In order to overcome the shortcomings of the previous obstacle avoidance algorithms,an obstacle avoidance algorithm applicable to multiple mobile obstacles was proposed.The minimum prediction distance between obstacle...In order to overcome the shortcomings of the previous obstacle avoidance algorithms,an obstacle avoidance algorithm applicable to multiple mobile obstacles was proposed.The minimum prediction distance between obstacles and a manipulator was obtained according to the states of obstacles and transformed to escape velocity of the corresponding link of the manipulator.The escape velocity was introduced to the gradient projection method to obtain the joint velocity of the manipulator so as to complete the obstacle avoidance trajectory planning.A7-DOF manipulator was used in the simulation,and the results verified the effectiveness of the algorithm.展开更多
Intensive labor chores for broiler production could be reduced by using automated systems.However,broilers’response toward automated systems remains unclear.The experiments were conducted to determine the avoidance d...Intensive labor chores for broiler production could be reduced by using automated systems.However,broilers’response toward automated systems remains unclear.The experiments were conducted to determine the avoidance distance(AD)and the fleeing speed(FS)of 4-8 weeks old broilers toward two aerial systems,a rail with a dummy arm and a drone,operated at different speeds(0.2-1.2 m/s),and heights(0.3-1.8 m)in a commercial broiler house.The broiler AD to a human assessor was also determined for comparison.Results show that the overall mean and standard error(SE)of broiler AD were 63±3 cm for the assessor,58±1 cm for the rail,and 85±1 cm for the drone.As bird age increased from week 4 to week 8,broiler AD reduced significantly from 82 to 45 cm for the rail but showed no significant change for the drone.As the operational speed increased,broiler AD significantly increased from 54 cm(0.2 m/s)to 62 cm(0.4 m/s)for the rail,and from 81 cm(0.4 m/s)to 89 cm(1.2 m/s)for the drone.As the operational height increased,broiler AD increased from 54 cm(0.3 m)to 57 cm(1.5 m)for the rail and 81 cm(1.2 m)to 88 cm(1.8 m)for the drone.Overall mean and SE of broiler FS were 0.21±0.01 m/s for the rail and 0.65±0.01 m/s for the drone.As bird age increased from week 4 to week 8,the mean broiler FS decreased from 0.47 to 0.07 m/s for the rail and from 0.84 to 0.16 m/s for the drone.Increasing operational speed from 0.2 to 0.4 m/s for the rail and from 0.4 to 1.2 m/s for the drone significantly increased the mean FS from 0.18 to 0.24 m/s and from 0.52 to 0.78 m/s,respectively.Increasing the height of the rail from 0.3 to 1.5 m decreased the broiler FS from 0.27 to 0.16 m/s.However,increasing drone height from 1.2 to 1.8 m retained a similar FS.The outcomes of this study can help to better understand the interaction of broilers with aerial systems and provide insights into the optimization of robotic operational strategies while maintaining good broiler welfare production.展开更多
基金Supported by Ministeral Level Advanced Research Foundation(65822576)Beijing Municipal Education Commission(KM201310858004,KM201310858001)
文摘In order to overcome the shortcomings of the previous obstacle avoidance algorithms,an obstacle avoidance algorithm applicable to multiple mobile obstacles was proposed.The minimum prediction distance between obstacles and a manipulator was obtained according to the states of obstacles and transformed to escape velocity of the corresponding link of the manipulator.The escape velocity was introduced to the gradient projection method to obtain the joint velocity of the manipulator so as to complete the obstacle avoidance trajectory planning.A7-DOF manipulator was used in the simulation,and the results verified the effectiveness of the algorithm.
文摘Intensive labor chores for broiler production could be reduced by using automated systems.However,broilers’response toward automated systems remains unclear.The experiments were conducted to determine the avoidance distance(AD)and the fleeing speed(FS)of 4-8 weeks old broilers toward two aerial systems,a rail with a dummy arm and a drone,operated at different speeds(0.2-1.2 m/s),and heights(0.3-1.8 m)in a commercial broiler house.The broiler AD to a human assessor was also determined for comparison.Results show that the overall mean and standard error(SE)of broiler AD were 63±3 cm for the assessor,58±1 cm for the rail,and 85±1 cm for the drone.As bird age increased from week 4 to week 8,broiler AD reduced significantly from 82 to 45 cm for the rail but showed no significant change for the drone.As the operational speed increased,broiler AD significantly increased from 54 cm(0.2 m/s)to 62 cm(0.4 m/s)for the rail,and from 81 cm(0.4 m/s)to 89 cm(1.2 m/s)for the drone.As the operational height increased,broiler AD increased from 54 cm(0.3 m)to 57 cm(1.5 m)for the rail and 81 cm(1.2 m)to 88 cm(1.8 m)for the drone.Overall mean and SE of broiler FS were 0.21±0.01 m/s for the rail and 0.65±0.01 m/s for the drone.As bird age increased from week 4 to week 8,the mean broiler FS decreased from 0.47 to 0.07 m/s for the rail and from 0.84 to 0.16 m/s for the drone.Increasing operational speed from 0.2 to 0.4 m/s for the rail and from 0.4 to 1.2 m/s for the drone significantly increased the mean FS from 0.18 to 0.24 m/s and from 0.52 to 0.78 m/s,respectively.Increasing the height of the rail from 0.3 to 1.5 m decreased the broiler FS from 0.27 to 0.16 m/s.However,increasing drone height from 1.2 to 1.8 m retained a similar FS.The outcomes of this study can help to better understand the interaction of broilers with aerial systems and provide insights into the optimization of robotic operational strategies while maintaining good broiler welfare production.
