Control method of mower and mower

Abstract

The invention provides a control method of a lawn mower and the lawn mower, and relates to the technical field of garden machinery, and the control method comprises the following steps: a current sampling step: obtaining the working current of a walking motor for driving the lawn mower to walk in real time at a preset sampling frequency; a change rate calculation step: calculating the instantaneous change rate of the working current based on the working current obtained in the current sampling period and the working current in at least one historical sampling period; a collision judgment step: judging whether the absolute value of the instantaneous change rate exceeds a preset collision judgment threshold value or not; and an obstacle avoidance response step: if the absolute value of the instantaneous change rate exceeds a collision judgment threshold value, judging that the hay mower is collided, and triggering an obstacle avoidance response program. By skillfully analyzing the dynamic change rate of the working current of the walking motor, the physical impact event of collision is converted into an electric signal characteristic which can be quickly and accurately identified, so that the inherent defects of the traditional mechanical and optical sensors are effectively overcome.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of garden machinery, in particular to a control method of a lawn mower and the lawn mower. BACKGROUND

[0002] With the development of the integration of smart home and garden machinery technology, automatic walking lawn mowers are widely used in the maintenance of family courtyards and small public green spaces due to their high efficiency and convenience. Such lawn mowers usually need to autonomously complete the mowing operation without human intervention, so the safety and reliability during operation are crucial. Precise detection and timely response to collision risks are one of the core technical requirements to ensure the safety of the equipment itself and avoid damage to surrounding obstacles. Currently, the collision detection function of automatic walking lawn mowers relies mainly on mechanical trigger sensors or optical ranging sensors to meet their operational needs in complex lawn environments.

[0003] However, the existing collision detection schemes still have obvious limitations in practical application. The scheme using mechanical trigger sensors can only trigger a collision signal through physical contact, which not only easily causes impact damage to the lawn mower body and the colliding object, but also easily causes detection delay or even missed detection when facing flexible obstacles or slight collisions. The scheme based on optical ranging sensors can achieve non-contact detection, but is greatly affected by environmental factors such as changes in light, grass shading, and rain and fog in the lawn area, and the detection accuracy is prone to fluctuation, making it difficult to ensure stability in complex working conditions. SUMMARY

[0004] The problem solved by the present application is: how to provide a lawn mower collision detection method that is more responsive, has stronger environmental interference resistance, and has higher reliability.

[0005] To solve the above problems, the present application provides a control method of a lawn mower and the lawn mower.

[0006] In a first aspect, the present application provides a control method of a lawn mower, the method comprising:

[0007] Current sampling step: acquiring the working current of a walking motor driving the lawn mower to walk in real time at a predetermined sampling frequency;

[0008] Change rate calculation step: calculating the instantaneous change rate of the working current based on the working current obtained in the current sampling period and the working current of at least one historical sampling period;

[0009] Collision judgment step: judging whether the absolute value of the instantaneous change rate exceeds a preset collision determination threshold;

[0010] Obstacle avoidance response step: if the absolute value of the instantaneous change rate exceeds the collision determination threshold, it is determined that the mower has collided, and an obstacle avoidance response program is triggered.

[0011] Optionally, before the current sampling step, the method further comprises

[0012] Reference current setting step: within a preset time period after the mower starts and enters a uniform walking state, the average working current of the motor is obtained, and the average working current is set as the reference working current of the mower on the current lawn.

[0013] Optionally, in the change rate calculation step, the specific way of calculating the instantaneous change rate is to use the first-order difference method or the average difference method based on the sliding window.

[0014] Optionally, the collision determination step further comprises:

[0015] Delay confirmation sub-step: when the absolute value of the instantaneous change rate is first detected to exceed the collision determination threshold, a preset delay timer is started; after the delay timer ends, the change rate calculation step is executed again, and if the absolute value of the calculated instantaneous change rate still exceeds the collision determination threshold, the collision is finally confirmed.

[0016] Optionally, the method further comprises:

[0017] Working condition verification step: in the current sampling step, the walking speed of the mower or the rotating speed of the walking motor is detected synchronously; only when the detected walking speed or rotating speed is within a preset stable working condition range, the subsequent change rate calculation step and collision determination step are executed.

[0018] Optionally, the obstacle avoidance response program comprises at least one of the following control instructions:

[0019] Control the mower to stop walking immediately;

[0020] Control the mower to stop walking first, and then move backward by a predetermined distance;

[0021] Control the mower to stop walking first, and then turn to a predetermined direction by a specific angle and then resume walking.

[0022] Optionally, the method further comprises:

[0023] Threshold self-adaptation step: according to the size of the reference working current, the value of the collision determination threshold is dynamically adjusted.

[0024] Optionally, in the threshold adaptation step, the larger the value of the reference operating current, the higher the collision determination threshold is set accordingly.

[0025] Optionally, the collision determination threshold can be manually set and adjusted by the user through the human-machine interface on the lawnmower or the accompanying mobile application.

[0026] In a second aspect, the present invention provides a lawnmower, the lawnmower comprising:

[0027] Organism;

[0028] A walking motor, mounted on the machine body, is used to drive the lawnmower to walk;

[0029] A current detection module is configured to detect the operating current of the walking motor in real time.

[0030] The control unit is housed within the machine body and is electrically connected to the walking motor and the current detection module;

[0031] The control unit is configured to execute the control method described above.

[0032] The beneficial effects of the lawnmower control method of this invention are as follows: When the lawnmower moves at a constant speed on flat grass, the load on the wheels driven by its motor is relatively stable, manifested as fluctuations in the operating current within a small range. Once the wheels collide with an obstacle (such as a stone or curb), the wheel's motion changes drastically—from rolling to an instantaneous stop or significant deceleration. According to the principles of motor dynamics, the instantaneous decrease in rotational speed leads to a reduction in back electromotive force, thereby triggering a sharp increase in winding current. This system captures the electrical signal characterization of this physical process through high-frequency current sampling. A collision is an instantaneous event, its electrical characteristic being a sharp pulse in the current over a very short time. By calculating the rate of change, the system can clearly distinguish this sudden collision event from gradual load changes caused by variations in ground slope and grass density. The system compares the calculated absolute value of the rate of change with a preset collision judgment threshold, which is much higher than the current fluctuation range during normal movement. Only when the rate of change exceeds this threshold is it considered an impact event severe enough to be classified as a collision. Once a collision is confirmed, the system immediately triggers the obstacle avoidance response procedure, thereby achieving a rapid response to the collision. Therefore, this invention cleverly analyzes the dynamic change rate of the walking motor's operating current, converting the physical impact event of a collision into an electrical signal feature that can be quickly and accurately identified. This effectively overcomes the inherent defects of traditional mechanical and optical sensors, providing a lawnmower collision detection solution that is faster, more reliable, more economical, and more adaptable. Attached Figure Description

[0033] Figure 1 This is a flowchart illustrating a control method according to an embodiment of the present invention;

[0034] Figure 2 This is a flowchart illustrating the reference current setting step and the operating condition verification step in an embodiment of the present invention.

[0035] Figure 3 This is a flowchart illustrating the rate of change calculation step and the collision judgment step in an embodiment of the present invention.

[0036] Figure 4 This is a flowchart illustrating the threshold adaptation step and obstacle avoidance response step in an embodiment of the present invention.

[0037] Figure 5 This is a structural block diagram of a lawnmower according to an embodiment of the present invention. Detailed Implementation

[0038] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Although some embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the present invention. It should be understood that the accompanying drawings and embodiments of the present invention are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0039] It should be understood that the various steps described in the method embodiments of the present invention may be performed in different orders and / or in parallel. Furthermore, the method embodiments may include additional steps and / or omit the steps shown. The scope of the present invention is not limited in this respect.

[0040] The term "comprising" and its variations as used herein are open-ended, meaning "including but not limited to"; the term "based on" means "at least partially based on"; the term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments"; and the term "optionally" means "optional embodiments". Definitions of other terms will be given in the following description. It should be noted that the concepts of "first," "second," etc., mentioned in this invention are used only to distinguish different devices, modules, or units, and are not intended to limit the order of functions performed by these devices, modules, or units or their interdependencies.

[0041] It should be noted that the terms "one" and "more" used in this invention are illustrative rather than restrictive. Those skilled in the art should understand that, unless otherwise expressly indicated in the context, they should be understood as "one or more".

[0042] The names of the messages or information exchanged between the multiple devices in the embodiments of the present invention are for illustrative purposes only and are not intended to limit the scope of these messages or information.

[0043] To address the problems existing in the background art, this embodiment provides a control method for a lawnmower, a lawnmower, and a storage medium.

[0044] like Figure 1 As shown in the figure, an embodiment of the present invention provides a control method for a lawnmower, comprising:

[0045] S100: Current sampling step: Obtain the operating current of the walking motor that drives the lawnmower in real time at a predetermined sampling frequency.

[0046] Specifically, this is the system's "sensing" stage. Through high-frequency (predetermined sampling frequency) real-time current monitoring, the system can capture subtle and rapid changes in current, providing a timely data foundation for subsequent analysis.

[0047] S200: Change rate calculation steps: Based on the operating current obtained in the current sampling period and the operating current in at least one historical sampling period, calculate the instantaneous change rate of the operating current.

[0048] Specifically, this is the system's "analysis" phase. It doesn't rely on the absolute magnitude of the current (because normal operating conditions such as uphill slopes or dense grass can also cause an increase in the absolute current value), but rather focuses on the rate of change of the current (instantaneous rate of change). A collision is a transient event, characterized by a sudden change in current within a very short time. By calculating the instantaneous rate of change, it's possible to effectively distinguish between the sudden current change caused by a collision and the gradual current change caused by normal load variations.

[0049] S300: Collision detection step: Determine whether the absolute value of the instantaneous rate of change exceeds a preset collision detection threshold.

[0050] Specifically, this is the system's "decision-making" stage. The system compares a calculated physical quantity (the absolute value of the instantaneous rate of change) with a pre-calibrated "collision judgment threshold" determined through experiments. This threshold sets the boundary between "normal load fluctuations" and "abnormal collision events." When the rate of change exceeds this threshold, a collision is considered to have occurred, requiring a response.

[0051] S400: Obstacle avoidance response steps: If the absolute value of the instantaneous rate of change exceeds the collision determination threshold, the lawnmower is determined to have collided, and the obstacle avoidance response procedure is triggered.

[0052] Specifically, this is the "execution" phase of the system. Once a collision is detected, the control system immediately switches from monitoring mode to action mode and executes the preset "obstacle avoidance response procedure," such as immediate stop, reverse movement, or turning, thereby preventing the equipment from jamming or being damaged.

[0053] In this embodiment, a current detection module connected to the drive circuit of the walking motor acquires the three-phase current or bus current of the walking motor in real time at a sampling frequency no less than a predetermined frequency as the operating current value. The control unit of the lawnmower calculates the instantaneous rate of change of the operating current based on the operating current value acquired in the current sampling period and the operating current values ​​of one or more previous historical sampling periods, using differential calculation or a sliding window linear regression algorithm. The control unit compares the absolute value of the calculated instantaneous rate of change with a preset collision judgment threshold; wherein, the collision judgment threshold is dynamically adjusted according to the basic load current of the lawnmower at different walking speed levels. If the absolute value of the instantaneous rate of change exceeds the collision judgment threshold, the control unit determines that the lawnmower has collided and immediately sends a control command to the walking drive circuit to trigger an obstacle avoidance response program; the obstacle avoidance response program includes, but is not limited to: controlling the lawnmower to immediately stop walking, moving in the opposite direction a predetermined distance, and / or performing a turning maneuver in place.

[0054] It should be noted that this embodiment uses the operating current of the walking motor as a "sensor" of the lawnmower's operating status (especially its external force state). When a lawnmower suddenly collides while in normal walking mode, its walking system will experience a huge reverse resistance or impact force. This external force will instantly increase the motor's load torque. For voltage-controlled motors, with the power supply voltage remaining basically constant, in order to overcome the suddenly increased load and attempt to maintain the preset speed, the motor will automatically draw a larger operating current from the power supply. Therefore, the collision event will be directly and quickly reflected as an instantaneous spike in the motor's operating current, effectively overcoming the inherent defects of traditional mechanical and optical sensors, and providing a lawnmower collision detection solution that is faster-responding, more reliable, more economical, and more adaptable.

[0055] Optionally, such as Figure 2 As shown, prior to the current sampling step, it also includes...

[0056] Reference current setting steps: During a preset time period after the lawnmower starts and enters a constant speed walking state, obtain the average operating current of the motor and set the average operating current as the reference operating current of the lawnmower on the current grass.

[0057] Specifically, after the lawnmower completes its startup procedure and the motor drive signal confirms that it has entered a uniform linear walking state for T1 seconds, the reference current sampling process is initiated. A preset time period is selected after the lawnmower starts and enters a uniform walking state to ensure that the lawnmower is in a stable, collision-free normal operating range. The current data collected during this period most accurately reflects the inherent resistance of the current grass. In the following T2 seconds, the operating current of the walking motor is continuously acquired at a predetermined sampling frequency and stored in a cyclic buffer. The arithmetic mean of all sampled operating currents within the T2 time period is calculated and set as the reference operating current for the current work cycle. By calculating the "average operating current" within this time period, the influence of instantaneous fluctuations is filtered out, resulting in a current value that stably represents the current basic load of the grass. This calculated "average operating current" is formally set as the "reference operating current," which will become the "new zero point" or reference baseline for subsequent collision detection algorithms. The collision judgment threshold used in the collision judgment step is determined based on the sum of the reference operating current and a preset offset.

[0058] In this optional embodiment, the lawnmower can automatically adjust its detection sensitivity in different yards, different areas, and even different times in the same yard (due to grass growth and humidity changes). Users do not need to perform any manual settings, achieving a "plug-and-play" intelligent experience and improving the product's versatility and user-friendliness. For manufacturers, there is no need to perform detailed threshold calibration for each machine at the end of the production line under simulated various grassy environments. A general algorithm is simply written, and the machine can automatically achieve optimal configuration at the user's site, reducing production costs. Furthermore, motor performance and transmission system resistance may slowly change with usage time, wear, and lubrication conditions. By recalibrating the reference current at the start of each task, the system can automatically offset the effects of this long-term drift, ensuring consistent detection performance throughout the product's lifecycle. Moreover, the rate of change meter is no longer based on the absolute change of the original current, but on the change relative to the reference current, making the system more attentive to abnormal sudden changes exceeding normal load: on dense grass (high base current), the system automatically sets a higher reference and corresponding threshold, thus avoiding misjudging current fluctuations caused by increased grass resistance during normal mowing as collisions. On sparse grass (low base current), the system sets a lower baseline and threshold to maintain high sensitivity to minor collisions (which may only cause a small change in absolute current), avoiding missed detections and thus significantly improving detection accuracy and greatly reducing false alarms and missed detection rates.

[0059] Optionally, such as Figure 3 As shown, in the steps of calculating the rate of change, the specific method for calculating the instantaneous rate of change is: using the first-order difference method or the average difference method based on the sliding window.

[0060] Specifically, the first-order difference method approximates the instantaneous rate of change using the difference between the current sample value and the previous sample value. It can capture the initial moment of a collision with minimal delay, achieving extremely fast response. This is particularly suitable for applications requiring immediate stopping after a collision where milliseconds are critical, minimizing impact damage. The sliding window average difference method, on the other hand, calculates the rate of change within a continuous, fixed-length "sliding window" (containing multiple historical sampling points) by linear fitting or calculating the average of continuous differences. This effectively smooths out noise interference that may arise from a single sampling point. For example, instantaneous fluctuations or electromagnetic interference in a motor drive circuit may cause an abnormal sampling value; using the first-order difference method might produce a false abrupt signal. The sliding window average difference method takes into account the overall trend within the window, greatly reducing the impact of a single noise point on the final calculation result. This improves the system's anti-interference capability and stability, and reduces the probability of false triggering. It is particularly suitable for scenarios with complex electrical environments or strict requirements on the false triggering rate. It can effectively prevent equipment from stopping unexpectedly due to interference and improve the user experience.

[0061] Optionally, such as Figure 3 As shown, the collision determination step also includes:

[0062] Delayed confirmation sub-step: When the absolute value of the instantaneous rate of change is detected to exceed the collision determination threshold for the first time, a preset delay timer is started; after the delay timer ends, the rate of change calculation step is executed again. If the absolute value of the calculated instantaneous rate of change still exceeds the collision determination threshold, then a collision is finally confirmed.

[0063] Specifically, when the absolute value of the instantaneous rate of change is detected to exceed the collision determination threshold for the first time, the obstacle avoidance response procedure is immediately suspended, and a delay timer of preset duration T_d is started simultaneously. Within one sampling cycle after the delay timer ends, the rate of change calculation step and the collision determination step are executed again, namely: acquiring a new operating current value; calculating a new instantaneous rate of change based on the new current value; and determining whether the absolute value of the new instantaneous rate of change still exceeds the collision determination threshold. If yes, a collision event is finally confirmed, and the obstacle avoidance response procedure is triggered. If no, the first exceedance of the threshold is determined to be an instantaneous disturbance, the delay timer is cleared, and the normal current sampling and monitoring loop is returned without triggering any obstacle avoidance action.

[0064] In this optional embodiment, the lawnmower operates in a complex environment. Motor commutation, momentary slippage of the drive wheels, cutting hard grass stems, and even internal electromagnetic interference can all cause instantaneous current spikes. This mechanism effectively filters out these brief, non-continuous interference pulses, preventing the lawnmower from frequently stopping or reversing due to "false collisions," thereby significantly improving the continuity of equipment operation and the smoothness of the user experience.

[0065] Optionally, such as Figure 2 As shown, the control methods for lawnmowers also include:

[0066] Operating condition verification steps: In the current sampling step, the travel speed of the lawnmower or the rotation speed of the walking motor is detected simultaneously; only when the detected travel speed or rotation speed is within the preset stable operating condition range, the subsequent rate of change calculation step and collision judgment step are executed.

[0067] Specifically, while the system samples the motor current in real time, it simultaneously detects a physical quantity that directly reflects the macroscopic motion state of the lawnmower: the actual speed of the lawnmower relative to the ground is obtained through GPS, odometer, or vision sensors; the speed is obtained through the encoder or Hall sensor built into the walking motor, which is proportional to the travel speed when there is no slippage. The monitored speed or speed is compared with a preset "stable operating range". This range is usually a narrow interval around the target speed (for example, if the target speed is 0.5 m / s, the stable range can be set to 0.45 to 0.55 m / s). If it is within the stable operating range, it indicates that the lawnmower is moving at a constant or near-constant speed. In this state, any drastic changes in the motor current (high instantaneous rate of change) are highly likely caused by abnormal events such as external collisions, rather than by its own acceleration / deceleration. Therefore, the system allows subsequent rate of change calculations and collision judgment steps to be executed normally. If it is outside the stable operating range: it indicates that the lawnmower is in a transient process such as acceleration, deceleration, turning, or starting / stopping. During these processes, the motor itself needs to generate enormous torque to change speed, which inevitably leads to drastic and normal changes in the operating current. If collision detection is activated at this time, it will generate continuous and catastrophic false alarms.

[0068] In this optional embodiment, the lawnmower frequently starts, stops, changes speed, and turns during operation. Without this step, each acceleration (sudden increase in current) and each deceleration (sudden decrease in current) would be misjudged by the system as a "collision" and a "reverse collision," causing the equipment to malfunction. This solution intelligently "shields" these known interference-causing transient processes through operational condition verification, fundamentally eliminating false triggers caused by its own acceleration and deceleration, greatly improving the user experience. Without operational condition verification, to avoid interference from acceleration and deceleration, the collision judgment threshold must be set very high, which leads to insensitivity to minor collisions (missed detections). In this embodiment, since the system has actively eliminated the most significant source of interference (its own speed changes), it can safely use a lower, more sensitive collision judgment threshold, thereby detecting more minor collisions and jams, further improving equipment safety. Moreover, this operational condition verification step is adaptive regardless of whether the lawnmower uses a fixed-speed cruise or a "stop-and-go" random path mode. It only cares about whether the current instantaneous state is stable, not about the preset target speed, thus having good universality.

[0069] Optionally, such as Figure 4 As shown, the obstacle avoidance response procedure includes at least one of the following control commands:

[0070] Control the lawnmower to stop immediately;

[0071] Control the lawnmower to stop moving first, and then move it backward a predetermined distance;

[0072] Control the lawnmower to first stop moving, then turn it in a predetermined direction at a specific angle before resuming movement.

[0073] Specifically, it offers a variety of response combinations (such as stop only, stop + reverse, stop + reverse + turn) to enable the lawnmower to adapt to different collision scenarios. Compared to a single stop action, the "reverse + turn" strategy can automatically extricate itself from a difficult situation and continue working, greatly reducing the number of times manual intervention is required, achieving a higher degree of automation, and improving the overall efficiency of lawnmowing operations.

[0074] Optionally, such as Figure 4 As shown, the control methods for lawnmowers also include:

[0075] Threshold adaptive step: Dynamically adjust the value of the collision determination threshold according to the magnitude of the reference operating current.

[0076] Specifically, when the lawnmower enters a dense, high-resistance lawn, the baseline workload increases significantly. At this time, the system automatically raises the collision detection threshold. This is because with a high base current, normal load fluctuations are also more pronounced; raising the threshold prevents these normal fluctuations from being misinterpreted as collisions. When the lawnmower enters a sparse, low-resistance lawn, the baseline workload decreases. At this time, the system automatically lowers the collision detection threshold. This is because with a low base current, even minor collisions can cause relatively significant current changes; lowering the threshold ensures sensitivity in detecting these minor collisions.

[0077] This optional embodiment addresses the inherent "one-size-fits-all" drawback of fixed threshold systems. By dynamically adjusting the threshold according to environmental load, the system ensures an optimal balance between "high sensitivity (preventing missed alarms)" and "high reliability (preventing false alarms)" under any lawn conditions, enabling the lawnmower to exhibit a consistent and excellent level of intelligence in any user's yard. The lawnmower is no longer a one-time factory calibration, but rather a continuous "online self-calibration" performed in different lawn areas during each task. This greatly improves the product's usability and ensures that the lawnmower can self-adjust and maintain optimal performance throughout its entire lifespan in the face of lawn changes (such as grass growth and wetness variations).

[0078] Optionally, such as Figure 4 As shown, in the threshold adaptation step, the larger the value of the reference operating current, the higher the collision determination threshold is set accordingly.

[0079] Specifically, the magnitude of the baseline operating current directly reflects the basic resistance of the lawn to the lawnmower's movement. The greater the resistance, the higher the average current required for the motor to maintain a constant speed. At high baseline current levels, the absolute amplitude of normal load fluctuations caused by the unevenness of the grass itself (such as clumps of grass and small puddles) will also be greater. To distinguish these larger normal fluctuations from genuine collision mutations, the collision detection threshold must be increased accordingly to ensure that the lawnmower does not frequently report false alarms under harsh operating conditions. Simultaneously, on sparse grass (low baseline operating current), the collision detection threshold should be decreased accordingly to maintain high sensitivity to minor collisions and avoid missed detections.

[0080] Optionally, the collision detection threshold can be manually set and adjusted by the user through the human-machine interface on the lawnmower or the accompanying mobile application.

[0081] Specifically, different users have different backyard environments and personal preferences. For example, users with exquisite gardens full of fragile decorations may want to set a lower threshold (higher sensitivity) to ensure that they react to even the slightest bumps and protect their property to the greatest extent. Users with wild, overgrown, and complex backyards can set a higher threshold (lower sensitivity) to reduce unnecessary downtime and allow the lawnmower to move more powerfully through complex areas. This gives users ultimate flexibility and control, meets personalized needs, and improves the product's user-friendliness and customer satisfaction.

[0082] This invention provides a lawnmower, comprising: a body 100; a walking motor 200 mounted on the body 100 for driving the lawnmower to move; a current detection module 300 configured to detect the operating current of the walking motor 200 in real time; and a control unit 400 disposed within the body 100 and electrically connected to the walking motor 200 and the current detection module 300; wherein the control unit 400 is configured to execute the aforementioned control method.

[0083] This invention provides a computer-readable storage medium storing a computer program thereon, which, when executed by a control unit, implements the control method described above.

[0084] While the present invention has been disclosed above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and all such changes and modifications will fall within the scope of protection of the present invention.

Claims

1. A control method for a lawnmower, characterized in that, The method includes: Current sampling step: The operating current of the walking motor that drives the lawnmower to walk is acquired in real time at a predetermined sampling frequency; Change rate calculation steps: Based on the operating current obtained in the current sampling period and the operating current in at least one historical sampling period, calculate the instantaneous change rate of the operating current; Collision determination step: Determine whether the absolute value of the instantaneous rate of change exceeds a preset collision determination threshold; Obstacle avoidance response steps: If the absolute value of the instantaneous rate of change exceeds the collision determination threshold, the lawnmower is determined to have collided, and the obstacle avoidance response procedure is triggered.

2. The control method according to claim 1, characterized in that, Prior to the current sampling step, it also includes Reference current setting steps: During a preset time period after the lawnmower starts and enters a constant speed walking state, the average operating current of the motor is obtained, and the average operating current is set as the reference operating current of the lawnmower on the current grass.

3. The control method according to claim 2, characterized in that, In the step of calculating the rate of change, the specific method for calculating the instantaneous rate of change is: using the first-order difference method or the average difference method based on a sliding window.

4. The control method according to claim 3, characterized in that, The collision determination step also includes: Delayed confirmation sub-step: When the absolute value of the instantaneous rate of change is detected to exceed the collision determination threshold for the first time, a preset delay timer is started; after the delay timer ends, the rate of change calculation step is executed again. If the absolute value of the calculated instantaneous rate of change still exceeds the collision determination threshold, then a collision is finally confirmed.

5. The control method according to claim 2, characterized in that, The method further includes: Operating condition verification steps: In the current sampling step, the travel speed of the lawnmower or the rotation speed of the walking motor is detected simultaneously; only when the detected travel speed or rotation speed is within the preset stable operating condition range, the subsequent rate of change calculation step and collision judgment step are executed.

6. The control method according to claim 2, characterized in that, The obstacle avoidance response procedure includes at least one of the following control commands: The lawnmower should be controlled to stop moving immediately; The lawnmower is controlled to first stop moving, and then move backward a predetermined distance; The lawnmower is controlled to first stop moving, then turn in a predetermined direction at a specific angle before resuming movement.

7. The control method according to any one of claims 2-6, characterized in that, The method further includes: Threshold adaptive step: Dynamically adjust the value of the collision determination threshold according to the magnitude of the reference operating current.

8. The control method according to claim 7, characterized in that, In the threshold adaptation step, the larger the value of the reference operating current, the higher the collision determination threshold is set accordingly.

9. The control method according to claim 8, characterized in that, The collision detection threshold can be manually set and adjusted by the user through the human-machine interface on the lawnmower or the accompanying mobile application.

10. A lawnmower, characterized in that, The lawnmower includes: Organism; A walking motor, mounted on the machine body, is used to drive the lawnmower to walk; A current detection module is configured to detect the operating current of the walking motor in real time. The control unit is housed within the machine body and is electrically connected to the walking motor and the current detection module; The control unit is configured to perform the control method as described in any one of claims 1 to 9.

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