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This study introduces a reduced-order leg dynamic model to simplify the controller design and enhance robustness. The proposed multi-loop control scheme tackles tracking control issues in legged robots, including joint angle and contact-force regulation, disturbance suppression, measurement delay, and motor saturation avoidance. Firstly, model predictive control (MPC) and sliding mode control (SMC) schemes are developed using a simplified model, and their stability is analyzed using the Lyapunov method. Numerical simulations under two disturbances validate the superior tracking performance of the SMC scheme. Secondly, an Nth-order linear active disturbance rejection control (LADRC) is designed based on a simplified model and optimization problems. The second-order LADRC-SMC scheme reduces the contact-force control error in the SMC scheme by ten times. Finally, a fourth-order LADRC-SMC with a Smith Predictor (LADRC-SMC-SP) scheme is formulated, employing each loop controller independently. This scheme simplifies the design and enhances performance. Compared to numerical simulations of the above and existing schemes, the LADRC-SMC-SP scheme eliminates delay oscillations, shortens convergence time, and demonstrates fast force-position tracking responses, minimal overshoot, and strong disturbance rejection. The peak contact-force error in the LADRC-SMC-SP scheme was ten times smaller than that in the LADRC-SMC scheme. The integral square error (ISE) values for the tracking errors of joint angles θ1 and θ2, and contact force f, are 1.6636×10−28 rad2⋅s, 1.7983×10−28 rad2⋅s, and 1.8062×10−30 N2⋅s, respectively. These significant improvements in control performance address the challenges in single-leg dynamic systems, effectively handling disturbances, delays, and motor saturation.

Objective SLE is a common multisystem autoimmune disease with chronic inflammation. Many efficacy evaluation indicators of randomised clinical trials (RCTs) for SLE have been proposed but the comparability remains unknown. We aim to explore the preference and comparability of indicators reporting response rate and provide basis for primary outcome selection when evaluating the efficacy of SLE pharmaceutical treatment.Methods We systematically searched three databases and three registries to identify pharmacological intervention-controlled SLE RCTs. Relative discriminations between indicators were assessed by the Bayesian hierarchical linear mixed model.Results 33 RCTs met our inclusion criteria and we compared eight of the most commonly used indicators reporting response rate. SLE Disease Activity Index 4 (SLEDAI-4) and SLE Responder Index 4 were considered the best recommended indicators reporting response rate to discriminate the pharmacological efficacy. Indicator preference was altered by disease severity, classification of drugs and outcome of trials, but SLEDAI-4 had robust efficacy in discriminating ability for most interventions. Of note, BILAG Index-based Combined Lupus Assessment showed efficacy in trials covering all-severity patients, as well as non-biologics RCTs. The British Isles Lupus Assessment Group response and Physician’s Global Assessment response were more cautious in evaluating disease changes. Serious adverse event was often applied to evaluate the safety and tolerability of treatments rather than efficacy.Conclusions The impressionable efficacy discrimination ability of indicators highlights the importance of flexibility and comprehensiveness when choosing primary outcome(s). As for trials that are only evaluated by SLEDAI-4, attention should be paid to outcome interpretation to avoid the exaggeration of treatment efficacy. Further subgroup analyses are limited by the number of included RCTs.PROSPERO registration number CRD42022334517.

Motion control is crucial for multilegged robot locomotion and task completion. This study aims to address the fundamental challenges of inadequate foot tracking and weak leg compliance control in multilegged robot motions. The first section summarizes and discusses the feasibility and operability of smooth motion for multilegged robots based on the necessary conditions and application value of walking over complicated and unstructured terrain. The second to fourth sections present a qualitative research method of literature review to study the effects of several factors on the smooth motion of multilegged robots, including foot force perception and motion planning, active compliance control, gait stability, and Deep Reinforcement Learning (DRL) control. We conducted a case analysis of multilegged robots using traditional Nonlinear Model Predictive Control (NMPC), biomimetic Central Pattern Generator (CPG), and DRL control in the latest international open-source projects to help readers further follow the latest open-source algorithms for legged robot motion control. In addition, we analyze the challenges these influencing factors face in optimization and provide suggestions for effectively promoting the realization of review objectives. In the fifth section, we discuss the challenges of springy gait and intelligent switching control in solving the problems of poor foot tracking and weak leg compliance. We explore and forecast the potential application of the Probability Density Function (PDF) control of the foot force in the smooth motion of multilegged robots. In the sixth section, we systematically discuss, analyze, and summarize the existing problems in this research field. We also highlight the shortcomings of existing research methods, look forward to future research areas, and highlight the obstacles that need to be overcome to promote future research in this field.

Abstract Objective Standard medical treatment for early non‐small cell lung cancer (NSCLC) is surgery; however, stereotactic body radiotherapy (SBRT) can be a viable substitute for elderly patients who can no longer tolerate or refuse surgery. The unsurpassed care for elderly patients with early NSCLC remains inconclusive. We conducted a propensity‐score matching analysis to compare the efficacy and side‐effects of SBRT and video‐assisted thoracic surgery (VATS) in elderly patients with pathologically‐proven early NSCLC. Methods This single‐institution retrospective study included 310 elderly patients who underwent VATS (n = 180) or SBRT (n = 130) from January 2011 to November 2018 at the Tianjin Medical University Cancer Institute and Hospital. Sex, performance status, pathology type, Charlson Comorbidity Index, and T‐stage according to the eighth tumor node metastasis classification were considered when performing propensity‐score matching. Results After propensity‐score matching, 71 patients were included in each group for analysis. A median follow‐up period of 53.5 months was observed for all patients; 72 and 53 months for patients undergoing VATS and SBRT, respectively. Overall survival (p = 0.492), progression‐free survival (p = 0.294), locoregional recurrence‐free survival (p = 0.866), and distant metastasis‐free survival (p = 0.452) did not differ significantly between the VATS and SBRT groups. Multivariate analysis showed a significant correlation between the T‐stage and overall survival. However, treatment‐related toxicity was lower in the SBRT group than in the VATS group. Conclusions SBRT is an option comparable with surgery for elderly patients with pathologically‐proven early‐stage NSCLC.