This paper presents a joint state and parameter estimation method for aircraft engine performance degradation tracking. Contrast to previously reported techniques on that view parameters in the evolution model as constants, presented this treats time-varying variables account varying rates at different stages of operation. Transition are performed by particle filtering (PF) under Bayesian inference framework. To address sample impoverishment problem due discrete resampling, which is inherent...

The leakage of urban natural gas pipes may cause significant safety hazards and economic losses. Autonomous inspection these using quadruped robots is an effective method. This paper proposes a hybrid algorithm combining optimized RRT* DWA(ORRT*-DWA) to solve the path planning problem faced by in environment. Firstly, through three strategies, including probability-based sampling, extended node filtering, adaptive step size. ORRT* then integrated with DWA form new algorithm. ORRT*-DWA...

The existing dynamic path planning algorithm cannot properly solve the problem of wheeled robot on slope ground with moving obstacles. To slow convergence rate in training phase DDQN, based Tree-Double Deep Q Network (TDDQN) is proposed. discards detected incomplete and over-detected paths by optimizing tree structure, combines DDQN method structure method. Firstly, used to select best action current state after performing fewer actions, so as obtain candidate that meets conditions. And...

As a type of autonomous underwater vehicle (AUV), gliders (UG) are getting increasing attention in ocean exploration. To save energy and satisfy the mission requirements longer voyage, shape optimization for UGs has become key technique research focus. In this paper, conventional UG, including its fuselage hydrofoil, is optimized, which aims to decrease average resistance one motion cycle. operate progress complex object, multiple free form deformation (FFD) volumes established geometric...

Background: Quadruped crawling robots face challenges when working in the raised terrain of a slope. The robot is affected by gravity and gait under this terrain. ground reaction force on its hind legs relatively large. This has strict requirements for structure planning quadruped robot. Objective: Aimed at problem large rear slope, slope-triangular walking strategy based layered CGP generation method proposed. Methods: Three-dimensional model created SOLIDWORKS. kinematic established, foot...

Background: In recent years, patents have shown that upper-limb rehabilitation robots play a significant role in home-based training for stroke hemiplegia patients. Changes muscle tension during the flaccid paralysis phase cause robot to deviate from predetermined motion trajectory. This poses challenge mathematical modeling of and design nonlinear extended state observer (NESO). Objective: To address problem trajectory tracking errors caused by when patient's changes, method based on...

Background: In recent years, observers have been crucial for controlling quadruped crawling robots, especially feed-forward compensation in complex terrains. However, their tracking performance continuous convex terrains requires optimization. Objective: order to improve the mobility of robots by reducing posture adjustment time terrain, a finite-time observer with integration elements and optimized gait planning is proposed. Methods: First, buffer phase introduced into tripod adapt terrain...

Purpose Assisted training using upper limb rehabilitation robots is beneficial for flaccid paralysis patients in recovering their functional abilities. In the assisted mode, patient’s motor ability limited by factors such as muscle tension, and it prone robot to deviate from prescribed trajectory. A sliding mode control method based on a fixed time observer proposed address problem of delayed trajectory tracking response caused external disturbances patient limbs. Design/methodology/approach...

Purpose To improve the position tracking efficiency of upper-limb rehabilitation robot for stroke hemiplegia patients, optimization Learning rate membership function based on fuzzy impedance controller is propose. Design/methodology/approach First, impaired limb’s damping and stiffness parameters evaluating its physical recovery condition are online estimated by using weighted least squares method recursive algorithm. Second, control with rule has been designed optimal parameters. Finally,...

Background: Quadruped crawling robots will be faced with stability problems when walking on a raised slope. The of robot is affected by gait planning and selection its foothold in this terrain. slope reaction force anterior posterior legs uneven. strategy should achieve good performance for the quadruped robot. Objective: Aimed at uneven problem slope, patent method optimization using reinforcement learning based search proposed. Methods: kinematic model created D-H coordinate method....

Background: In recent years, patents suggest that four-wheeled robots have been widely used in outdoor reconnaissance fields. However, the emergency obstacle avoidance of robot on slope is affected by angle and friction coefficient slope, its motor torque yaw are prone to abrupt changes, causing slip greatly. According relevant literature, PID control methods (dual-loop linear control) make current fluctuate greatly during process. Hence, controller needs be optimized. Objective: This study...

Background: In recent years, literature has suggested that quadruped crawling robots have been widely used in the field of reconnaissance on rugged mountain trails. Under influence gait and slope, joint angle robot changes drastically when landing, resulting drop down from slope. This strict requirements for planning control robots. Objective: The aim this study is to set up a novel impedance controller based gearshift integral PID improve stability during climbing continuous Methods:...