remote control unit, the receiving unit, the state switching unit, the monitoring unit and the actuator to determine whether to trigger an emergency stop;

[0022] The forwarding unit determines whether to trigger an emergency stop in the following manner:

[0023] S11. For each heartbeat signal, periodically extract a group of heartbeat data; store the first data of the group of heartbeat data in the first position of the first judgment array, set the current position index to zero; and set the current traversal index to one;

[0024] S12, determine whether the data at the current traversal index in the group of heartbeat data is equal to the data at the current traversal index position in the first judgment array, if they are equal, execute step S13; if they are not equal, add one to the current position index, store the value at the current traversal index in the group of heartbeat data at the current position index of the first judgment array, and determine whether the current position index is equal to the preset threshold value, if so, execute step S14, otherwise execute step S13;

[0025] S13, the current traversal index is increased by one. If the current traversal index is equal to the length of the heartbeat data group, step S14 is executed; otherwise, step S12 is executed;

[0026] S14. If the current position index is less than the preset threshold, an emergency stop is triggered; otherwise, it is determined whether the numbers in the first judgment array are not equal to each other; if not, an emergency stop is triggered.

[0027] Based on the further improvement of the above system, the state switching unit performs the working condition switching control in the following manner:

[0028] Determine whether the current switching condition is met based on the working condition at the last moment and the switching target working condition. If not, trigger an emergency stop; otherwise, determine the current switching type based on the working condition at the last moment and the target working condition control;

[0029] Adjust the retractable and extended angles of the slide board according to the switching type;

[0030] Whether the switching is successful is determined based on the switching type. If successful, the autonomous control corresponding to the target working condition is executed; otherwise, the autonomous control corresponding to the historical working condition is executed.

[0031] Based on the further improvement of the above system, the retracting and extending angle of the slide plate is adjusted according to the switching type, including:

[0032] If the switching type is from the water-land working condition to the water working condition, the target angle of the water working condition is directly assigned to the bow upper slide, bow lower slide and tail slide;

[0033] If the switching type is from water-land condition to land condition, from land condition to water-land condition, or from water condition to water-land condition, then:

[0034] S21, judging whether the first upper slide plate has been adjusted to the target angle corresponding to the target working condition at the current moment, if so, the first step mark position is set to true, otherwise it is set to false; judging whether the first lower slide plate is retracted to the target angle corresponding to the target working condition at the current moment, if so, the second step mark position is set to true, otherwise it is set to false;

[0035] S22, if the flags of the first step and the second step are both false, the middle angle corresponding to the target working condition is assigned to the first upper slide, and the angle value fed back by the current sensor is continued to be assigned to the first lower slide, and the process returns to step S21, otherwise, step S23 is executed;

[0036] S23, if the first step flag is true and the second step flag is false, the first upper slide is assigned an intermediate angle corresponding to the target working condition, and the first lower slide is assigned a target angle corresponding to the target working condition, and the process returns to step S21, otherwise, the process goes to step S24;

[0037] S24, if the first step and the second step flag bits are both true, the first upper slide is assigned a target angle corresponding to the target working condition, the first lower slide is assigned a target angle corresponding to the target working condition, and the tail slide is assigned a target angle corresponding to the target working condition, otherwise an emergency stop is triggered.

[0038] Based on the further improvement of the above system, the following method is used to determine whether the switching is successful:

[0039] If the switching type is from land working condition to water-land working condition, from water working condition to water-land working condition, or from water-land working condition to water working condition, then determine whether the clutch is engaged, whether the shutter is closed, whether the vehicle posture adjustment state is in the suspension state, and whether the front upper slide, the front lower slide and the tail slide have all reached the target angle. If all are yes, the switching is successful, the current working condition is set as the target working condition, and the working condition switching flag is set to false, otherwise the working condition switching flag is set to true;

[0040] If the switching type is from water and land conditions to land conditions, determine whether the clutch is engaged, whether the vehicle posture adjustment state is in suspension state, and whether the front upper slide, front lower slide and tail slide have all reached the target angle. If all are yes, the switch is successful, the current condition is set to the target condition, and the condition switching flag is set to false, otherwise the condition switching flag is set to true.

[0041] Based on the further improvement of the above system, the state switching unit performs autonomous control corresponding to the above-water working condition in the following manner:

[0042] Determine whether the emergency stop is currently triggered. If so, execute the emergency stop control. Otherwise:

[0043] Set the parking command to not park; send actuator status information to the autonomous domain;

[0044] If the left and right water gate control instructions in the received control instructions are invalid, the left and right water gate actions are stopped; if the left and right water gate control instructions are open, the water maneuvering control enable is set to the enable mode, the water maneuvering control mode is set to the direct action mode, and the left and right water gates are opened; if the left and right water gate control instructions are closed, the left and right water gates are closed;

[0045] If the control skateboard angle in the received control command is enabled, the water maneuvering control mode is set to the target angle command mode, and the skateboard is controlled according to the skateboard angle value in the control command.

[0046] Based on the further improvement of the above system, the state switching unit adopts the following method to perform autonomous control corresponding to water and land working conditions:

[0047] Determine whether the emergency stop is currently triggered. If so, execute the emergency stop control. Otherwise:

[0048] Determine the desired engine speed according to the water mark in the control command;

[0049] If the expected speed is greater than 0, open the left and right water gates and set the clutch control mode to automatic; if both the land clutch and the water clutch are not engaged, set the gear to neutral, set the engine expected speed to idle, and set the parking command to park; if both the land clutch and the water clutch are engaged, set the gear to forward gear and set the parking command to no parking;

[0050] If the expected speed is less than 0, the left and right water gates are closed, the parking command is set to parking, the clutch control mode is set to manual mode, the land clutch and the water clutch are disconnected, and the gear is set to neutral;

[0051] If the desired speed is equal to 0, open the left and right water gates, set the accelerator pedal position to 0, set the parking command to parking, set the clutch control mode to manual mode, disconnect the land clutch and the water clutch, and set the gear to neutral;

[0052] controlling an accelerator pedal according to a calculated accelerator pedal position;

[0053] If the water mark position is on water, segmented steering control is performed according to the expected curvature on water; otherwise, segmented steering control is performed according to the expected curvature on land.

[0054] Compared with the prior art, the present invention obtains control instructions of the remote control unit and the autonomous domain, status information of each actuator in the chassis domain, and heartbeat signals through a receiving unit, and sends the control instructions and status information to the state switching unit, thereby feeding back the status information to the autonomous domain through the state switching unit, so as to facilitate accurate operation planning of the autonomous domain, and judge the current mode through the state switching unit. If it is a remote control mode, the unmanned platform is remotely controlled through the forwarding unit; if it is in the autonomous mode, judge whether to switch the working condition, if so, execute the working condition switching control, if not, execute the autonomous control under each working condition, so as to perform process control of the operation of the unmanned platform, ensure driving safety during the working condition switching process and in each working condition, in addition, by monitoring the heartbeat signals of each unit and each actuator of the unit, abnormalities are promptly discovered and emergency stops are triggered to ensure vehicle safety.

[0055] In the present invention, the above-mentioned technical solutions can also be combined with each other to achieve more preferred combination solutions. Other features and advantages of the present invention will be described in the subsequent description, and some advantages can become obvious from the description, or can be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained through the contents particularly pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] The accompanying drawings are only used for the purpose of illustrating specific embodiments and are not to be considered as limiting the present invention. In the entire drawings, the same reference symbols represent the same components;

[0057] Figure 1 It is a block diagram of a multi-modal control system for an unmanned platform across land and water according to an embodiment of the present invention;

[0058] Figure 2 This is a flow chart of emergency stop control according to an embodiment of the present invention. DETAILED DESCRIPTION

[0059] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not used to limit the scope of the present invention.

[0060] A specific embodiment of the present invention discloses a multi-modal control system for an unmanned platform across land and water, such as Figure 1 As shown, it includes the following modules:

[0061] A remote control unit, used for sending remote control instructions to a receiving unit;

[0062] An autonomous domain, used to send autonomous control instructions to a receiving unit;

[0063] A receiving unit, used to receive control instructions, a heartbeat signal of the actuator and status information, send the control instructions and status information to the state switching unit, and send the heartbeat signal of the actuator to the monitoring unit;

[0064] The state switching unit is used to send the state information to the autonomous domain through the forwarding unit; determine the current mode according to the control command; in the remote control mode, remotely control the unmanned platform through the forwarding unit; in the autonomous mode, determine whether to switch the working state according to the control command, if so, execute the working state switching control, otherwise perform the autonomous control corresponding to the historical working state;

[0065] a forwarding unit, used to forward control instructions to the actuator and forward status information to the autonomous domain;

[0066] The monitoring unit is used to monitor the heartbeat signal of the remote control unit, the receiving unit, the state switching unit and the actuator to determine whether to trigger an emergency stop. When implemented, the remote control unit includes a portable remote control and a short-range remote control.

[0067] It should be noted that the actuators of the unmanned platform that can cross land and water, namely the chassis actuators, include engines, gearboxes, left and right water gates, left and right rudders, suspension upgrades, front and rear slides, etc. The unmanned platform can be controlled by the autonomous domain to operate autonomously, or it can be controlled by the remote control unit to operate remotely. The control instructions received by the receiving unit include the control instructions issued by the autonomous domain and the control instructions issued by the remote control unit.

[0068] The autonomous domain is the autonomous planning module of the unmanned platform. The autonomous domain obtains environmental information through the sensor network, plans the driving strategy based on intelligent algorithms such as machine learning, reinforcement learning, and deep learning according to the mission objectives, status information, and environmental information of the unmanned platform, and sends control instructions to the control system to control the unmanned platform to run towards the planned target.

[0069] The control instructions sent by the autonomous domain include expected speed, expected curvature on land, expected curvature on water, expected acceleration, target working condition for working condition switching, historical working condition, water flag position, front upper slide angle, front lower slide angle, rear slide angle, left and right water gate control instructions (invalid, open, closed), control slide angle enable, etc. The control instructions sent by the remote control unit include control instructions for each actuator, such as shutter control instructions, front upper slide angle, and engine start / stop signals.

[0070] Compared with the prior art, the unmanned platform amphibious cross-domain multi-modal control system provided in this embodiment obtains the control instructions of the remote control unit and the autonomous domain, the status information of each actuator in the chassis domain, and the heartbeat signal through the receiving unit, and sends the control instructions and status information to the state switching unit, so that the status information is fed back to the autonomous domain through the state switching unit, so as to facilitate the accurate operation planning of the autonomous domain, and judge the current mode through the state switching unit. If it is the remote control mode, the unmanned platform is remotely controlled through the forwarding unit; if it is in the autonomous mode, it determines whether to switch the working condition, and if so, executes the working condition switching control, and if not, executes the autonomous control under each working condition, so as to perform process control on the operation of the unmanned platform and ensure driving safety during the working condition switching process and in each working condition. In addition, by monitoring the heartbeat signals of each unit and each actuator of the unit, abnormalities are promptly discovered and emergency stops are triggered to ensure vehicle safety.

[0071] During implementation, the receiving unit is used to obtain control instructions from the autonomous domain (the autonomous planning module of the unmanned platform) and the remote control unit, obtain the status information and heartbeat signal of the actuator from the chassis domain, and send the heartbeat signal to the monitoring unit for emergency stop monitoring, and send the control instructions and status information to the state switching unit for corresponding control processing.

[0072] Status information includes the position of the engine accelerator pedal, the angle of the skateboard, the vehicle posture adjustment status, the clutch status, the shutter status, etc. The heartbeat signal is used to monitor whether the actuator, remote control unit, state switching unit, and chassis actuators are operating normally. When the heartbeat signal determines that the operation is abnormal, an emergency stop will be triggered to protect the unmanned platform.

[0073] It should be noted that, under normal circumstances, the heartbeat signal of each actuator and each unit should start from 0 and increase by one each time it is executed until it exceeds a threshold, for example, exceeds 255, and then returns to 0, that is, the heartbeat signal is constantly changing.

[0074] Specifically, the monitoring unit determines whether to trigger an emergency stop in the following manner:

[0075] For each heartbeat signal, it is regularly determined whether the current heartbeat data is equal to the previous heartbeat data. If they are equal and the time difference between the current time and the time when the previous heartbeat data is received is greater than the first threshold, an emergency stop is triggered.

[0076] Since the heartbeat signal may jump repeatedly, the unmanned platform land-water cross-domain multi-modal control system of the present invention further includes a forwarding unit, which uses the second method to monitor the heartbeat signal of the remote control unit, the receiving unit, the state switching unit, the monitoring unit and the actuator to determine whether to trigger an emergency stop. The monitoring unit and the forwarding unit are redundant and complementary to each other, so as to more comprehensively and accurately determine the vehicle status and improve the operational reliability.

[0077] The receiving unit sends the heartbeat signal to the receiving unit and the monitoring unit for heartbeat signal monitoring to determine whether an emergency stop is triggered. The monitoring unit and the monitoring unit use two different methods for monitoring, so as to more accurately monitor the operating status of the actuator. At the same time, the forwarding unit and the monitoring unit also monitor the heartbeat signals of the remote control unit, the receiving unit, and the state switching unit. In addition, the forwarding unit and the monitoring unit monitor each other's heartbeat signals. That is, the forwarding unit monitors the heartbeat signals of each actuator, the remote control unit, the receiving unit, the state switching unit, and the monitoring unit to determine whether an emergency stop is triggered. If any heartbeat signal is abnormal, an emergency stop is triggered; the monitoring unit monitors the heartbeat signals of each actuator, the remote control unit, the receiving unit, the state switching unit, and the forwarding unit to determine whether an emergency stop is triggered. If any heartbeat signal is abnormal, an emergency stop is triggered.

[0078] Specifically, the forwarding unit determines whether to trigger an emergency stop in the following manner:

[0079] S11. For each heartbeat signal, periodically extract a group of heartbeat data; store the first data of the group of heartbeat data in the first position of the first judgment array, set the current position index to zero; and set the current traversal index to one;

[0080] S12, determine whether the data at the current traversal index in the group of heartbeat data is equal to the data at the current traversal index position in the first judgment array, if they are equal, execute step S13; if they are not equal, add one to the current position index, store the value at the current traversal index in the group of heartbeat data at the current position index of the first judgment array, and determine whether the current position index is equal to the preset threshold value, if so, execute step S14, otherwise execute step S13;

[0081] S13, the current traversal index is increased by one. If the current traversal index is equal to the length of the heartbeat data group, step S14 is executed; otherwise, step S12 is executed;

[0082] S14. If the current position index is less than the preset threshold, an emergency stop is triggered; otherwise, it is determined whether the numbers in the first judgment array are not equal to each other; if not, an emergency stop is triggered.

[0083] During implementation, for example, if the sampling period of the heartbeat signal is 100 milliseconds, the forwarding unit makes a judgment every 3 seconds, that is, it takes a set of heartbeat data Hb for each heartbeat signal every 3 seconds. i For example, among 30 heartbeat data, find out whether there are k unequal numbers, where k can be 3, so as to determine whether the heartbeat signal is abnormal.

[0084] First, the first judgment array is currently empty, and the current position index P index =0, current traversal index L index=1, the first data of the group of heartbeat data is stored in the first position of the first judgment array.

[0085] Determine heartbeat data Hb i The current traversal index L index The heartbeat data and the first judgment array current position index P index Are the heartbeat data at the same? If not, then L index +1, if the current traversal index is equal to the length of the heartbeat data group (that is, the heartbeat data Hb has not been traversed yet). i ), then continue to traverse the heartbeat data Hb i If the next data is not equal, P index +1, heartbeat data Hb i The current traversal index L index The heartbeat data is stored in the current position index P of the first judgment array index If the number of stored data in the first judgment array does not meet the requirement, then step S13 continues to search for the next unequal heartbeat signal. If the number requirement is met, then it is determined whether the numbers in the first judgment array are unequal. If not, an emergency stop is triggered. i If the number of items stored in the first judgment array still does not meet the requirements, it is considered that there is an abnormality and an emergency stop is triggered.

[0086] During implementation, the emergency stop flag can be used to indicate whether an emergency stop is triggered. If the emergency stop flag is true, it indicates that an emergency stop is triggered. If the emergency stop flag is false, it indicates that an emergency stop is not triggered. Initially, the default emergency stop flag is false. The monitoring unit and forwarding unit will set the emergency stop flag to true when determining that an emergency is triggered.

[0087] It should be noted that the instructions sent by the remote control unit to the receiving unit include emergency stop signals. When the receiving unit receives the emergency stop signal, it will also trigger an emergency stop and set the emergency stop flag to true. The receiving unit sends the received control instructions and status information to the state switching unit, and the state switching unit sends the status information to the autonomous domain through the forwarding unit; determines the current mode according to the control instructions; remotely controls the unmanned platform through the forwarding unit; in autonomous mode, determines whether to switch the working condition according to the control instructions, and if so, executes the working condition switching control, otherwise performs autonomous control corresponding to the historical working condition. The historical working condition is the latest recorded working condition, that is, the working condition executed by the unmanned platform at the last moment.

[0088] During implementation, the state switching unit first performs a heartbeat self-increment instruction, starting from 0 and increasing by 1 each time until the heartbeat exceeds 255 and then returns to zero. Then the received state information of each actuator is sent to the autonomous domain so that the autonomous domain can make the next step planning based on the state information. State information includes chassis speed, chassis curvature, left and right driving wheel speeds, front upper slide angle, front lower slide angle, rear slide angle, clutch control, gear position and other information.

[0089] During implementation, the state information is forwarded through the forwarding unit, so that the switching control and command forwarding are separated, thereby avoiding the situation where the state switching unit crashes and cannot send information.

[0090] Then, the control command is used to determine whether the current mode is the remote control mode or the autonomous mode. During implementation, the autonomous remote control mode switching command RASwitch from the portable remote controller is used to determine which mode to enter. If RASwitch = 1, the remote control mode is entered; if RASwitch = 2, the autonomous mode is entered.

[0091] In remote control mode, the unmanned platform actuator is remotely controlled, including:

[0092] When the historical working condition is the onshore working condition, if the shutter state is in the closed state, the shutter opening instruction is executed; if it is not in the closed state, the shutter automatic control instruction is executed;

[0093] When the historical working condition is not the onshore working condition, if the shutter state is in the open state, the shutter closing instruction is executed; if it is not in the open state, the shutter automatic control instruction is executed;

[0094] If the emergency stop is triggered, the emergency stop control is executed; if the emergency stop is not triggered, the control command is sent to the actuator through the forwarding unit.

[0095] If it is remote control mode, the shutter protection program is executed first. That is, if the historical working condition is onshore working condition, if the shutter state is closed, execute the shutter opening instruction, otherwise execute the shutter automatic control instruction; when the historical working condition is other working conditions, if the shutter state is open, execute the shutter closing instruction, otherwise execute the shutter automatic control instruction. Through the above program, the shutter can execute the corresponding instructions under different working conditions, thereby achieving the purpose of protecting the shutter. Executing the shutter opening / closing / automatic control instructions means sending these instructions to the chassis actuator through the forwarding module.

[0096] Then determine whether the emergency stop is triggered. If so, execute the emergency stop control.

[0097] Specifically, in remote control mode, such as Figure 2 As shown, emergency stop control is performed in the following way:

[0098] Determine whether the current brake pedal value is greater than 800 and the current gear is neutral. If so, release the emergency stop state; otherwise:

[0099] If the current working condition is on land or in water, the accelerator pedal position, brake pedal position and direction angle signal and the water maneuvering enable are all set to zero, and an emergency stop signal is fed back to the transmission module;

[0100] If the current working condition is on water, the brake pedal position, direction angle signal and water maneuvering enable are all set to zero; the water emergency switch is turned on and the gear position is set to zero; the accelerator pedal position is controlled in a step-by-step manner; and the emergency stop signal is fed back to the transmission module.

[0101] If the current brake pedal value is greater than 800 and the gear is in neutral, the vehicle is considered to have stopped and can be restarted. Therefore, the emergency stop can be released, that is, the emergency stop flag position is false. In the emergency stop state, only the remote control unit can release the emergency stop, thereby ensuring the safety of the unmanned platform.

[0102] During implementation, the accelerator pedal position is controlled in a step-by-step decreasing manner in the water working condition. If the current accelerator pedal position is greater than 800, the accelerator pedal position value is maintained at 800 for 2 seconds; if the current accelerator pedal position is between 500 and 800, the accelerator pedal position value is maintained at 500 for 3 seconds; in other cases, the accelerator pedal position is directly set to 0. The accelerator pedal position is gradually reduced until it reaches 0.

[0103] In remote control mode, if the emergency stop is not triggered, the normal command forwarding operation is performed, that is, the control command is forwarded to each actuator through the forwarding unit. For example, according to the blinds command of the portable remote control, the corresponding control command is sent to the blinds; according to the gear information of the remote control, the gear command is assigned a corresponding value and the gear command is sent to the actuator; the clutch, accelerator pedal position, brake pedal position, and direction angle signals are forwarded; the engine is controlled according to the engine start-stop signal, and when the engine start signal is received, the program-controlled start button is pressed and the engine is ignited; when the engine shutdown signal is received, the program-controlled start button is lifted and the engine shutdown command is executed; in other cases, the engine shutdown command is not executed and the program-controlled start button is lifted; the suspension control command of the remote control is received, if the suspension mode is manual, the suspension manual mode switch is turned on; if the suspension mode is automatic, the suspension manual mode switch is turned off; according to the remote control command, the suspension lifting, track tensioning, retraction and deployment of the front and rear slides, opening and closing of the left and right water gates, and opening and closing of the left and right rudders are issued.

[0104] In autonomous mode, before determining whether to switch the working condition, the shutter protection program is executed first. That is, if the historical working condition is the onshore working condition, if the shutter state is closed, the shutter opening instruction is executed, otherwise the shutter automatic control instruction is executed; when the historical working condition is other working conditions, if the shutter state is open, the shutter closing instruction is executed, otherwise the shutter automatic control instruction is executed.

[0105] Then determine whether the historical operating conditions and the target operating conditions are the same. If they are the same, there is no need to switch the operating conditions. If the historical operating conditions are on land conditions, the autonomous control corresponding to the onshore conditions is executed. If the historical operating conditions are on land and water conditions, the autonomous control corresponding to the onshore and water conditions is executed. If the historical operating conditions are on water conditions, the autonomous control corresponding to the on-water conditions is executed.

[0106] If the historical operating conditions are different from the target operating conditions, operating condition switching control needs to be performed.

[0107] Specifically, the state switching unit performs the operating mode switching control in the following manner:

[0108] Determine whether the current switching conditions are met based on historical operating conditions and target operating conditions. If not, trigger an emergency stop; otherwise, determine the current switching type based on historical operating conditions and target operating conditions;

[0109] Adjust the retractable and extended angles of the slide board according to the switching type;

[0110] Whether the switching is successful is determined based on the switching type. If successful, the autonomous control corresponding to the target working condition is executed; otherwise, the autonomous control corresponding to the historical working condition is executed.

[0111] During implementation, the working condition switching needs to meet one of the following rules: 1. The target working condition is on land, and the historical working condition is water-land working condition; 2. The target working condition is water working condition, and the historical working condition is water-land working condition; 3. The target working condition is water-land working condition, and the historical working condition is on land or water. If the switching rules are not met, an emergency stop is triggered.

[0112] The switching types obtained according to the historical operating conditions and the target operating conditions include switching from water-land operating conditions to water operating conditions, switching from water-land operating conditions to land operating conditions, switching from land operating conditions to water-land operating conditions, and switching from water operating conditions to water-land conditions.

[0113] Specifically, the retracting and extending angles of the slide plate are adjusted according to the switching type, including:

[0114] If the switching type is from the water-land working condition to the water working condition, the target angle of the water working condition is directly assigned to the bow upper slide, bow lower slide and tail slide;

[0115] If the switching type is from water-land condition to land condition, from land condition to water-land condition, or from water condition to water-land condition, then:

[0116] S21, judging whether the first upper slide plate has been adjusted to the target angle corresponding to the target working condition at the current moment, if so, the first step mark position is set to true, otherwise it is set to false; judging whether the first lower slide plate is retracted to the target angle corresponding to the target working condition at the current moment, if so, the second step mark position is set to true, otherwise it is set to false;

[0117] S22, if the flags of the first step and the second step are both false, the middle angle corresponding to the target working condition is assigned to the first upper slide, and the angle value fed back by the current sensor is continued to be assigned to the first lower slide, and the process returns to step S21, otherwise, step S23 is executed;

[0118] S23, if the first step flag is true and the second step flag is false, the first upper slide is assigned an intermediate angle corresponding to the target working condition, and the first lower slide is assigned a target angle corresponding to the target working condition, and the process returns to step S21, otherwise, the process goes to step S24;

[0119] S24, if the first step and the second step flag bits are both true, the first upper slide is assigned a target angle corresponding to the target working condition, the first lower slide is assigned a target angle corresponding to the target working condition, and the tail slide is assigned a target angle corresponding to the target working condition, otherwise an emergency stop is triggered.

[0120] When the water-land working condition is switched to the water working condition, the target angles of the water working condition can be directly assigned to the bow upper skateboard, bow lower skateboard and tail skateboard.

[0121] If the switching type is from water-land working condition to land working condition, from land working condition to water-land working condition, or from water working condition to water-land working condition, it is necessary to assign values ​​step by step.

[0122] During implementation, when the water-land working condition is switched to the land working condition, the target angle of the first upper skateboard is 33 degrees, the middle angle is 70 degrees, the target angle of the first lower skateboard is 27 degrees, and the target angle of the tail skateboard is 90 degrees. When the land working condition or the water working condition is switched to the water-land working condition, the target angle of the first upper skateboard is 180 degrees, the middle angle is 70 degrees, the target angle of the first lower skateboard is 22 degrees, and the target angle of the tail skateboard is 90 degrees.

[0123] After processing the slide plate retraction and extension angle, determine whether the switch is successful. Specifically include:

[0124] If the switching type is from land working condition to water-land working condition, from water working condition to water-land working condition, or from water-land working condition to water working condition, then determine whether the clutch is engaged, whether the shutter is closed, whether the vehicle posture adjustment state is in the suspension state, and whether the front upper slide, the front lower slide and the tail slide have all reached the target angle. If all are yes, the switching is successful, the current working condition is set as the target working condition, and the working condition switching flag is set to false, otherwise the working condition switching flag is set to true;

[0125] If the switching type is from water and land conditions to land conditions, determine whether the clutch is engaged, whether the vehicle posture adjustment state is in suspension state, and whether the front upper slide, front lower slide and tail slide have all reached the target angle. If all are yes, the switch is successful, the current condition is set to the target condition, and the condition switching flag is set to false, otherwise the condition switching flag is set to true.

[0126] If the switch is successful, the autonomous control corresponding to the target working condition is executed. Otherwise, the autonomous control corresponding to the historical working condition is executed.

[0127] If the target working condition is an overwater condition, autonomous control corresponding to the overwater condition is performed.

[0128] Specifically, the following methods are used to perform autonomous control corresponding to the above-water working conditions:

[0129] Determine whether the emergency stop is currently triggered. If so, execute the emergency stop control. Otherwise:

[0130] Set the parking command to not park; send actuator status information to the autonomous domain;

[0131] If the left and right water gate control instructions in the received control instructions are invalid, the left and right water gate actions are stopped; if the left and right water gate control instructions are open, the water maneuvering control enable is set to the enable mode, the water maneuvering control mode is set to the direct action mode, and the left and right water gates are opened; if the left and right water gate control instructions are closed, the left and right water gates are closed;

[0132] If the control skateboard angle in the received control command is enabled, the water maneuvering control mode is set to the target angle command mode, and the skateboard is controlled according to the skateboard angle value in the control command.

[0133] During autonomous control corresponding to the water working condition, it is first determined whether an emergency stop is triggered. If triggered, it is processed according to the aforementioned emergency stop control for the water working condition.

[0134] If the emergency stop is not triggered, the general control items are executed: the parking command is set to no parking, that is, a no parking command is sent to the actuator, and the actuator status information is fed back to the autonomous domain. During autonomous planning on water, the status information fed back to the autonomous domain includes: heading angle, expected heading angle, engine speed, front upper skateboard angle, tail skateboard angle, and left and right rudder angles. Among them, the expected heading angle is the expected curvature on the water sent from the autonomous domain. Then the left and right sluice gates are controlled according to the left and right sluice gate control instructions in the control instructions, and the skateboard angle is controlled according to the skateboard control instructions in the control instructions.

[0135] If the target operating condition is a land condition, autonomous control corresponding to the land condition is performed.

[0136] Specifically, autonomous control corresponding to onshore working conditions is performed in the following manner:

[0137] Determine whether the emergency stop is currently triggered. If so, execute the emergency stop control. Otherwise:

[0138] If the desired speed in the control command is 0, the parking command is set to the parking state, the gear is set to neutral, and the desired speed and the desired curvature on the water are both set to 0;

[0139] If the desired speed in the control command is greater than 0, the parking command is set to not park, if the land clutch is disengaged, the gear position is set to neutral, and the desired speed and curvature are set to 0; if the land clutch is engaged, the gear position is set to forward gear;

[0140] If the expected speed is less than 0, the parking command is set to no parking and the gear is set to reverse gear;

[0141] The parking command, gear position, desired speed, autonomous speed limit, desired curvature on land, and desired acceleration are sent to the chassis actuator.

[0142] During autonomous control corresponding to onshore working conditions, it is first determined whether an emergency stop is triggered. If triggered, the emergency stop control according to the above-mentioned onshore working conditions is performed.

[0143] If the emergency stop is not triggered, general control items are executed according to the expected speed: If the expected speed received from the autonomous domain is 0, it means that the current state is parking. The parking command is set to the parking state, the gear is set to neutral, and the expected speed and expected curvature fed back to the chassis actuator are set to 0.

[0144] If the expected speed is greater than 0, it means that the current state is the forward state on land, and the parking command is set to not park. If the clutch on land is disengaged, the gear position is set to neutral, and the expected speed and curvature fed back to the chassis are set to 0. If the clutch on land is engaged, the gear position is set to forward gear, and the expected speed, autonomous speed limit, expected curvature on land, and expected acceleration fed back to the chassis take the values ​​in the received control command.

[0145] If the expected speed is less than 0, it means that the current state is reverse on land. At this time, the parking command is set to no parking and the gear is set to reverse gear. The value conditions of the remaining feedback variables are consistent with the forward state on land, that is, the expected speed, autonomous speed limit, expected curvature on land and expected acceleration fed back to the chassis take the values ​​in the received control command.

[0146] The chassis operation is controlled by sending parking instructions, gear position, desired speed, autonomous speed limit, desired curvature on land, and desired acceleration to the chassis actuator.

[0147] If the target operating condition is a water or land condition, autonomous control corresponding to the water or land condition is performed.

[0148] Specifically, the following methods are used to perform autonomous control corresponding to water and land conditions:

[0149] Determine whether the emergency stop is currently triggered. If so, execute the emergency stop control. Otherwise:

[0150] Determine the desired engine speed according to the water mark in the control command;

[0151] If the expected speed is greater than 0, open the left and right water gates and set the clutch control mode to automatic; if both the land clutch and the water clutch are not engaged, set the gear to neutral, set the engine expected speed to idle, and set the parking command to park; if both the land clutch and the water clutch are engaged, set the gear to forward gear and set the parking command to no parking;

[0152] If the expected speed is less than 0, the left and right water gates are closed, the parking command is set to parking, the clutch control mode is set to manual mode, the land clutch and the water clutch are disconnected, and the gear is set to neutral;

[0153] If the desired speed is equal to 0, open the left and right water gates, set the accelerator pedal position to 0, set the parking command to parking, set the clutch control mode to manual mode, disconnect the land clutch and the water clutch, and set the gear to neutral;

[0154] controlling an accelerator pedal according to a calculated accelerator pedal position;

[0155] If the water mark position is on water, segmented steering control is performed according to the expected curvature on water; otherwise, segmented steering control is performed according to the expected curvature on land.

[0156] It should be noted that the idle speed is 800 rpm. The water flag is used to control whether to control according to the water coefficient or the land coefficient under water and land conditions. If the water flag sent by the autonomous domain is 1, the expected speed conversion coefficient adopts the water coefficient, and the expected engine speed is equal to the expected speed multiplied by the water conversion coefficient; otherwise, the land conversion coefficient is adopted, and the expected engine speed is equal to the expected speed multiplied by the land conversion coefficient.

[0157] The accelerator pedal is calculated in the following manner: the speed difference between the desired engine speed and the actual engine speed at the current moment is calculated;

[0158] If the speed difference is greater than or equal to 0, the current accelerator pedal position = the current speed difference × proportional coefficient + the last set accelerator pedal position;

[0159] If the speed difference is less than 0, the current accelerator pedal position = the last set accelerator pedal position - the current speed difference × the proportionality coefficient.

[0160] When implemented, the proportionality factor can be 0.01. If the calculated throttle pedal position is greater than 800, the throttle pedal position is set to 800 to prevent the throttle from suddenly opening fully. If the calculated throttle pedal position is less than 0, the throttle pedal position is set to 0 to prevent negative numbers.

[0161] Perform segmented steering control based on the desired curvature on the water, including:

[0162] When the expected curvature on the water is greater than 0.5, open the left water gate, open the right rudder, and close the left rudder;

[0163] When the expected curvature on the water is less than -0.5, open the right water gate, open the left rudder, and close the right rudder;

[0164] When the expected curvature on water is greater than or equal to 0.02 and less than or equal to 0.5, open the right rudder and close the left rudder;

[0165] When the expected curvature on water is greater than or equal to -0.5 and less than or equal to -0.02, open the left rudder and close the right rudder;

[0166] When the desired curvature on water is greater than -0.02 and less than 0.02, turn off the left and right rudders.

[0167] Step-by-step steering control based on the desired curvature on land, including:

[0168] The desired curvature on land is multiplied by the land coefficient to obtain the desired steering wheel angle;

[0169] When the value of the expected steering wheel angle is greater than or equal to 500 and less than or equal to 6000, or less than or equal to -500 and greater than or equal to -6000, the direction angle sent to the chassis actuator is the value of the expected steering wheel angle;

[0170] When the desired steering wheel angle is 0, the steering angle sent to the chassis actuator is 0;

[0171] When the expected steering wheel angle is greater than 0 and less than 500, the steering angle sent to the chassis actuator is 500; when the expected steering wheel angle is greater than -500 and less than 0, the steering angle sent to the chassis actuator is -500; when the expected steering wheel angle is greater than 6000 or less than -6000, the steering angle sent to the chassis actuator is 6000 or -6000.

[0172] It should be noted that the execution process of the state switching unit is in a while loop, that is, after executing the autonomous control corresponding to the water working condition, the autonomous control corresponding to the land working condition, or the autonomous control corresponding to the water and land working conditions, it returns to the starting position of the state switching unit, that is, the position where the heartbeat self-increment is executed.

[0173] It should be noted that the state information sent by the state switching unit to the autonomous domain and the instructions sent to the actuator are forwarded by the forwarding unit.

[0174] Those skilled in the art will appreciate that all or part of the processes of the above-mentioned embodiments can be implemented by instructing related hardware through a computer program, and the program can be stored in a computer-readable storage medium, wherein the computer-readable storage medium is a disk, an optical disk, a read-only storage memory, or a random access memory, etc.

[0175] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A multi-modal control system for unmanned platforms across land and water, characterized in that: Includes the following modules: A remote control unit, used for sending remote control instructions to a receiving unit; An autonomous domain, used to send autonomous control instructions to a receiving unit; A receiving unit, used to receive control instructions, a heartbeat signal of the actuator and status information, send the control instructions and status information to the state switching unit, and send the heartbeat signal of the actuator to the monitoring unit; The state switching unit is used to send the state information to the autonomous domain through the forwarding unit; determine the current mode according to the control command; in the remote control mode, remotely control the unmanned platform through the forwarding unit; in the autonomous mode, determine whether to switch the working state according to the control command, if so, execute the working state switching control, otherwise perform the autonomous control corresponding to the historical working state; a forwarding unit, used to forward control instructions to the actuator and forward status information to the autonomous domain; The monitoring unit is used to monitor the heartbeat signal of the remote control unit, the receiving unit, the state switching unit, the forwarding unit and the actuator to determine whether an emergency stop is triggered.

2. The unmanned platform land and water cross-domain multi-modal control system according to claim 1 is characterized in that: Remote control of unmanned platform actuators, including: When the historical working condition is the onshore working condition, if the shutter state is in the closed state, the shutter opening instruction is executed; if it is not in the closed state, the shutter automatic control instruction is executed; When the historical working condition is not the onshore working condition, if the shutter state is in the open state, the shutter closing instruction is executed; if it is not in the open state, the shutter automatic control instruction is executed; If the emergency stop is triggered, the emergency stop control is executed; if the emergency stop is not triggered, the control command is sent to the actuator through the forwarding unit.

3. The unmanned platform land and water cross-domain multi-modal control system according to claim 2 is characterized in that: In remote control mode, emergency stop control is performed in the following ways: Determine whether the current brake pedal value is greater than 800 and the current gear is neutral. If so, release the emergency stop state; otherwise: If the current working condition is on land or in water, the accelerator pedal position, brake pedal position and direction angle signal and the water maneuvering enable are all set to zero, and an emergency stop signal is fed back to the transmission module; If the current working condition is on water, the brake pedal position, direction angle signal and water maneuvering enable are all set to zero; the water emergency switch is turned on and the gear position is set to zero; the accelerator pedal position is controlled in a step-by-step manner; and the emergency stop signal is fed back to the transmission module.

4. The unmanned platform land and water cross-domain multi-modal control system according to claim 1 is characterized in that: The monitoring unit determines whether an emergency stop is triggered by: For each heartbeat signal, it is regularly determined whether the current heartbeat data is equal to the previous heartbeat data. If they are equal and the time difference between the current time and the time when the previous heartbeat data is received is greater than the first threshold, an emergency stop is triggered.

5. The unmanned platform land and water cross-domain multi-modal control system according to claim 1 is characterized in that: The forwarding unit is also used to monitor the heartbeat signal of the remote control unit, the receiving unit, the state switching unit, the monitoring unit and the actuator to determine whether to trigger an emergency stop; The forwarding unit determines whether to trigger an emergency stop in the following manner: S11. For each heartbeat signal, periodically extract a group of heartbeat data; store the first data of the group of heartbeat data in the first position of the first judgment array, and set the current position index to zero; Set the current traversal index to one; S12, judging whether the data at the current traversal index in the group of heartbeat data is equal to the data at the current traversal index position in the first judgment array, if they are equal, executing step S13; If they are not equal, the current position index is incremented by one, and the value at the current traversal index in the group of heartbeat data is stored at the current position index of the first judgment array, and it is determined whether the current position index is equal to the preset threshold value. If so, step S14 is executed, otherwise step S13 is executed; S13, the current traversal index is increased by one. If the current traversal index is equal to the length of the heartbeat data group, step S14 is executed; otherwise, step S12 is executed; S14. If the current position index is less than the preset threshold, an emergency stop is triggered; otherwise, it is determined whether the numbers in the first judgment array are not equal to each other; if not, an emergency stop is triggered.

6. The unmanned platform land and water cross-domain multi-modal control system according to claim 1 is characterized in that: The state switching unit performs the operating mode switching control in the following manner: Determine whether the current switching condition is met based on the working condition at the last moment and the switching target working condition. If not, trigger an emergency stop; otherwise, determine the current switching type based on the working condition at the last moment and the target working condition control; Adjust the retractable and extended angles of the slide board according to the switching type; Determine whether the switching is successful according to the switching type, and if successful, execute the autonomous control corresponding to the target working condition; Otherwise, autonomous control corresponding to historical operating conditions is executed.

7. The unmanned platform land and water cross-domain multi-modal control system according to claim 6 is characterized in that: Adjust the slide's retraction and extension angles according to the switching type, including: If the switching type is from the water-land working condition to the water working condition, the target angle of the water working condition is directly assigned to the bow upper slide, bow lower slide and tail slide; If the switching type is from water-land condition to land condition, from land condition to water-land condition, or from water condition to water-land condition, then: S21, judging whether the first upper slide plate has been adjusted to the target angle corresponding to the target working condition at the current moment, if so, the first step mark position is set to true, otherwise it is set to false; judging whether the first lower slide plate is retracted to the target angle corresponding to the target working condition at the current moment, if so, the second step mark position is set to true, otherwise it is set to false; S22, if the flags of the first step and the second step are both false, the middle angle corresponding to the target working condition is assigned to the first upper slide, and the angle value fed back by the current sensor is continued to be assigned to the first lower slide, and the process returns to step S21, otherwise, step S23 is executed; S23, if the first step flag is true and the second step flag is false, the first upper slide is assigned an intermediate angle corresponding to the target working condition, and the first lower slide is assigned a target angle corresponding to the target working condition, and the process returns to step S21, otherwise, the process goes to step S24; S24, if the first step and the second step flag bits are both true, the first upper slide is assigned a target angle corresponding to the target working condition, the first lower slide is assigned a target angle corresponding to the target working condition, and the tail slide is assigned a target angle corresponding to the target working condition, otherwise an emergency stop is triggered.

8. The unmanned platform land and water cross-domain multi-modal control system according to claim 6 is characterized in that: Use the following methods to determine whether the switch is successful: If the switching type is from land working condition to water-land working condition, from water working condition to water-land working condition, or from water-land working condition to water working condition, then judge whether the clutch is engaged, whether the shutter is closed, whether the vehicle posture adjustment state is in the suspension state, and whether the front upper slide, the front lower slide and the tail slide have all reached the target angle. If all are yes, the switching is successful, the current working condition is set as the target working condition, and the working condition switching flag is set to false, otherwise the working condition switching flag is set to true; If the switching type is from water and land conditions to land conditions, determine whether the clutch is engaged, whether the vehicle posture adjustment state is in suspension state, and whether the front upper slide, front lower slide and tail slide have all reached the target angle. If all are yes, the switch is successful, the current condition is set to the target condition, and the condition switching flag is set to false, otherwise the condition switching flag is set to true.

9. The unmanned platform land and water cross-domain multi-modal control system according to claim 1 is characterized in that: The state switching unit performs autonomous control corresponding to the above-water working conditions in the following manner: Determine whether the emergency stop is currently triggered. If so, execute the emergency stop control. Otherwise: Set the parking command to not park; send actuator status information to the autonomous domain; If the left and right water gate control instructions in the received control instructions are invalid, the left and right water gate actions are stopped; if the left and right water gate control instructions are open, the water maneuvering control enable is set to the enable mode, the water maneuvering control mode is set to the direct action mode, and the left and right water gates are opened; if the left and right water gate control instructions are closed, the left and right water gates are closed; If the control skateboard angle in the received control command is enabled, the water maneuvering control mode is set to the target angle command mode, and the skateboard is controlled according to the skateboard angle value in the control command.

10. The unmanned platform land and water cross-domain multi-modal control system according to claim 1 is characterized in that: The state switching unit performs autonomous control corresponding to water and land working conditions in the following manner: Determine whether the emergency stop is currently triggered. If so, execute the emergency stop control. Otherwise: Determine the desired engine speed according to the water mark in the control command; If the expected speed is greater than 0, open the left and right water gates and set the clutch control mode to automatic; if both the land clutch and the water clutch are not engaged, set the gear to neutral, set the engine expected speed to idle, and set the parking command to park; if both the land clutch and the water clutch are engaged, set the gear to forward gear and set the parking command to no parking; If the expected speed is less than 0, the left and right water gates are closed, the parking command is set to parking, the clutch control mode is set to manual mode, the land clutch and the water clutch are disconnected, and the gear is set to neutral; If the desired speed is equal to 0, open the left and right water gates, set the accelerator pedal position to 0, set the parking command to parking, set the clutch control mode to manual mode, disconnect the land clutch and the water clutch, and set the gear to neutral; controlling an accelerator pedal according to a calculated accelerator pedal position; If the water mark position is on water, segmented steering control is performed according to the expected curvature on water; otherwise, segmented steering control is performed according to the expected curvature on land.

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