Nondestructive fruit picking robot and control method thereof

Abstract

The invention relates to the technical field of agricultural intelligent equipment and robots, and provides a lossless fruit picking robot and a control method thereof.The lossless fruit picking robot comprises a picking execution mechanism, a moving walking mechanism, a bearing and positioning mechanism, an airflow generation and control mechanism and a dropped fruit bearing, conveying and collecting mechanism; the bottom of the bearing and positioning mechanism is arranged on the moving walking mechanism. The picking executing mechanism is arranged on the top of the bearing and positioning mechanism. A fruit stem is rapidly cut off through laser, obstacle removal, auxiliary separation and immediate fire suppression are achieved at the same time in the same operation area through PWM pulse high-pressure airflow generated by an electromagnetic valve, meanwhile, a non-contact lossless collection link is constructed in cooperation with a fruit receiving hopper, a flexible fruit guide pipe and a fruit collection box, and therefore rapid separation, damage controllability and operation safety are achieved; and a more feasible technical basis is provided for continuous and engineering automatic picking of an orchard scene.

Description

Technical Field

[0001] This invention relates to the field of agricultural intelligent equipment and robot technology, and in particular to a mobile fruit-picking robot and its picking execution mechanism and control system. It belongs to the cross-technical field of agricultural robots, mechatronics and intelligent picking equipment. Specifically, it relates to a non-destructive fruit-picking robot and its control method, and in particular to a non-contact non-destructive fruit-picking robot and its control method that combines laser cutting and pulsed air blowing. Background Technology

[0002] Fruit harvesting has long been one of the most labor-intensive, difficult-to-organize, and cost-sensitive stages in orchard production. On the one hand, harvesting is often concentrated within a short ripening window, resulting in significant seasonality and unpredictable labor demands. On the other hand, with changing population structures and rising labor costs, the economic viability of relying on manual labor for large-scale orchard harvesting continues to decline. Consequently, harvesting robots, utilizing robotic arms and mobile platforms, are gradually becoming a key technological direction for replacing manual labor, with the realistic expectation of improving operational efficiency, stabilizing fruit quality, and reducing overall labor costs. However, existing research and engineering practices generally point out that there are fundamental differences between natural orchard environments and factory-style settings: fruits are not arranged regularly, branches and leaves generally obstruct and dynamically change, the posture and spatial orientation of fruit stalks are highly discrete, and fruit size, weight, and maturity vary significantly. In this highly unstructured environment, harvesting operations must simultaneously meet three indicators: positioning and alignment capability, rapid separation capability, and damage control capability. However, these three are often strongly coupled and mutually restrictive: improving alignment accuracy requires more complex perception and slower motion strategies; improving separation speed often increases mechanical force or shortens action time, which exacerbates damage and failure; reducing damage requires more compliant and precise control, which slows down the cycle time and increases system complexity. This triple dilemma constitutes the core bottleneck for harvesting robots to move from the laboratory to industrial application, and it is also a key contradiction that existing technologies have been unable to completely resolve despite continuous iteration.

[0003] From the perspective of the fruit-plant separation mechanism, existing technologies can be broadly categorized into two main approaches for harvesting end effectors or harvesting schemes: one is to clamp the fruit and then detach the stem by pulling, rotating, or twisting; the other is to clamp or position the stem and then mechanically shear or cut it to achieve separation. The advantage of clamping and twisting schemes lies in their intuitive structure, simple action logic, and ease of integration into the end of a robotic arm, making them common in early commercialization solutions. However, they are essentially contact harvesting methods, and the fruit skin inevitably experiences normal compression and tangential friction during clamping. Furthermore, twisting / pulling introduces complex shear stress and bending moment at the connection between the fruit surface and the stem, easily leading to abrasions, indentations, or even skin damage, especially for soft fruits, thin-skinned fruits, and fruits with high maturity and reduced skin strength. To reduce damage, academia and industry have proposed numerous improvement approaches, such as using flexible materials to cover the grippers, designing underactuated compliant grippers, introducing current, active compliant control with force feedback, and reducing local stress concentration through shape adaptation, in an attempt to achieve a compromise between gripping stability and damage control. However, these improvements are more of a slow-release optimization of contact gripping and do not change the fundamental fact that contact and force must be applied to the fruit surface to complete separation. Therefore, under real working conditions such as the restriction of gripping posture due to branches and leaves, the instability of friction coefficient due to wet and slippery fruit surface, and the uncontrollable force distribution due to differences in fruit shape, problems such as slipping, crushing, or uncontrollable falling are still likely to occur, making it difficult to achieve both stability and zero damage at the same time.

[0004] In engineering applications, fruit stalk shearing / cutting end effectors are widely used. Their typical structure integrates a clamping mechanism and a shearing mechanism at the end of a robotic arm. A DC motor, cylinder, or electric actuator drives the moving blades / scissors to close, thus cutting the fruit stalk. Some solutions also incorporate vision sensors, photoelectric switches, or limit mechanisms to form a motion chain of alignment, clamping, shearing, and retraction. The core advantage of this type of solution lies in its clear cutting mechanism and definable separation action. Theoretically, it can reduce the pulling force on the fruit body caused by clamping and twisting, thereby improving fruit damage in some cases. Furthermore, the shearing action appears more controllable, facilitating programmed control through stroke and timing. However, in real-world orchard conditions, the shortcomings of this type of solution are equally prominent and structural: First, the shearing mechanism has very high requirements for the spatial position, posture, and alignment accuracy of the fruit stalk entering the shearing window. Obstruction by branches and leaves, skeletal deviation, or fruit covering the base of the stalk can make it difficult to expose the shearing point, easily leading to failures such as misalignment, jamming with branches and leaves, or inability to cut. Second, differences in the toughness, diameter, moisture content, and maturity of the fruit stalk fibers can cause significant fluctuations in the required shearing torque / thrust. Blade wear, sap contamination, gaps in the mechanism, and assembly errors can amplify these fluctuations, resulting in decreased cutting consistency and leading to repeated shearing and realignment, thus reducing the harvesting cycle. Third, the shearing action usually requires completing both a closed stroke and a reset stroke. When pursuing high-cycle continuous harvesting, this can easily create an efficiency ceiling. Furthermore, blades / scissors are typical consumable parts, and frequent maintenance and replacement can lead to downtime and increased costs. This demonstrates that traditional shearing methods struggle to balance efficiency and reliability under complex conditions.

[0005] Besides mechanical shearing, lasers, as a non-contact energy processing method, are gradually being introduced into agricultural and forestry operations, such as plant pruning and weeding. The basic principle is to use a high-power-density laser beam to rapidly heat the target tissue locally, causing it to carbonize, fracture, or lose structural strength, thereby achieving cutting or destruction. Compared to mechanical shears, lasers have potential advantages such as being non-contact, having a fast response time, adjustable energy, and theoretically reducing mechanical interference. Therefore, some publicly available solutions propose using lasers to replace garden shears for pruning branches and leaves, supplemented by a blowing structure to protect optical components, blow away debris, and cool or clean the work area to a certain extent. These explorations indicate that lasers have certain application prospects in agricultural and forestry scenarios, but the key to their engineering implementation lies not in whether they can cut, but in how to cut safely and stably in open-air flammable environments over a long period.

[0006] More specifically, the key engineering risks of laser applications in open-field agricultural and forestry environments are concentrated on thermal effects and ignition of combustibles: Combustible materials such as dead branches, fallen leaves, weeds, and dust are widely present in orchards, and new debris and fine fibers are generated during operations; the thermal effect of laser on fruit stalks or leaf tissues may produce sparks, smoldering fires, or localized continuous burning, which could ignite and spread further upon contact with dry combustibles, posing a safety hazard. Related project data also lists thermal and fire risks as key risks requiring attention and mitigation measures, indicating that in agricultural scenarios, simply pursuing laser cutting speed or power cannot directly translate into reliable productivity. Instead, the lack of a synchronous, rapid, and reliable fire suppression / extinguishing mechanism may limit its usability and scalability in continuous orchard operations. Therefore, for laser cutting technology to truly serve harvesting robots, it is necessary not only to solve the problem of energy application accuracy but also to address the issue of a safety closed loop synchronized with the laser processing process—that is, to provide timely and effective heat suppression and flame control capabilities within the same time window and spatial area where the cutting occurs.

[0007] On the other hand, orchard harvesting is not merely a single action of separating fruit from the plant, but a continuous process encompassing separation, fruit drop, receiving, buffering, transport, and collection. Uncertainty at any stage can negate the success and advantages of initial separation. In clamp-and-pick or shear-and-pick methods, the fruit is often directly held by the clamping mechanism and moved to the collection container. While this can control the fruit drop path to some extent, it still inevitably introduces contact compression and friction damage. In the free-fall method after cutting, the fruit falls uncontrollably due to changes in posture at the moment of cutting, interference from branches and leaves, and elastic rebound, making it prone to secondary collision damage. Furthermore, obstruction by branches and leaves can lead to unstable visual positioning, further amplifying the uncertainty of the drop at the moment of cutting. Some studies and reviews, when describing the harvesting of crops such as tomatoes, also mention combined methods such as suction cup adsorption, pulling, and then gripping and twisting by the hand to complete the harvest. This reflects the need for multiple methods to work together to improve the success rate under conditions of obstruction and limited space. However, multiple methods often also mean increased system complexity, potential failure points, and maintenance costs. Against this backdrop, the real need to improve post-harvest quality of fruit and achieve large-scale automated harvesting is to achieve controllable reception, effective buffering and guiding of fallen fruit, and stable introduction into collection containers without increasing strong contact with the fruit itself.

[0008] In summary, existing technologies mainly focus on two types of end effector systems: mechanical gripping and pulling, twisting and releasing, and mechanical shearing for cutting fruit stems. Based on these, various variants integrating vision / sensing with the actuators have been developed. On the one hand, existing harvesting robots mostly use mechanical grippers to hold the fruit and break the stem through pulling and rotating to complete the harvest. This process causes compression, abrasion, or tearing of the peel and pulp, leading to fruit damage, reduced marketability, and poor adaptability to different ripeness levels and varieties. On the other hand, existing stem-cutting solutions mostly use mechanical cutting / shearing mechanisms such as blades or scissors, which have problems such as high requirements for cutting stroke and alignment, low efficiency of repetitive actions, difficulty in precisely controlling cutting / shearing force, and difficulty in cutting the stem in one go when it is hard or in poor posture, affecting the harvesting success rate and work cycle. Furthermore, existing laser cutting applications in agricultural / forestry scenarios are prone to generating flames or spreading burns due to energy accumulation and localized overheating during long-term or continuous operation, posing safety hazards and failing to meet the needs of continuous and stable operation in complex orchard environments. However, these existing technologies still struggle to simultaneously resolve the following key challenges under the complex shading conditions of orchards:

[0009] Firstly, contact clamping is difficult to completely avoid fruit damage in engineering, and there is an inherent conflict between damage and gripping stability. Secondly, blades and scissors are sensitive to alignment, have limited cutting consistency and cycle time, and are prone to wear and tear, leading to maintenance costs and downtime risks. Thirdly, in obstructed environments, there is a lack of a means to clear obstacles / open the field of vision in a timely, rapid, and controllable manner to improve alignment and cutting success rates. Fourthly, while laser cutting has potential, it faces the risks of overheating and fire in open agricultural and forestry settings, and lacks a fire suppression safety mechanism that is synchronized with the cutting process, fast, and reliable. Fifthly, after cutting, fallen fruit still needs to be controlled and flexibly transported to reduce secondary collision damage and stably enter the box.

[0010] Based on the aforementioned background needs and pain points, there is an urgent need to design a non-destructive fruit picking robot to meet the actual needs of fruit picking. Summary of the Invention

[0011] To address the shortcomings of existing technologies, the purpose of this invention is to provide a non-destructive fruit-harvesting robot and its control method.

[0012] A non-destructive fruit-harvesting robot provided by the present invention includes: The mobile walking mechanism is used to support the entire machine and enable mobile operations in the orchard environment; The bearing and positioning mechanism is mounted on the bottom of the mobile walking mechanism; The harvesting mechanism is used to cut off the fruit stalk of the target fruit. It is positioned on top of the bearing and positioning mechanism and achieves its own spatial positioning and posture adjustment through the bearing and positioning mechanism. The airflow generation and control mechanism is configured on the mobile walking mechanism at one end and on the picking execution mechanism at the other end, and is used to output high-pressure pulsed airflow in a directional manner to the picking area; The fallen fruit receiving and conveying collection mechanism is configured at one end on the moving walking mechanism and at the other end on the picking execution mechanism. It is used to receive the cut fallen fruit and guide the fruit into the collection container.

[0013] Preferably, the harvesting mechanism includes at least a laser module and an end mount. The end mount is installed on the upper end of the bearing and positioning mechanism. The laser module is disposed on the end mount and is used to generate and output a laser beam. The laser output end of the laser module is arranged towards the cutting area of ​​the fruit stem.

[0014] Preferably, the bearing and positioning mechanism includes a robotic arm, the moving and walking mechanism includes a mobile chassis assembly, the mobile chassis assembly has a mounting platform, the lower end of the robotic arm is mounted on the mounting platform, and the upper end of the robotic arm is connected to an end mount.

[0015] Preferably, the airflow generation and control mechanism includes a controller, an air compressor, a solenoid valve, a gas pipeline, and an air blowing nozzle; The air nozzle is mounted on the end mount of the harvesting mechanism, the air compressor is mounted on the moving mechanism and is used to output high-pressure air, the output end of the air compressor is connected to one end of the gas pipeline, the air nozzle is mounted on the other end of the gas pipeline, and the solenoid valve is located on the gas pipeline. The solenoid valve is electrically connected to the controller, which can output a pulse width modulation control signal to the solenoid valve, so that the solenoid valve pulse modulates the gas in a high-frequency opening and closing manner, thereby forming a high-pressure pulsed airflow at the air blowing nozzle.

[0016] Preferably, the laser output end of the laser module of the harvesting execution mechanism is arranged facing the fruit stem cutting operation area, and the air blowing nozzle directs the spray direction towards the fruit stem cutting operation area, so that the airflow action area of ​​the air blowing nozzle and the laser beam action area overlap or intersect in space.

[0017] Preferably, the fallen fruit receiving and conveying collection mechanism includes at least a fruit receiving funnel, a flexible fruit guiding tube, and a fruit collection box; The fruit-receiving funnel is installed on the end mounting base of the harvesting execution mechanism. The opening of the fruit-receiving funnel is arranged facing the expected fruit drop area of ​​the target fruit. The funnel outlet of the fruit-receiving funnel is connected to one end of the flexible fruit guide tube, and the other end of the flexible fruit guide tube is connected to the fruit inlet of the fruit collection box.

[0018] Preferably, the mobile walking mechanism can adopt any of the following structural forms: Tracked walking structure; Wheeled walking structure; Quadrupedal locomotion structure.

[0019] Preferably, the gas pipeline of the bearing and positioning mechanism is fixed to the robotic arm via clamps, cable ties, sheaths, or internal wiring channels; The flexible fruit guide tube of the fallen fruit receiving and transporting collection mechanism is made of flexible material and is laid along the path from the robotic arm to the fruit collection box.

[0020] A non-destructive fruit harvesting control method provided by the present invention includes the following steps: End alignment step: Control the robotic arm to drive the picking mechanism to move to the vicinity of the target fruit and complete the posture adjustment so that the output direction of the laser module is aligned with the fruit stem cutting area, and at the same time, the inlet of the fruit receiving funnel is aligned with the expected fruit drop area of ​​the target fruit, thereby establishing consistency between the cutting point alignment and the fruit drop receiving alignment in space. Pulse air blowing preparation steps: Control the air compressor to establish air circuit pressure and control the solenoid valve to enter the controlled opening and closing state, so that the air blowing nozzle has the conditions to output high-pressure pulse airflow. Collaborative operation steps: While the laser module is cutting the fruit stem, or within a preset time window before and after the cutting, the solenoid valve is controlled to open and close according to the pulse width modulation signal, so that the air nozzle outputs high-pressure pulsed airflow to the fruit stem cutting area. Fallen fruit receiving and conveying steps: After the target fruit separates from the fruit stalk, it falls into the fruit receiving funnel and is then guided into the fruit collection box through the flexible fruit guide tube to complete the collection. End-of-line reset and next target step: Control the robotic arm to drive the picking mechanism away from the current working position and enter the alignment and picking cycle of the next target fruit, thereby achieving continuous picking.

[0021] Preferably, if a flame or abnormal burning signs appear during the laser burning process, the controller can immediately cut off the laser output and increase the duty cycle of the solenoid valve to 80% to 95% for 0.3 to 1.0 s to enhance the ability of the jet airflow to extinguish and suppress the flame, and then return to normal operating parameters or enter the next round of alignment.

[0022] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention is based on a harvesting end-effector technology that uses laser energy to quickly cut fruit stems, along with a matching pneumatic pulse airflow generation and jet control technology. The laser rapidly cuts the fruit stems, and a PWM pulse high-pressure airflow generated by a solenoid valve simultaneously clears obstacles, assists in separation, and provides immediate fire suppression within the same working area. Furthermore, it works in conjunction with a fruit-receiving funnel, a flexible fruit guide tube, and a fruit collection box to construct a non-contact, non-destructive collection link. This achieves rapid separation, controllable damage, and operational safety, eliminating the need for sacrifices between components. Instead, it achieves unity through system-level synergy between structure and control, providing a more feasible technical foundation for continuous and engineered automated harvesting in orchard settings.

[0023] 2. This invention utilizes a laser module for rapid severing of fruit stems, combined with a pneumatic system consisting of an air compressor, gas pipelines, solenoid valves, and air nozzles. The system employs pulse width modulation to drive the solenoid valves, generating high-pressure pulsed airflow. This airflow simultaneously achieves the following during harvesting: clearing obstructions such as branches and leaves around the target fruit to open the field of vision; providing pneumatic assistance for the separation of the stem from the fruit to promote contactless fruit drop; and extinguishing any sparks generated during laser cutting to suppress the fire source. This significantly improves harvesting efficiency and success rate while also enhancing operational safety. Simultaneously, this invention incorporates a fruit-receiving funnel to catch fallen fruit and a flexible guide tube to guide the fruit into a fruit collection box, establishing a non-destructive collection link for fruit reception and flexible transport. A robotic arm then enables spatial positioning and attitude adjustment of the harvesting mechanism, and a mobile chassis assembly facilitates mobile operations within the orchard. This allows for continuous, efficient, non-contact, low-damage, and safe harvesting tasks tailored to orchard scenarios. Compared to the common technical approach of existing harvesting robots that use mechanical grippers to hold the fruit and then break the fruit stem connection by pulling and rotating, or use blades and scissors to mechanically cut the fruit stem, this invention reconstructs the operation chain of efficient and non-destructive fruit separation, contactless fruit drop reception, guiding and conveying, and box collection from the system level. Its core technical means is to couple the rapid cutting capability of the laser module to the fruit stem with the PWM pulse high-pressure airflow formed by the air compressor, solenoid valve and air blowing nozzle, and further use the airflow simultaneously as a clearing, separation aid and an immediate fire suppression safety medium in laser operation scenarios. Finally, a buffer and conveying channel for the fallen fruit is constructed through the fruit receiving funnel, flexible fruit guide tube and fruit collection box. Because the modules mentioned above are arranged spatially around the same picking area and coordinated temporally around the same cutting process, this invention addresses multiple pain points in existing technologies, such as easy damage from contact picking, limited cutting efficiency and reliability, difficulty in alignment in obstructed environments, safety hazards from laser overheating, and uncontrollable fruit drop leading to secondary collisions. It forms a clear correspondence between technical means and technical effects, and demonstrates the synergistic effect between multiple means that existing technologies usually cannot disclose at the same time, thereby achieving a balance and unity between efficiency, non-destructiveness, and safety.

[0024] 3. In terms of reducing fruit damage, this invention primarily reduces mechanical contact with the fruit itself during the critical harvesting stage. Traditional gripper-type solutions require applying clamping force to the fruit surface, often necessitating significant normal pressure to ensure stable holding. However, fruits prone to indentation and crushing inevitably face a dilemma: insufficient clamping force leads to slippage and drop, while excessive force results in crushing and abrasion. Even with flexible materials or underactuated structures to alleviate stress concentration, it still relies on contact gripping, making it difficult to eliminate the risk of damage from compression and friction at its source. This invention shifts the separation target from the fruit itself to the fruit stem connection, using a laser module to quickly sever the stem. This eliminates the need for grippers to hold, pull, or twist the fruit, thus reducing compression, friction, and torque loading on the fruit surface during harvesting. This objectively lowers the probability of typical damage such as abrasions, crushing, and skin breakage, making it particularly suitable for harvesting fruits with thin skin, high maturity, or those sensitive to mechanical stress.

[0025] 4. This invention addresses the often overlooked but significantly impactful stage of fruit drop after cutting. By constructing a continuous receiving and guiding channel using a fruit-receiving funnel and a flexible fruit-guiding tube, it reduces secondary collision damage and improves the certainty of collection. Existing shearing methods, even if they can cut the fruit stalk, often result in sudden changes in posture or falling in unexpected directions at the moment of cutting, colliding with branches, the actuator, or the ground. Furthermore, under conditions of dense foliage, the fruit's fall path is even more uncontrollable, leading to frequent problems of successful cutting but failed entry into the collection box and fruit damage from impacts. This invention features a fruit-receiving funnel at the end, with its inlet aligned with the intended fruit drop area. After the fruit separates from the stalk, it falls into the funnel and immediately enters the flexible fruit-guiding tube. Within the flexible tube, gravity or a weak airflow provides buffering and guidance, ultimately leading to collection in the fruit collection box. Because the flexible fruit guide tube can absorb some of the impact and avoid secondary collisions caused by the free fall of the fruit, this structural link enables the separation result generated by the non-contact cutting handle to be stably converted into a non-destructive collection result into the box, thus making up for the shortcomings of existing technologies that only focus on cutting and ignore the damage caused by falling fruit at the system level.

[0026] 5. The efficiency improvements of this invention stem not only from the rapid response of laser cutting itself, but also from the comprehensive improvement of the working window, alignment difficulty, and number of repetitive actions achieved through pulsed airflow. Mechanical shears and blades typically require completing a closed-loop and reset stroke, and demand high precision in the posture and spatial alignment of the fruit stalk entering the cutting window. If there are obstructions such as branches and leaves, stalk misalignment, blade wear, or sap contamination, failures such as misalignment, entrapment of branches and leaves, or incomplete cutting are likely to occur, further triggering repeated alignment and cutting, leading to an increase in the average processing time per fruit. This invention achieves energy-based cutting of the fruit stalk using laser, independent of blade sharpness and mechanical closed-loop stroke. The execution rhythm of the cutting action is more easily improved and less prone to significant degradation due to mechanical wear. Meanwhile, the air nozzle outputs PWM pulse high-pressure airflow before, during, and after cutting, which can quickly separate obstructions around the fruit stem, creating a clearer operating space. This reduces the time consumed by repeated fine-tuning at the end of the robotic arm or waiting for the branches and leaves to rebound, and lowers the probability of rework caused by stem-finding failure due to obstructions or difficulty in exposing the cutting point. Thus, it demonstrates an efficiency advantage in the overall work cycle.

[0027] 6. The pulsed airflow of this invention not only clears obstacles but also provides non-contact separation assistance at the moment of fruit separation, thereby reducing secondary processing caused by residual fibers after cutting and fruit not falling off the branches. For some fruit stalks with strong fibers or unsatisfactory cutting angles, traditional shearing and pulling methods often result in fruit stalks not being completely severed or fruit still being hooked by branches and leaves, requiring re-clamping, re-cutting, or manual intervention, affecting continuous operation. This invention spatially overlaps or intersects the action area of ​​the pulsed airflow with the laser cutting area, causing the airflow to disturb the separation interface and exert short-term external force before and after cutting, promoting more thorough separation of the fruit and fruit stalk, cleaner fruit fall, and reducing the probability of residual fruit, thereby reducing repetitive actions and rework. This dual purpose of clearing obstacles and assisting separation is not a simple superposition but a spatiotemporal coupling around the same cutting process: the airflow is first used to open the field of vision and expose the cutting point, then works with the laser to complete the cutting and separation, and finally pushes the fruit into the receiving structure, realizing a continuous operation chain.

[0028] 7. The key to the safety of this invention lies in simultaneously using the compressed air pulse jet required for the operation as an immediate fire suppression medium for laser operation risks, constructing a safety technical solution with the same source pressure, same position injection, and same time window triggering. When lasers are used for cutting or pruning in orchards / woodlands or other environments with high combustible materials, the energy is highly concentrated in a small area, which can easily cause local overheating. Dead leaves, bark fibers of twigs, fruit stalk fibers, and attached dust may smolder, produce sparks, or even instantaneous flames under conditions of heat accumulation or spark splashing, thus bringing the risk of continuous combustion and spread. In contrast, the auxiliary air commonly used in existing solutions, such as constant flow from a fan or low-pressure continuous air blowing, is mainly used to blow away debris, reduce smoke and dust obstruction, and protect optical windows. Its airflow characteristics are usually nearly constant, with low peak momentum and weak instantaneous impact. Even with continuous blowing, if the outlet velocity and momentum are insufficient, it can often only disperse smoke and dust or slightly deflect the flame, making it difficult to achieve the instantaneous shear and cooling intensity required to extinguish the flame in the short time it takes for the flame to form. It may even fail to extinguish the flame quickly due to the flame being elongated and swaying. In other words, traditional constant-volume blowing is more geared towards clearing obstacles and purging, and is not inherently equivalent to fire suppression or extinguishing. This invention uses an air compressor as a unified pressure source, and modulates the gas flow through a solenoid valve using PWM pulse width modulation to form a high-peak, controllable frequency, and duty cycle pulsed high-pressure airflow. This pulse jet is characterized by high peak velocity, large instantaneous momentum, and fast rise time, enabling it to exert strong aerodynamic forces and heat exchange on potential fire points within the critical millisecond time window when a flame appears: on the one hand, the pulse jet generates greater instantaneous shear and disturbance at the flame root, causing the flame structure to break up and the flame surface to become unstable, thus making it easier to overcome the extinguishing conditions; on the other hand, the high-momentum airflow can quickly remove heat and dilute and replace local high-temperature air masses, lowering the surface temperature of combustibles and reducing the probability of smoldering turning into open flame; at the same time, the pulse jet has a stronger dispersing and stripping effect on sparks and embers, reducing the residence time of heat sources on the surface of combustibles and reducing the possibility of reignition. To achieve the aforementioned immediate fire suppression, this invention places air nozzles near the laser cutting area, achieving high spatial coupling between the airflow and the laser action zone, and synchronizing control with the laser operation process. During the critical stage of laser cutting the fruit stalk, the system immediately outputs high-pressure PWM pulsed airflow to instantly extinguish, cool, and suppress potential fire points, thereby reducing the risk of fire persistence and spread, and improving the safety margin and engineering applicability of laser stalk cutting under continuous orchard operation conditions. More importantly, this fire suppression capability does not rely on additional independent fire extinguishing subsystems, such as sprinklers, fire extinguishers, or independent fans. Instead, it reuses the same air path hardware to achieve a single air source with multiple uses, integrating functions such as obstacle clearing, assisting fruit drop, and fire suppression. This significantly improves safety while avoiding unnecessary structural complexity, volume, cost, and maintenance burden, demonstrating clear engineering and promotional value.

[0029] 8. In terms of reliability and maintainability, this invention reduces reliance on mechanical blades and high-friction moving parts, thus lowering the risk of performance degradation and downtime due to wear, jamming, and contamination. The cutting quality of traditional scissors and blade solutions is highly correlated with blade sharpness. Fruit stalk juice, dust, and fiber debris easily cause blade adhesion and wear, leading to a chain reaction of problems such as increased cutting force, higher shearing failure rate, and longer cycle times. Maintenance frequency and costs often increase rapidly with workload. The cutting mechanism of this invention is dominated by laser energy, and airflow can reduce residue accumulation and obstruction in the cutting area to a certain extent, thereby reducing sensitivity to blade sharpness and mechanical clearance. Simultaneously, the PWM control of the solenoid valve allows for parameterized adjustment of the pulse airflow frequency and duty cycle. Software calibration can adapt to different fruit stalk strengths, obstruction levels, and working distances without frequent replacement of mechanical structures or adjustment of complex mechanism strokes. This hardware universality and parameter adjustment approach makes the system more adaptable to complex working conditions and facilitates subsequent iterative optimization and large-scale maintenance management.

[0030] 9. In terms of adaptability and versatility, this invention focuses on the fruit stalk as the key point of action and adapts to changes in fruit size through a receiving and flexible conveying link. Therefore, compared to gripper-type solutions, it is easier to cover the harvesting needs of multiple varieties and ripeness levels of fruits. Gripper-type solutions often require changing the gripper contour, adjusting the gripping strategy, or recalibrating the force control parameters for different fruit shapes; otherwise, unstable grip or increased damage may occur. In contrast, the separation action of this invention does not rely on the gripping of the fruit itself. The differences in fruit size are mainly accommodated by the inlet of the fruit receiving funnel and the inner diameter range of the flexible fruit guide tube, making the system structure more conducive to forming a universal platform. At the same time, the combination of airflow pulse and laser cutting also improves the adaptability to fluctuations in fruit stalk strength and posture differences. In cases of heavier obstruction or tougher fruit stalks, the frequency, duty cycle, and pressure of the pulsed airflow can be adjusted to enhance the obstacle clearing and separation effect, keeping the harvesting success rate within an acceptable range. This path of adaptation through control strategies is generally more efficient, more controllable, and easier to deploy on-site than purely mechanical modifications in practical applications.

[0031] 10. From a cost and process perspective, this invention results in a reduction in the overall cost of harvesting a unit of fruit and an increase in equipment availability. On the one hand, by using air-blowing to clear obstacles and improve alignment success rate, laser-assisted rapid cutting to reduce movement stroke, airflow-assisted separation to reduce rework of hanging fruit, and receiving and conveying to reduce falling and secondary damage, this continuous chain reduces the average number of actions per fruit and the probability of rework, thereby reducing time and energy costs. On the other hand, by reducing the high-frequency maintenance processes such as replacement, grinding, and lubrication adjustments of easily consumable parts such as blades and scissors, the equipment downtime for maintenance is also reduced accordingly, resulting in a higher availability rate for long-term operation. In addition, the same pneumatic system handles obstacle clearing, separation assistance, and fire suppression, avoiding the additional procurement, wiring, and maintenance costs associated with adding a separate fire extinguishing system for safety, ensuring that improved safety capabilities do not necessarily come with a significant increase in system complexity and manufacturing costs. The multi-objective coordination of this homogeneous pneumatic system, along with the technological innovations of non-contact cutting and non-destructive receiving and conveying, represents a system-level combination that is not easily derived naturally from the common single-point improvement ideas of existing harvesting robots. The synergistic relationship and corresponding effects between its technical means are closer, and it can better support the overall goal of this invention to achieve efficient, non-destructive, and safe continuous operation in the complex environment of orchards. Attached Figure Description

[0032] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a schematic diagram of the overall three-dimensional structure of the non-destructive fruit harvesting robot of the present invention; Figure 2 This is a side view schematic diagram of the non-destructive fruit harvesting robot of the present invention; Figure 3 This is a front view schematic diagram of the non-destructive fruit harvesting robot of the present invention; Figure 4 This is a schematic diagram of the non-destructive fruit harvesting control method in this invention; Figure 5 This is a schematic diagram of the apple picking operation in Embodiment 2 of the present invention (the picking robot completes end alignment in front of the apple tree and performs laser stem cutting and pulsed air blowing in tandem picking). Figure 6 This is a schematic diagram of the citrus harvesting operation in Embodiment 3 of the present invention (the harvesting robot completes end alignment in front of the citrus tree and performs laser cutting and pulsed air blowing in tandem for harvesting). Figure 7 This is a schematic diagram of the overall structure of the harvesting robot with a quadruped robot as the mobile chassis assembly in Embodiment 4 of the present invention.

[0033] The diagram shows: Harvesting execution agency 1; Laser module 11; End mount 12; Airflow generation and control mechanism 2; Air compressor 21; Solenoid valve 22; Gas pipeline 23; Air blowing nozzle 24; 3. Fallen fruit receiving, conveying and collecting mechanism; Fruit-receiving funnel 31; Flexible fruit guide tube 32; Fruit Collection Box 33; 4. Load-bearing and positioning mechanism; Robotic arm 41; Mobile chassis assembly 5; Installation platform 51. Detailed Implementation

[0034] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0035] Example 1: To address the technical problems of existing fruit-picking robots, such as easy damage to fruit during harvesting, low efficiency in cutting fruit stems and difficulty in controlling cutting force, and the risk of overheating and sparks caused by laser cutting operations, this invention provides a non-destructive fruit-picking robot to achieve efficient, stable and safe fruit harvesting. Specifically, it relates to a non-contact, non-destructive fruit-picking robot that combines laser stem cutting and pulsed air blowing. The robot includes a harvesting execution mechanism 1, an airflow generation and control mechanism 2, a fallen fruit receiving and conveying collection mechanism 3, a carrying and positioning mechanism 4, and a moving and walking mechanism. Each mechanism is structurally integrated and functionally divided around the operational chain of fruit stem cutting, fruit separation, fallen fruit receiving, guiding and conveying, and box collection.

[0036] Specifically, the harvesting execution mechanism 1 is used to cut the fruit stalk of the target fruit with energy. It is configured on the top of the bearing and positioning mechanism 4 and achieves its own spatial positioning and attitude adjustment through the bearing and positioning mechanism 4. The airflow generation and control mechanism 2 is configured on the mobile walking mechanism at one end and on the harvesting execution mechanism 1 at the other end. It is used to output high-pressure pulse airflow to the harvesting area in a directional manner. The fallen fruit receiving and conveying collection mechanism 3 is configured on the mobile walking mechanism at one end and on the harvesting execution mechanism 1 at the other end. It is used to receive the cut fallen fruit and guide the fruit into the collection container. The bottom of the bearing and positioning mechanism 4 is configured on the mobile walking mechanism. It is used to stably install the harvesting execution mechanism 1 and achieve its spatial positioning and attitude adjustment. The mobile walking mechanism is used to support the whole machine and realize mobile operation in the orchard environment.

[0037] To enable the harvesting mechanism 1 to reach target fruits at different positions, heights, and orientations, this invention provides a carrying and positioning mechanism 4, which includes a robotic arm 41. The moving mechanism includes a mobile chassis assembly 5, on which a mounting platform 51 is mounted. The lower end of the robotic arm 41 is mounted on the mounting platform 51. The robotic arm 41 has multiple joints and connecting rods. The upper end of the robotic arm 41 is connected to the harvesting mechanism 1, which is used to adjust the position and posture of the harvesting mechanism 1 in space.

[0038] like Figure 1 As shown, the present invention adopts a modular assembly and distributed arrangement method. The picking execution mechanism 1 includes at least a laser module 11 and an end mount 12. The end mount 12 is installed on the upper end of the robotic arm 41. The laser module 11 is configured on the end mount 12. The laser module 11 is used to generate and output laser beams. The laser output end of the laser module 11 is arranged towards the cutting operation area of ​​the fruit stem. The output laser beam can cut the fruit stem.

[0039] To meet the airflow supply and pulse modulation requirements of the harvesting actuator 1, this invention provides an airflow generation and control mechanism 2. The airflow generation and control mechanism 2 constructs an air path using a chain connection of pressure source, valve-controlled modulation, pipeline delivery, and end-point injection. It includes a controller, an air compressor 21, a solenoid valve 22, a gas pipeline 23, and an air-blowing nozzle 24. The air-blowing nozzle 24 is mounted on the end-mounting base 12. The air compressor 21 is fixedly mounted on the mounting platform 51 and is used to output high-pressure air. The output end of the air compressor 21 is connected to one end of the gas pipeline 23, and the other end of the gas pipeline 23 is equipped with the air-blowing nozzle 24. The solenoid valve 22 is located on the gas pipeline 23 between the air compressor 21 and the air-blowing nozzle 24. The inlet end of the solenoid valve 22 is connected to the outlet end of the air compressor 21 through the gas pipeline 23, and the outlet end of the solenoid valve 22 is connected to the air-blowing nozzle 24 through the gas pipeline 23, thus structurally forming a channel for continuous air supply from the chassis end to the harvesting actuator 1.

[0040] Furthermore, the solenoid valve 22 is electrically connected to the controller, and the controller outputs a pulse width modulation control signal to the solenoid valve 22, so that the solenoid valve 22 pulses the gas in a high-frequency opening and closing manner, thereby forming a high-pressure pulsed airflow at the air blowing nozzle 24.

[0041] In practical applications, the gas pipeline 23 is laid between the robotic arm 41 and the mobile chassis assembly 5. The gas pipeline 23 is fixed to the robotic arm 41 by clamps, cable ties, sheaths or internal wiring channels to limit the swinging, pulling and entanglement of the gas pipeline 23 during the movement of the robotic arm 41, and to avoid excessive bending or twisting of the gas pipeline 23 at the joint, which could lead to airtight failure or fatigue damage.

[0042] Under different structural layout requirements, in a preferred embodiment, the solenoid valve 22 is arranged near the end mount 12 or in the middle of the robotic arm 41 to shorten the gas volume between the solenoid valve 22 and the air nozzle 24 and reduce the end injection response delay; in a variation, the solenoid valve 22 is arranged on the mobile chassis assembly 5 to improve maintenance convenience and protection.

[0043] To improve the stability and reliability of the air circuit, the air compressor 21 can also be connected in series with accessories such as a pressure stabilizing element, a filter element, or a one-way valve. These accessories are located between the air compressor 21 and the solenoid valve 22, or between the solenoid valve 22 and the air nozzle 24, to improve air quality, reduce the impact of moisture and particles on the valve body and nozzle, and stabilize pulse output. This invention uses pulse width modulation control of the solenoid valve 22 to form a high-pressure pulsed airflow, used for clearing obstructions around the target fruit, assisting in the efficient separation of the fruit and stem, and providing safety protection by suppressing flames and providing immediate fire extinguishing during laser cutting.

[0044] The pressure source of the airflow generation and control mechanism 2 is arranged on the mobile chassis assembly 5 and connected to the picking execution mechanism 1 through the gas pipeline 23. One end of the fallen fruit receiving and conveying collection mechanism 3 is connected to the picking execution mechanism 1 and the other end is connected to the fruit collection box 33, thereby forming a continuous fruit guiding channel from the end to the chassis and realizing the connection between the operation and the collection action.

[0045] The key structural innovation of this invention lies primarily in the configuration and connection of the harvesting execution mechanism 1. This mechanism includes at least a laser module 11 and an end mount 12 for mounting and fixing the laser module 11 and the air nozzle 24. The laser module 11 is mounted on the end mount 12 and generates and outputs a laser beam. The laser output end is positioned towards the fruit stem cutting area so that the laser beam can cover the fruit stem cutting area when the harvesting execution mechanism 1 reaches the working position. The air nozzle 24 is also fixed on the end mount 12, and is located near the laser output end with its spray direction pointing towards the fruit stem cutting area. This allows the airflow area emitted by the air nozzle 24 to overlap or intersect with the laser beam area in space, enabling the harvesting execution mechanism 1 to simultaneously perform both energy cutting and airflow spraying operations within the same working area.

[0046] Furthermore, the end mount 12 is fixedly connected to the end flange or end connecting plate of the robotic arm 41. The laser module 11 and the air nozzle 24 are respectively fixed to the end mount 12 by fasteners, snaps, or positioning slots to ensure the relative position and attitude between the laser module 11 and the air nozzle 24 are stable and meet the requirements of operational accuracy. The end mount 12 is provided with an air passage interface that communicates with the internal flow channel of the air nozzle 24 to introduce high-pressure gas from the air compressor 21 into the air nozzle 24. The air passage interface can be in the form of quick-connect fittings, threaded fittings, or flange fittings to facilitate assembly, maintenance, and airtight connection.

[0047] To achieve damage-free and stable collection of fallen fruit after cutting, this invention provides a fruit-receiving and conveying collection mechanism 3. The mechanism 3 includes at least a fruit-receiving funnel 31, a flexible fruit-guiding tube 32, and a fruit collection box 33. A continuous fruit-guiding path is formed through the connection of end-receiving, flexible guidance, and base-collection. The fruit-receiving funnel 31 is installed on the end mounting base 12, with its opening facing the expected falling area of ​​the target fruit, allowing the fruit to fall into the funnel 31 after separation from the stem. The funnel outlet of the funnel 31 is connected to one end of the flexible fruit-guiding tube 32, and the other end of the tube is connected to the inlet of the fruit collection box 33, thereby establishing a continuous closed or semi-closed fruit-guiding channel between the funnel 31 and the collection box 33. The fruit-receiving funnel 31 is fixedly connected to the end mounting base 12 via a bracket. The bracket can be an integrated support plate, a connecting arm, or an adjustable connector, so that the fruit-receiving funnel 31 maintains a stable spatial relationship with the laser module 11 and the air blowing nozzle 24 and meets the requirements for the fruit-receiving position.

[0048] Furthermore, the flexible fruit guide tube 32 is made of flexible material and is laid along the path from the robotic arm 41 to the fruit collection box 33. The flexible fruit guide tube 32 is fixed to the robotic arm 41 or the mobile chassis assembly 5 by a fixing clamp to avoid excessive swinging, squeezing or bending of the fruit guide tube when the robotic arm 41 moves, which would affect the smooth flow of fruit. The fruit collection box 33 is fixedly installed on the mobile chassis assembly 5. The fruit collection box 33 is provided with a receiving cavity for collecting fruit and an inlet that communicates with the flexible fruit guide tube 32. The inlet and the end of the flexible fruit guide tube 32 are connected by clamps, flanges or plugs to achieve stable introduction. In the optional structure, the inlet size, inlet shape and funnel inclination angle of the fruit receiving funnel 31 can be set according to the fruit size range. The inner diameter, tube wall hardness and minimum bending radius of the flexible fruit guide tube 32 can be configured according to the fruit size and conveying length to ensure that the fruit passes smoothly under gravity or weak airflow and reduce violent collisions with the tube wall.

[0049] The end of the robotic arm 41 is fixedly connected to the end mount 12, allowing the laser module 11, air nozzle 24, and fruit-receiving funnel 31 to move with the robotic arm 41, thereby achieving alignment and operation of the target fruit stem cutting area. To ensure the continuity and reliability of the air supply and fruit guiding channel during the movement of the robotic arm, the gas pipeline 23 and the flexible fruit guiding tube 32 are both laid along the robotic arm 41 and fixed relative to the robotic arm 41. The end of the gas pipeline 23 is connected to the air nozzle 24, and the end of the flexible fruit guiding tube 32 is connected to the fruit-receiving funnel 31, so that the robotic arm 41 can maintain the continuous connection of the air supply and the fruit guiding channel during the movement. Guide rings, flexible sleeves, or transition allowance sections can be set near the joints of the robotic arm to alleviate local stress concentration caused by movement and improve pipeline life.

[0050] To meet the mobile operation requirements in orchard environments, this invention includes a mobile walking mechanism, which is a mobile chassis assembly 5. The mobile chassis assembly 5 supports components such as the air compressor 21, fruit collection box 33, and robotic arm 41, providing structural support and mobility for the entire machine. The mobile chassis assembly 5 can adopt a tracked or wheeled walking structure. The mobile chassis assembly 5 includes a chassis, with a mounting platform 51 located in the central area of ​​the chassis. The robotic arm 41 is fixedly mounted on the mounting platform 51. The air compressor 21 is fixedly mounted on the other side or front of the chassis, and the fruit collection box 33 is fixedly mounted on one side or rear of the chassis, achieving a stable center of gravity, compact structure, and convenient maintenance. Installation space can be provided inside or on the surface of the chassis for arranging controllers, power supplies, and pneumatic accessories, allowing the pneumatic, control, and collection modules to form a reasonable spatial partition on the chassis and reducing mutual interference.

[0051] This invention also provides a non-destructive fruit harvesting control method, specifically, a non-contact, non-destructive fruit harvesting control method based on the synergy of laser cutting and pulsed air blowing. This method defines the action chain of end alignment, air path establishment, pulse modulation, synergistic cutting, and collection in a step-by-step manner, specifically including the following steps: End alignment step: Control the robotic arm 41 to drive the picking execution mechanism 1 to move to the vicinity of the target fruit and complete the posture adjustment, so that the output direction of the laser module 11 is aligned with the fruit stem cutting area, and at the same time, the inlet of the fruit receiving funnel 31 is aligned with the expected fruit drop area of ​​the target fruit, thereby establishing consistency between the cutting point alignment and the fruit drop receiving alignment in space. Pulse air blowing preparation steps: Control the air compressor 21 to establish air circuit pressure and control the solenoid valve 22 to enter the controlled opening and closing state, so that the air blowing nozzle 24 has the conditions to output high-pressure pulse airflow. Collaborative operation steps: While the laser module 11 is cutting the fruit stem, or within a preset time window before and after the cutting, the solenoid valve 22 is controlled to open and close according to the pulse width modulation signal, so that the air nozzle 24 outputs high-pressure pulsed airflow to the fruit stem cutting area. Fallen fruit receiving and conveying steps: After the target fruit separates from the fruit stalk, it falls into the fruit receiving funnel 31 and is guided into the fruit collection box 33 through the flexible fruit guide tube 32 to complete the collection; End-of-line reset and next target step: Control the robotic arm 41 to drive the picking execution mechanism 1 away from the current working position and enter the alignment and picking cycle of the next target fruit, thereby achieving continuous picking.

[0052] In the optional parameter configuration, the frequency range of the pulse width modulation signal output by the controller can be set to 10 Hz to 500 Hz, the duty cycle range can be set to 5% to 95%, and the output pressure of the air compressor 21 can be set to 0.2 MPa to 1.0 MPa, so as to adapt to different degrees of shading, different fruit stem strengths, and different nozzle structures and working distances. The above parameter range is used to describe the optional implementation range of control and structure, so as to form coverage of actual engineering implementation without limiting a specific single value.

[0053] Example 2: This embodiment is a preferred example of Embodiment 1. A typical apple orchard is selected as the application background. The row spacing of apple trees is approximately 3.0–4.0 m, the tree spacing is approximately 1.2–2.0 m, and the canopy height is approximately 2.0–3.5 m. The target for harvesting is mature apples with a single fruit diameter of approximately 60–95 mm and a single fruit weight of approximately 150–350 g. The fruit stalk (pedicel) diameter is typically 2–5 mm and its shape is variable, often accompanied by surrounding branches and leaves that obstruct the view. The structure of the harvesting robot in this embodiment is as follows: Figures 1-3 As shown, the harvesting control process is as follows: Figure 4As shown, the apple picking operation status is as follows: Figure 5 As shown. To ensure structural manufacturability and operational feasibility, this embodiment provides a set of achievable specific structural dimensions and operating parameters. However, it should be understood that these parameters are for illustrative purposes only and do not constitute a limitation on the scope of protection of this invention.

[0054] To adapt to the soft, undulating, and weedy environment of the orchard, the mobile chassis assembly 5 in this embodiment adopts a tracked walking mechanism with a chassis width of approximately 0.55–0.85 m and a ground clearance of approximately 60–120 mm. The robotic arm 41 adopts a multi-joint robotic arm structure (e.g., 6 degrees of freedom), with an arm span of approximately 0.8–1.2 m and a rated end-effector load of approximately 3–5 kg, to meet the accessibility and end-effector load requirements within the apple tree canopy. The fruit collection box 33 can be set in the middle or rear area of ​​the chassis, with a box volume of, for example, 30–80 L. An elastic liner can be laid inside the box to reduce the risk of secondary collisions with fallen fruit inside the box.

[0055] To highlight the key structural innovations of this invention, this embodiment integrates a laser stem-cutting and pulsed air-blowing collaborative structure at the end of the robotic arm 41. The laser module 11 is fixed to the end-mount 12, with the laser output facing the stem-cutting area. The air-blowing nozzle 24 is also mounted on the end-mount 12 and located adjacent to the laser output, ensuring that the spray axis of the nozzle 24 points towards the stem-cutting area. The airflow area and the laser beam area overlap or intersect spatially, thus achieving collaborative operation on the same harvesting area. To ensure stem-cutting efficiency and avoid unnecessary thermal impact on the fruit surface, this embodiment exemplarily employs a near-infrared laser scheme: the laser module 11 can be a fiber laser or a semiconductor laser, with an output power of, for example, 20–80 W (40 W in the example), and the output can be continuous or pulsed; the equivalent diameter of the laser spot at the stem is, for example, 0.3–1.2 mm (0.6 mm in the example), and the working distance between the end and the stem is, for example, 20–80 mm (45 mm in the example).

[0056] In terms of structural arrangement, the center of the air-blowing nozzle 24 is offset laterally from the laser beam axis by, for example, 10–40 mm (25 mm in the example), and the angle between the spray direction and the laser beam axis is, for example, 5°–30° (15° in the example). This allows the airflow to cover the fruit stem cutting point and its surrounding obstructed area, while preventing the airflow from directly impacting the optical emitting surface of the laser module 11. The air-blowing nozzle 24 can be made of metal or wear-resistant engineering plastic material, with a nozzle diameter of, for example, 2–6 mm (4 mm in the example). The nozzle housing can be equipped with a protective structure (not shown) to reduce the impact of orchard dust and branch collisions on the nozzle.

[0057] The airflow generation and control mechanism 2 in this embodiment includes an air compressor 21, a solenoid valve 22, a gas pipeline 23, and an air blowing nozzle 24. The air compressor 21 can be a small piston or scroll compressor powered by DC, with an output pressure of, for example, 0.2 to 1.0 MPa (0.6 MPa in the example) and a rated flow rate of, for example, 30 to 120 L / min (60 L / min in the example). An air storage and pressure stabilization unit can be set at the outlet of the air compressor 21 to reduce pressure fluctuations. The solenoid valve 22 is electrically connected to the controller, and the controller outputs a pulse width modulation (PWM) drive signal to make the solenoid valve 22 pulse modulate the gas in a high-frequency opening and closing manner, so that the air blowing nozzle 24 outputs a high-pressure airflow with obvious pulse characteristics. To balance obstacle clearance intensity, response speed, and gas consumption, the PWM frequency in this embodiment can be set to 10–500 Hz (120 Hz in the example), and the duty cycle can be set to 5%–95% (35% in the example). When stronger obstacle clearance or fire suppression capabilities are required, the duty cycle can be temporarily increased to 60%–90% and maintained for 0.2–1.0 s. The gas pipeline 23 can be a pressure-resistant flexible hose or composite pipe (e.g., pressure ≥1.5 MPa), and is fixed in sections along the outside of the joint of the robotic arm 41 by clamps or cable ties. Bending allowance is reserved at each joint of the robotic arm 41 to avoid excessive pulling and bending caused by the movement of the robotic arm 41. If necessary, a short section of flexible buffer tube is set near the end to absorb transient vibrations and improve sealing reliability.

[0058] To achieve controllable reception, buffering, guiding, and collection of apples after stem cutting, this embodiment sets up a receiving funnel 31, a flexible fruit guide tube 32, and a fruit collection box 33 to form a continuous fruit guiding path. The receiving funnel 31 is fixed to the end mounting base 12 or its support, with the funnel inlet facing the expected landing area of ​​the target apple. The effective diameter of the inlet is, for example, 140-260 mm (200 mm in the example). The inner wall of the funnel can be made of food-grade engineering plastics (e.g., PP, PE) or stainless steel, and can be covered with a low-friction or buffer lining (e.g., a thin layer of TPU or a flocked layer) to reduce the risk of abrasion when the fruit comes into contact with the funnel. The outlet of the receiving funnel 31 is connected to the first end of the flexible fruit guide tube 32, and the second end of the flexible fruit guide tube 32 is connected to the inlet of the fruit collection box 33, thereby combining the end reception and the chassis collection into a continuous channel.

[0059] To prevent apples from getting stuck during the fruit guiding process, the inner diameter of the flexible fruit guiding tube 32 in this embodiment can be set to 70-140 mm (110 mm in this example). The tube wall material can be silicone, TPU, or PVC reinforced flexible tubing, and the tube wall thickness can be, for example, 2-4 mm. The flexible fruit guiding tube 32 is laid along the path from the robotic arm 41 to the fruit collection box 33, and is relatively fixed to the robotic arm 41 and the chassis structure by fixing clamps, so that the fruit guiding tube will not be squeezed and flattened or entangled with external structures when the robotic arm 41 moves. The fruit collection box 33 is provided with a fruit inlet and is connected to the flexible fruit guiding tube 32 in a sealed or semi-sealed manner. A layered buffer structure can be set inside the box to reduce crush damage when multiple fruits are piled up.

[0060] Regarding the control and operational procedures for apple harvesting, this embodiment follows... Figure 4 The steps shown are executed. First, S1 end alignment is performed, controlling the robotic arm 41 to drive the picking execution mechanism 1 to a position near the target apple, and adjusting the end posture so that the output direction of the laser module 11 is aligned with the fruit stem cutting area, while simultaneously aligning the inlet of the fruit receiving funnel 31 with the expected fruit drop area of ​​the target apple.

[0061] To improve alignment reliability, the robotic arm 41 can adopt a coarse positioning + fine positioning motion strategy: the end-effector speed in the coarse positioning stage is, for example, 0.1 to 0.3 m / s; when the end-effector is about 150 to 250 mm from the target, it enters the fine positioning stage, where the end-effector speed is, for example, 5 to 30 mm / s, and the relative deviation between the laser cutting point and the fruit stalk is controlled within ±1 to ±3 mm (±2 mm in the example), and the end-effector working distance is maintained at 20 to 80 mm (45 mm in the example). After alignment, the S2 pulse air blowing preparation is performed, controlling the air compressor 21 to establish the air circuit pressure, stabilizing the system pressure at a preset value (e.g., 0.6 MPa ± 0.05 MPa), and placing the solenoid valve 22 in a controlled opening and closing state, so that the air blowing nozzle 24 is ready to output high-pressure pulse airflow at any time; in this stage, a short-term pre-blowing airflow (e.g., 0.1 to 0.5 s, 120 Hz, duty cycle 35%) can be selected to lightly clean the leaves or dust around the fruit stalk, creating a more stable working window for subsequent cutting.

[0062] Then, the S3 collaborative operation begins. While the laser module 11 is cutting the fruit stem, or within a preset time window before or after the cutting, the solenoid valve 22 is controlled to open and close according to the PWM signal, so that the air nozzle 24 outputs a high-pressure pulsed airflow to the fruit stem cutting area. For apple stem diameters typically ranging from 2 to 5 mm, this embodiment can employ the following achievable parameters: the laser module 11 output power is, for example, 30 to 60 W (40 W in the example), the duration of a single irradiation is, for example, 0.15 to 0.80 s (0.35 s in the example), and small-range sweeping or micro-movement compensation can be performed near the stem cross-section (e.g., micro-movement at the end along the stem axis ±1 to ±3 mm) to improve the success rate of cutting stems in different postures; the pulsed airflow is turned on 0.1 to 0.3 s before cutting and turned off 0.1 to 0.5 s after cutting (0.2 s before and 0.3 s after in the example), the PWM frequency is, for example, 80 to 200 Hz (120 Hz in the example), the duty cycle is, for example, 20% to 60% (35% in the example), and the distance between the nozzle and the stem cutting point is, for example, 30 to 120 mm (70 mm in the example). Within this collaborative window, the high-pressure pulsed airflow can be used to maintain the working field of vision and clear obstructions, and can also disturb the separation interface at the moment the fruit stem is cut, causing the target apple to separate from the fruit stem and fall towards the fruit receiving funnel 31. If flames or abnormal burning signs appear during the laser burning process (which can be observed manually or by a flame / temperature sensor, not shown), the controller can immediately cut off the laser output and increase the duty cycle of the solenoid valve 22 to 80%–95% for 0.3–1.0 s to enhance the ability of the jet airflow to extinguish and suppress the flames, and then return to normal operating parameters or enter the next round of alignment.

[0063] After the target apple separates from its stem, it enters S4 for receiving and conveying fallen apples. Under the influence of gravity, the target apple falls into the receiving funnel 31 and then enters the flexible guide tube 32 through the outlet of the receiving funnel 31, and is finally guided into the fruit collection box 33 for collection. To ensure smooth conveying, in this embodiment, the flexible guide tube 32 can be arranged with an overall downward slope, avoiding sharp bends with a radius smaller than the minimum bending radius along the way, and a flexible buffer section is set near the entrance of the fruit collection box 33 to further reduce the speed of the apple entering the box. After the single fruit is picked, it enters S5 for end reset and the next target. The robotic arm 41 is controlled to drive the picking execution mechanism 1 away from the current working position, for example, retracting 100-300 mm and lifting or moving laterally to avoid obstacles. Then, the moving chassis assembly 5 or the robotic arm 41 enters the alignment and picking cycle of the next target apple, thereby realizing continuous picking operations.

[0064] Through the above-described structural configuration and process control, this embodiment can complete the cutting of fruit stems in apple picking scenarios using a combined laser stem cutting and pulsed air blowing end-effector method. The falling fruit is received and transported through the continuous channel of the fruit receiving funnel 31, the flexible fruit guide tube 32, and the fruit collection box 33. At the same time, the high-pressure pulsed airflow output by the air blowing nozzle 24 can be used to quickly extinguish flames when necessary. Thus, this embodiment has an operable, manufacturable, and repeatable engineered operation mode.

[0065] Example 3: This embodiment is another preferred example of Embodiment 1. In this embodiment, a typical citrus orchard (such as navel oranges and tangerines) is selected as the application background. Citrus tree canopies are typically dense with branches and leaves, with numerous leaves that significantly obstruct the view. Fruits are mostly distributed between the outer edge of the canopy and the inner branches. The diameter of a single fruit is generally about 50–90 mm, and the weight is about 80–300 g. The diameter of the fruit stalk (pedicel) is typically about 1.5–4.0 mm, and the stalk length is relatively short. The fruit often closely obstructs the view of the stalk during cutting, resulting in a small visible window and difficulty in alignment. Citrus peel has a certain degree of toughness but is easily bruised / damaged, affecting its appearance. Furthermore, citrus harvesting often requires retaining an appropriate stalk length or avoiding pulling or tearing the stalk to reduce the risk of juice vesicle rupture and epidermal damage.

[0066] The harvesting robot in this embodiment has the same structure as in embodiment 1; see the overall structure below. Figures 1-3 For control procedures, please refer to [link / reference]. Figure 4 See the status of citrus harvesting operations. Figure 6 To enhance feasibility, this embodiment provides a set of structural layouts and operating parameters suitable for citrus harvesting conditions. These parameters are for illustrative purposes only and do not constitute a limitation on the scope of protection of this invention.

[0067] In this embodiment, the air compressor 21 and the fruit collection box 33 are mounted on the mobile chassis assembly 5, the robotic arm 41 is fixed at the mounting platform 51 of the mobile chassis assembly 5, the gas pipeline 23 is led from the chassis end to the end of the robotic arm 41 and connected to the air blowing nozzle 24, and the solenoid valve 22 is set between the air compressor 21 and the air blowing nozzle 24 to realize airflow pulse modulation.

[0068] In this embodiment, the mobile chassis assembly 5 preferably adopts a tracked walking structure to adapt to the soft ground and local undulations in the orchard. The chassis width is, for example, 0.55–0.85 m, and the ground clearance is, for example, 70–150 mm. The robotic arm 41 is a multi-joint robotic arm with a reach of, for example, 0.9–1.3 m and a rated end-effector load of, for example, 3–6 kg, to cover the outer edge and inner harvesting space of the citrus tree canopy. The fruit collection box 33 can be set with a volume range of 40–100 L, and the box is lined with elastic cushioning padding or has layered partitions to reduce the risk of collision and abrasion after the citrus is placed in the box.

[0069] In this embodiment, the harvesting mechanism 1 adopts a combined structure of laser cutting and pulsed air blowing to adapt to the working conditions characterized by dense citrus branches and leaves, strong shading, short fruit stalks, and small alignment windows. The laser module 11 is fixed on the end mounting base 12, with the laser output end facing the fruit stalk cutting operation area; the air blowing nozzle 24 is located near the laser output end and the spray direction is pointed towards the fruit stalk cutting operation area, so that the airflow action area and the laser beam action area overlap or intersect in space.

[0070] To increase the exposure of the fruit stalk cutting point and reduce the risk of accidental irradiation of the fruit peel, in this embodiment, the lateral offset of the air-blowing nozzle 24 relative to the laser beam axis can be set to 15–45 mm (30 mm in the example), the angle between the spray direction and the laser beam axis can be set to 10°–35° (20° in the example), and the distance between the nozzle and the fruit stalk cutting point can be set to 40–130 mm (80 mm in the example). This allows the airflow to first act on the leaves surrounding the fruit and create a short-term swing, thereby forming a more stable fruit stalk cutting window. The nozzle diameter of the air-blowing nozzle 24 can be set to 2–6 mm (3.5 mm in the example), and the nozzle material can be stainless steel or wear-resistant engineering plastic. A protective cover can be added to the nozzle housing to prevent contact with branches and leaves and dust intrusion. In this embodiment, the laser module 11 may employ a near-infrared laser (such as a fiber laser or a semiconductor laser) with an output power of, for example, 15–70 W (35 W in the example), an equivalent spot diameter of, for example, 0.3–1.0 mm (0.5 mm in the example), and a working distance between the end and the fruit stalk of, for example, 20–70 mm (40 mm in the example), in order to achieve rapid cutting and reduce the spread of heat effects within a shorter fruit stalk window.

[0071] The airflow generation and control mechanism 2 in this embodiment includes an air compressor 21, a solenoid valve 22, a gas pipeline 23, and an air blowing nozzle 24. The air compressor 21 is preferably a DC-powered reciprocating compressor or a scroll compressor, with an output pressure of, for example, 0.25–0.9 MPa (0.55 MPa in the example) and a rated flow rate of, for example, 30–120 L / min (70 L / min in the example). A small air storage tank and a pressure stabilizing element can be installed at the compressor outlet to improve the stability of the pulsed airflow. The solenoid valve 22 is electrically connected to the controller, and the controller outputs a PWM drive signal to cause the solenoid valve 22 to perform high-frequency opening and closing modulation of the gas.

[0072] In this embodiment, considering the stronger shading of citrus fruits and the need for a more penetrating air-blowing obstacle-clearing effect, the PWM frequency can be set to 20–500 Hz (160 Hz in the example), and the duty cycle can be set to 10%–80% (45% in the example). During the alignment stage, a higher frequency and lower duty cycle (e.g., 200 Hz, 20% duty cycle) can be used to achieve a shaking-type obstacle clearing. During the cutting and separation assistance stage, a medium-high duty cycle (e.g., 160 Hz, 45% duty cycle) can be used to enhance local external force disturbance and promote fruit drop. When flames or abnormal burning signs appear, the duty cycle can be increased to 80%–95% for 0.2–1.0 s to enhance the extinguishing ability. The gas pipeline 23 can be a flexible pipeline with a pressure resistance of ≥1.5 MPa, and is laid and fixed along the robotic arm 41. Bending allowance is reserved at the joints, and a short flexible buffer tube can be installed at the end to reduce the impact of transient pressure fluctuations and mechanical vibrations on the sealing connection.

[0073] The fruit-receiving and transporting collection mechanism 3 of this embodiment includes a fruit-receiving funnel 31, a flexible fruit-guiding tube 32, and a fruit collection box 33, used to receive and transport the cut citrus fruits into the box in a non-contact manner. The fruit-receiving funnel 31 is fixedly installed at the harvesting execution mechanism 1, with its inlet facing the expected fruit-falling area of ​​the target citrus fruit. Considering that the diameter of a single citrus fruit is usually smaller than or close to that of an apple and that the branches and leaves provide stronger shading, the effective diameter of the inlet of the fruit-receiving funnel 31 in this embodiment can be set to 130-240 mm (180 mm in the example). The inner wall of the funnel can be made of a low-friction, easy-to-clean material (such as PP, PE, or stainless steel) and can be covered with a thin cushioning liner (such as a TPU / silicone coating, not shown) to reduce the risk of fruit peel abrasion. The outlet of the fruit-receiving funnel 31 is connected to the first end of the flexible fruit-guiding tube 32, and the second end of the flexible fruit-guiding tube 32 is connected to the inlet of the fruit collection box 33. The inner diameter of the flexible fruit-guiding tube 32 can be set to 60-120 mm (95 mm in the example). The tube wall material can be silicone or TPU reinforced flexible tubing. The pipeline layout should maintain an overall downward trend as much as possible and avoid sharp bends to improve the smoothness of fruit guidance and reduce the rolling and collision of fruits in the tube. The fruit collection box 33 is provided with a receiving cavity and an inlet. The inlet is connected to the flexible fruit-guiding tube 32 by a clamp or quick-connect structure. The box can be equipped with a buffer layer, a flexible mesh bag, or a compartment partition (not shown) to reduce the abrasion and skin damage caused by the collision of citrus fruits after they are put into the box in batches.

[0074] The citrus harvesting control and operation process in this embodiment follows Figure 4 Execution. First, S1 end alignment is performed. The robotic arm 41 drives the picking mechanism 1 to move to a position near the target citrus and adjusts its posture so that the output direction of the laser module 11 is aligned with the fruit stem cutting area, and the inlet of the fruit receiving funnel 31 is aligned with the expected fruit drop area of ​​the target citrus. Due to the stronger shading of the citrus and the shorter fruit stem resulting in a smaller alignment window, this embodiment can adopt a pre-blowing and fine positioning alignment strategy: when the end is about 150-250 mm away from the target, a short-duty cycle pulse air blow (e.g., 200 Hz, duty cycle 15%-25%, duration 0.2-0.6 s) is activated to spread the leaves and expose the fruit stem area; then, the fine positioning stage is entered, and the end moving speed is controlled at 5-25 mm / s, and the relative deviation between the laser cutting point and the fruit stem is controlled within ±1-±2 mm (±1.5 mm in the example), while maintaining the end working distance at 25-60 mm (40 mm in the example). After alignment is completed, the S2 pulse air blowing preparation is performed. The air compressor 21 is controlled to establish the air circuit pressure and stabilize it at a preset value (e.g., 0.55 MPa ± 0.05 MPa). The solenoid valve 22 is controlled to enter the controlled opening and closing state, so that the air blowing nozzle 24 has the conditions to output high-pressure pulse airflow.

[0075] Then, the S3 collaborative operation begins. While the laser module 11 is cutting the fruit stem, or within a preset time window before or after the cutting, the solenoid valve 22 is controlled to open and close according to the PWM signal, so that the air nozzle 24 outputs a high-pressure pulsed airflow to the fruit stem cutting area. Considering the characteristics of citrus fruit stalks with a diameter of 1.5–4.0 mm and relatively short stalks, this embodiment can adopt the following achievable parameters: the output power of laser module 11 is 25–55 W (35 W in the example), the duration of a single irradiation is 0.12–0.60 s (0.28 s in the example), and small-range end-effector compensation can be performed near the stalk cutting point (e.g., ±1–±2 mm along the stalk direction, or ±0.5–±1.5 mm perpendicular to the stalk direction) to improve the cutting success rate and reduce the risk of accidental irradiation of the peel; the pulsed airflow can be turned on 0.1–0.3 s before cutting and turned off 0.1–0.4 s after cutting (0.15 s before and 0.25 s after in the example), and the PWM frequency is 80–250 Hz (160 Hz in the example). The laser output is set at 25%–60% (45% in this example) to continuously clear obstacles in the cutting area and disturb the separation interface, causing the citrus fruit to separate from the stem and fall towards the fruit-receiving funnel 31. If flames or abnormal burning occur during the cutting process, the controller can immediately stop the laser output and increase the PWM duty cycle to 80%–95% for 0.2–0.8 s to enhance the flame extinguishing effect, then return to normal operation or proceed to the next alignment.

[0076] After the citrus fruit separates from its stem, it enters the S4 stage for receiving and transporting fallen fruit. Under gravity, the citrus falls into the receiving funnel 31, then through the outlet of the funnel 31 into the flexible guide tube 32, and finally into the fruit collection box 33 for collection. To reduce the rolling and collision of citrus fruits within the guide tube, this embodiment can set the path of the flexible guide tube 32 to a gentler slope and a larger bending radius. The inner wall of the guide tube can be made of a material with a low coefficient of friction and a certain degree of elasticity. A flexible buffer section or soft curtain can be set at the entrance of the fruit collection box 33 to reduce the speed at which the fruit enters the box. After the single fruit is harvested, the process enters the S5 stage for end reset and the next target. The robotic arm 41 drives the harvesting execution mechanism 1 away from the current working position (e.g., retracting 100-250 mm and raising to avoid obstacles). Then, the robotic arm 41 turns or moves the chassis assembly 5 to enter the alignment and harvesting cycle of the next target citrus fruit, thereby realizing continuous citrus harvesting operations.

[0077] Through the above-described structural configuration and step-by-step control, this embodiment can achieve obstacle clearing before alignment and separation during operation under typical working conditions of dense citrus branches and leaves, short fruit stalks, and small alignment windows. The laser module 11 can quickly cut off the fruit stalks. At the same time, the continuous fruit guiding channel formed by the fruit receiving funnel 31, flexible fruit guiding tube 32, and fruit collection box 33 can realize the receiving and non-destructive transportation and collection of fallen fruits. In the event that the laser cutting may generate flames, they can be quickly extinguished by the pulse airflow. Thus, this embodiment constitutes an engineering embodiment suitable for citrus picking scenarios.

[0078] Example 4: This embodiment is a variation of Embodiment 1, using a quadruped robot as the harvesting embodiment for the mobile chassis assembly 5. In this embodiment, the mobile chassis assembly 5 no longer employs a tracked or wheeled structure, but instead uses a quadruped robot chassis to adapt to complex terrain environments such as mountain orchards, terraced orchards, and understory economic operation areas, characterized by soft, undulating ground, numerous furrows, tree roots, rock obstacles, and frequent slope changes. A typical advantage of the quadruped chassis is that it allows for gait adjustment to select crossing and landing points, thereby maintaining stability on uneven ground and providing greater attitude control for the precise alignment of the robotic arm 41. The overall structure of this embodiment is shown in the diagram below. Figure 7 As shown, the airflow generation and control mechanism 2 includes an air compressor 21, a solenoid valve 22, a gas pipeline 23, and an air nozzle 24. The picking execution mechanism and the air jet end are still integrated at the end of the robotic arm 41. The end is equipped with a laser module 11 and an air nozzle 24. The fruit receiving and conveying collection mechanism 3 still includes a fruit receiving funnel 31, a flexible fruit guide tube 32, and a fruit collection box 33. The difference is that the four-legged mobile chassis assembly 5 simultaneously undertakes the functions of obstacle crossing, machine height and posture leveling, and anti-disturbance support during the picking process, so that the whole machine can maintain the end alignment and the continuity of the fruit guiding channel under rugged terrain conditions.

[0079] like Figure 7 As shown, the quadrupedal mobile chassis assembly 5 includes a body platform and four controllable moving leg structures. Each leg has at least three active joints to achieve forward and backward swinging, lifting, and lateral support. The feet can be equipped with rubber anti-slip pads or textured grounding structures to improve grip and reduce slippage. In this embodiment, the quadrupedal chassis has an exemplary body length of 0.7–1.2 m, a width of 0.35–0.65 m, an adjustable body height of 0.30–0.55 m, a maximum obstacle-crossing height of 0.10–0.25 m, a maximum climbing ability of 15°–25° (depending on foot friction and control strategies), and a typical walking speed of 0.2–1.0 m / s. These parameters enable the chassis to approach the target tree and perform local fine-tuning positioning in narrow passages between tree rows, undulating ground, and scattered obstacles.

[0080] The robotic arm 41 is fixedly connected to the chassis platform via a reinforced mounting base. The mounting base can be a metal load-bearing plate and a reinforcing rib structure to transfer the reaction torque of the robotic arm during operation to the chassis body. To reduce the impact of walking vibration on the laser cutting accuracy at the end effector, vibration damping pads or vibration isolation supports can be installed between the base of the robotic arm 41 and the chassis platform. The vibration damping pad material can be rubber / polyurethane elastomer, and the hardness and thickness are matched according to the robotic arm load and vibration frequency, thus balancing structural rigidity and vibration suppression between walking and stationary cutting conditions. The fruit collection box 33 is installed on the chassis platform of the four-legged mobile chassis assembly 5, preferably located near the chassis center of gravity to reduce pitching and tilting caused by changes in the load of the collection box. The volume of the fruit collection box 33 can be 30-80 L, and a soft buffer layer or compartment partitions can be installed inside the box to reduce collisions caused by multiple fruits piling up. The air compressor 21 is fixedly installed at the rear or side of the machine platform. A vibration damping connection can be set between the compressor and the machine platform to reduce the transmission of compressor working vibration to the robotic arm 41 and reduce the risk of fatigue damage to the connection between the air compressor 21 and the pipeline caused by chassis travel impact.

[0081] In this embodiment, the harvesting execution mechanism 1 still adopts a laser stalk cutting + pulsed air blowing collaborative structure: the laser module 11 is fixed on the end mounting base 12, with the laser output end facing the stalk cutting operation area; the air blowing nozzle 24 is fixed on the same end mounting base 12 and located near the laser output end, with its spray direction pointing towards the stalk cutting area, so that the action area of ​​the sprayed airflow overlaps or intersects with the action area of ​​the laser beam in space. To adapt to the dynamic attitude adjustment of the quadruped platform, this embodiment can design the end mounting base 12 as a rigid frame structure, and use a dual positioning and fixing method of positioning pins + fasteners for the laser module 11 and the air blowing nozzle 24 to ensure that the relative geometric relationship between the laser beam axis and the nozzle spray axis remains stable when switching between chassis walking and stationary operation. The laser module 11 can be a fiber laser or a semiconductor laser, with an exemplary output power of 20 to 80 W (e.g., 40 W), an equivalent spot diameter of 0.3 to 1.2 mm (e.g., 0.6 mm), and a working distance of 20 to 80 mm (e.g., 45 mm) between the end and the fruit stalk. The air-blowing nozzle 24 has a nozzle diameter of 2 to 6 mm (e.g., 4 mm), a distance of 40 to 130 mm (e.g., 75 mm) between the nozzle and the fruit stalk cutting point, an angle of 10° to 30° (e.g., 15°) between the spray direction and the laser beam axis, and a lateral offset of 10 to 45 mm (e.g., 25 mm) to allow the airflow to open the leaves and clear obstructions near the cutting point under the condition of branch and leaf obstruction.

[0082] In this embodiment, the airflow generation and control mechanism 2 still includes an air compressor 21, a solenoid valve 22, a gas pipeline 23, and an air blowing nozzle 24. The air compressor 21 can be a DC-powered reciprocating compressor with an output pressure of 0.2–1.0 MPa (e.g., 0.6 MPa) and a rated flow rate of 30–120 L / min (e.g., 60 L / min). A gas storage and pressure stabilizing unit can be installed at the compressor outlet to reduce pressure fluctuations and improve pulse response consistency. The solenoid valve 22 is electrically connected to the controller. The controller outputs a PWM signal to drive the solenoid valve 22 to pulse-modulate the gas in a high-frequency opening and closing manner, so that the air blowing nozzle 24 outputs a high-pressure pulsed airflow. The PWM frequency can be set to 10–500 Hz (e.g., 120 Hz), and the duty cycle can be set to 5%–95% (e.g., 35%) to adapt to different degrees of shading and different stem strengths. Since the quadruped platform may experience slight vibrations and attitude changes in complex terrain, this embodiment preferably positions the solenoid valve 22 near the end mount 12 or the middle section of the robotic arm 41 to shorten the effective gas volume between the valve and the nozzle and reduce airflow response delay. The gas pipeline 23 is laid out along the outer or inner wiring channel of the robotic arm 41 and fixed in sections, with a bend allowance reserved at each joint. An S-shaped slack section is also reserved at the connection between the body and the robotic arm to absorb relative displacement caused by changes in chassis attitude, avoiding excessive pipe pulling, bending, or interference with leg movements. To improve field applicability, a filter element and a one-way valve can be connected in series in the pneumatic system. The filter element reduces the impact of dust and moisture on the solenoid valve 22 and the air nozzle 24, while the one-way valve prevents pressure backflow and improves pulse output stability.

[0083] In this embodiment, the fruit-receiving and conveying collection mechanism 3 still includes a fruit-receiving funnel 31, a flexible fruit-guiding tube 32, and a fruit collection box 33. It achieves non-contact and non-destructive collection through a continuous channel of end-receiving, flexible guidance, and chassis entry into the box. The fruit-receiving funnel 31 is installed at the end of the robotic arm 41 and fixed to the end mounting seat 12 by a bracket. Its inlet faces the expected fruit-receiving area. In view of the possibility of body height adjustment and end-position change of the four-legged platform, this embodiment can set the fruit-receiving funnel 31 to an adjustable connection structure relative to the end mounting seat 12 (e.g., elongated hole + locking structure or ball joint + locking structure) to calibrate the receiving direction of the funnel inlet during the assembly and calibration stage. The effective diameter of the inlet of the fruit-collecting funnel 31 can be 140–260 mm (e.g., 200 mm). The inner wall material can be PP / PE engineering plastic or stainless steel, covered with a thin buffer liner to reduce abrasion. The first end of the flexible fruit guide tube 32 is connected to the outlet of the fruit-collecting funnel 31, and the second end is connected to the inlet of the fruit collection box 33. The inner diameter of the guide tube can be 70–140 mm (e.g., 110 mm), and the material can be silicone or TPU reinforced flexible tubing. It is laid and fixed along the path of the robotic arm 41 and the chassis platform. To adapt to the changes in the relative spatial posture of the machine body during the gait movement of the four-legged chassis, this embodiment preferably sets a gentle bending margin section near the machine platform of the flexible fruit guide tube 32, so that the guide tube can absorb the slight movement of the machine body without being flattened, ensuring that the fruit guide channel remains unobstructed. A flexible curtain or buffer guide section (not shown) can be set at the inlet of the fruit collection box 33 to reduce the speed of the fruit entering the box and reduce secondary collisions inside the box.

[0084] The operation control in this embodiment can be implemented. Figure 4Based on the harvesting process shown, a four-legged stabilization and posture adjustment step is added to ensure the positioning accuracy and safety of laser cutting. When approaching the target tree, the four-legged mobile chassis assembly 5 uses a walking gait (e.g., slow diagonal gait or crawling gait) to enter a predetermined position near the tree canopy, with a predetermined positioning distance of 0.3–1.0 m. After reaching the position, the chassis switches to a stabilization support mode, adjusting the body height and pitch / roll angles through the four-legged joints to keep the platform within a preset posture range (e.g., pitch and roll controlled within ±2° respectively). If necessary, small steps are used to adjust and change the relative orientation of the machine and the tree. Then, in S1, the end alignment is initiated. The robotic arm 41 drives the picking mechanism 1 to move to a position near the target fruit and adjusts its posture so that the laser module 11 is aligned with the fruit stem cutting area, while the inlet of the fruit receiving funnel 31 is aligned with the expected fruit drop area. In the four-legged chassis stationary mode, the end precision positioning speed can be set to 5–30 mm / s, and the relative deviation between the cutting point and the fruit stem is controlled within ±1–±3 mm (e.g., ±2 mm). After entering S2, pulse air blowing preparation, the air compressor 21 is controlled to establish the air circuit pressure and stabilize it at the set value (e.g., 0.6 MPa ± 0.05 MPa). The solenoid valve 22 is controlled to enter the controlled opening and closing state. If necessary, a low duty cycle pre-blowing of 0.1–0.5 s can be performed first to clear obstructing leaves and improve the alignment window. Subsequently, the S3 collaborative operation begins. While the laser module 11 is cutting the fruit stem, or within a preset time window before or after cutting, the solenoid valve 22 is controlled to open and close according to the PWM signal, causing the air nozzle 24 to output high-pressure pulsed airflow to the fruit stem cutting area. Exemplary parameters are: laser power 30-60 W, irradiation duration 0.15-0.80 s (e.g., 40 W, 0.35 s), airflow PWM frequency 80-200 Hz, duty cycle 20%-60% (e.g., 120 Hz, 35%), and it can be set to open 0.1-0.3 s before cutting and close 0.1-0.5 s after cutting to enhance the continuity of obstacle clearing and separation assistance. If a flame or abnormal burning is detected during the cutting process (which can be detected by a flame, temperature sensor, or manual observation, not shown), the controller can immediately stop the laser output and increase the duty cycle of the solenoid valve 22 to 80%–95% for 0.2–1.0 s to improve the extinguishing effect, and maintain the four-legged chassis in a stationary posture until the risk is eliminated. After cutting, the process enters S4 for fruit collection and conveying. The fruit falls into the fruit receiving funnel 31 and is guided through the flexible fruit guide tube 32 into the fruit collection box 33 for collection. Finally, the process enters S5 for end reset and the next target. The robotic arm 41 retracts and lifts to avoid obstacles. The four-legged mobile chassis assembly 5 performs micro-step adjustments or short-distance travel according to the position of the next target, and switches back to the stationary support mode to enter the next harvesting cycle, thereby achieving continuous harvesting under complex terrain conditions.

[0085] Through the above-described structure and process configuration, this embodiment, supported by the quadrupedal mobile chassis assembly 5, enables the harvesting robot to approach, stop, level, and micro-position on uneven ground. Under a stable posture, it drives the robotic arm 41 to complete the coordinated operation of the laser module 11 cutting the handle and the air blowing nozzle 24 pulse air blowing. At the same time, relying on the continuous channel formed by the fruit receiving funnel 31, the flexible fruit guide tube 32, and the fruit collection box 33, it realizes the receiving, conveying, and collecting of fallen fruit. This constitutes a manufacturable, repeatable, and engineering-deployable embodiment suitable for orchards in mountainous / sloping / obstacle terrain.

[0086] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0087] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A non-destructive fruit-harvesting robot, characterized in that, include The mobile walking mechanism is used to support the entire machine and enable mobile operations in the orchard environment; The bearing and positioning mechanism (4) is disposed at the bottom on the mobile walking mechanism; The picking execution mechanism (1) is used to cut off the fruit stalk of the target fruit. It is arranged on the top of the bearing and positioning mechanism (4) and realizes its own spatial positioning and posture adjustment through the bearing and positioning mechanism (4). The airflow generation and control mechanism (2) is configured on the mobile walking mechanism at one end and on the picking execution mechanism (1) at the other end, and is used to output high-pressure pulse airflow to the picking area in a directional manner. The fruit-receiving and transporting collection mechanism (3) is configured on the mobile walking mechanism at one end and on the picking execution mechanism (1) at the other end, and is used to receive the cut fruit and guide the fruit into the collection container.

2. The non-destructive fruit harvesting robot according to claim 1, characterized in that, The harvesting execution mechanism (1) includes at least a laser module (11) and an end mount (12). The end mount (12) is mounted on the upper end of the bearing and positioning mechanism (4). The laser module (11) is disposed on the end mount (12). The laser module (11) is used to generate and output a laser beam. The laser output end of the laser module (11) is arranged toward the cutting operation area of ​​the fruit stem.

3. The non-destructive fruit harvesting robot according to claim 2, characterized in that, The bearing and positioning mechanism (4) includes a robotic arm (41), and the moving walking mechanism includes a mobile chassis assembly (5). The mobile chassis assembly (5) has an installation platform (51). The lower end of the robotic arm (41) is installed on the installation platform (51), and the upper end of the robotic arm (41) is connected to the end mounting seat (12).

4. The non-destructive fruit harvesting robot according to claim 1 or 3, characterized in that, The airflow generation and control mechanism (2) includes a controller, an air compressor (21), a solenoid valve (22), a gas pipeline (23), and an air blowing nozzle (24). The air nozzle (24) is mounted on the end mounting base (12) of the harvesting actuator (1), the air compressor (21) is mounted on the moving walking mechanism and is used to output high-pressure air, the output end of the air compressor (21) is connected to one end of the gas pipeline (23), the air nozzle (24) is mounted on the other end of the gas pipeline (23), and the solenoid valve (22) is set on the gas pipeline (23); The solenoid valve (22) is electrically connected to the controller. The controller can output a pulse width modulation control signal to the solenoid valve (22) so that the solenoid valve (22) pulses the gas in a high-frequency opening and closing manner, thereby forming a high-pressure pulse airflow at the air blowing nozzle (24).

5. The non-destructive fruit harvesting robot according to claim 4, characterized in that, The laser output end of the laser module (11) of the harvesting execution mechanism (1) is arranged facing the fruit stem cutting operation area, and the air blowing nozzle (24) points the spray direction to the fruit stem cutting operation area, so that the airflow action area of ​​the air blowing nozzle (24) and the laser beam action area overlap or intersect in space.

6. The non-destructive fruit harvesting robot according to claim 1, characterized in that, The fruit receiving and transporting collection mechanism (3) includes at least a fruit receiving funnel (31), a flexible fruit guide tube (32), and a fruit collection box (33). The fruit-receiving funnel (31) is installed on the end mounting base (12) of the harvesting execution mechanism (1). The opening of the fruit-receiving funnel (31) is arranged facing the expected fruit drop area of ​​the target fruit. The funnel outlet of the fruit-receiving funnel (31) is connected to one end of the flexible fruit guide tube (32), and the other end of the flexible fruit guide tube (32) is connected to the fruit inlet of the fruit collection box (33).

7. The non-destructive fruit harvesting robot according to claim 1, characterized in that, The mobile walking mechanism can adopt any of the following structural forms: Tracked walking structure; Wheeled walking structure; Quadrupedal locomotion structure.

8. The non-destructive fruit harvesting robot according to claim 1, characterized in that, The gas pipeline (23) of the bearing and positioning mechanism (4) is fixed relative to the robotic arm (41) by means of clamps, cable ties, sheaths or internal wiring channels; The flexible fruit guide tube (32) of the fruit receiving and transporting collection mechanism (3) is made of flexible material and is laid along the path from the robotic arm (41) to the fruit collection box (33).

9. A method for controlling fruit harvesting without damage, characterized in that, Includes the following steps: End alignment step: Control the robotic arm (41) to drive the picking execution mechanism (1) to move to the vicinity of the target fruit and complete the posture adjustment, so that the output direction of the laser module (11) is aligned with the fruit stem cutting area, and at the same time, the inlet of the fruit receiving funnel (31) is aligned with the expected fruit drop area of ​​the target fruit, thereby establishing consistency between the cutting point alignment and the fruit drop receiving alignment in space. Pulse air blowing preparation steps: Control the air compressor (21) to establish air circuit pressure and control the solenoid valve (22) to enter the controlled opening and closing state, so that the air blowing nozzle (24) has the conditions to output high-pressure pulse airflow; Collaborative operation steps: While the laser module (11) cuts the fruit stem, or within a preset time window before and after the cutting, the solenoid valve (22) is controlled to open and close according to the pulse width modulation signal, so that the air nozzle (24) outputs high-pressure pulsed airflow to the fruit stem cutting area. Fallen fruit receiving and conveying steps: After the target fruit is separated from the fruit stalk, it falls into the fruit receiving funnel (31) and is guided into the fruit collection box (33) through the flexible fruit guide tube (32) to complete the collection; End reset and next target step: Control the robotic arm (41) to drive the picking execution mechanism (1) away from the current working position and enter the alignment and picking cycle of the next target fruit, thereby realizing continuous picking.

10. The non-destructive fruit harvesting control method according to claim 9, characterized in that, If a flame or abnormal burning sign appears during the laser burning process, the controller can immediately cut off the laser output and increase the duty cycle of the solenoid valve (22) to 80% to 95% for 0.3 to 1.0 s to enhance the ability of the jet airflow to blow out and suppress the flame, and then return to normal operating parameters or enter the next round of alignment.

Images