Based on the mechanical model of an elastic rod,a new trajectory design method was established.The advantages of the suspender line trajectory in reducing drag and torsion were compared,and the main controlling factor...Based on the mechanical model of an elastic rod,a new trajectory design method was established.The advantages of the suspender line trajectory in reducing drag and torsion were compared,and the main controlling factors of drag and torque and their influence rules were analyzed.Research shows that the suspender line trajectory reduces drag and torque more effectively than the conventional trajectory in a certain parameter interval and has more controllable parameters than that of the catenary trajectory.The main factors affecting the drag reduction and torque reduction of the suspender line trajectory include the friction coefficient,vertical distance,horizontal distance,and deviation angle at the initial point in the suspended section.The larger the friction coefficient and deviation angle,the less the drag reduction and torque reduction.The suspender line trajectory has the best drag reduction effect when the horizontal and vertical distances are more than 3000 m and the ratio is close to 1.5.The drag in sliding drilling can be reduced up to 60%,and the torque in rotary drilling can be reduced by a maximum of 40%.Therefore,the trajectory design of the suspender line has unique application prospects in deep extended-reach wells.展开更多
The formation control of multiple unmanned aerial vehicles(multi-UAVs)has always been a research hotspot.Based on the straight line trajectory,a multi-UAVs target point assignment algorithm based on the assignment pro...The formation control of multiple unmanned aerial vehicles(multi-UAVs)has always been a research hotspot.Based on the straight line trajectory,a multi-UAVs target point assignment algorithm based on the assignment probability is proposed to achieve the shortest overall formation path of multi-UAVs with low complexity and reduce the energy consumption.In order to avoid the collision between UAVs in the formation process,the concept of safety ball is introduced,and the collision detection based on continuous motion of two time slots and the lane occupation detection after motion is proposed to avoid collision between UAVs.Based on the idea of game theory,a method of UAV motion form setting based on the maximization of interests is proposed,including the maximization of self-interest and the maximization of formation interest is proposed,so that multi-UAVs can complete the formation task quickly and reasonably with the linear trajectory assigned in advance.Finally,through simulation verification,the multi-UAVs target assignment algorithm based on the assignment probability proposed in this paper can effectively reduce the total path length,and the UAV motion selection method based on the maximization interests can effectively complete the task formation.展开更多
基金Supported by the National Science and Technology Major Project(2016ZX05060-014)PetroChina Major Science and Technology Project(ZD2019-183-005)。
文摘Based on the mechanical model of an elastic rod,a new trajectory design method was established.The advantages of the suspender line trajectory in reducing drag and torsion were compared,and the main controlling factors of drag and torque and their influence rules were analyzed.Research shows that the suspender line trajectory reduces drag and torque more effectively than the conventional trajectory in a certain parameter interval and has more controllable parameters than that of the catenary trajectory.The main factors affecting the drag reduction and torque reduction of the suspender line trajectory include the friction coefficient,vertical distance,horizontal distance,and deviation angle at the initial point in the suspended section.The larger the friction coefficient and deviation angle,the less the drag reduction and torque reduction.The suspender line trajectory has the best drag reduction effect when the horizontal and vertical distances are more than 3000 m and the ratio is close to 1.5.The drag in sliding drilling can be reduced up to 60%,and the torque in rotary drilling can be reduced by a maximum of 40%.Therefore,the trajectory design of the suspender line has unique application prospects in deep extended-reach wells.
基金supported by the Basic Scientific Research Business Expenses of Central Universities(3072022QBZ0806)。
文摘The formation control of multiple unmanned aerial vehicles(multi-UAVs)has always been a research hotspot.Based on the straight line trajectory,a multi-UAVs target point assignment algorithm based on the assignment probability is proposed to achieve the shortest overall formation path of multi-UAVs with low complexity and reduce the energy consumption.In order to avoid the collision between UAVs in the formation process,the concept of safety ball is introduced,and the collision detection based on continuous motion of two time slots and the lane occupation detection after motion is proposed to avoid collision between UAVs.Based on the idea of game theory,a method of UAV motion form setting based on the maximization of interests is proposed,including the maximization of self-interest and the maximization of formation interest is proposed,so that multi-UAVs can complete the formation task quickly and reasonably with the linear trajectory assigned in advance.Finally,through simulation verification,the multi-UAVs target assignment algorithm based on the assignment probability proposed in this paper can effectively reduce the total path length,and the UAV motion selection method based on the maximization interests can effectively complete the task formation.
