The continuously deformable geometry of modular robots makes it difficult to define a fixed representation for reconfiguration planning and analysis. This letter introduces a square-cell abstraction that maps deformable rhombus modules to fixed-size grid cells while retaining physically interpretable local motions through two primitives, pivoting and shearing. Under this abstraction, we prove that every non-straight edge-connected configuration with $N \geq 7$ can be transformed to a fixed canonical staircase using only admissible primitive motions. Since these motions are reversible, any two configurations in this class are mutually reconfigurable. The proof is constructive and directly yields a staircase-canonicalization planner that transports removable boundary modules while preserving connectivity. As a practical enhancement, we further introduce a boundary-to-delivery lookahead selector that ranks admissible high level choices without affecting the completeness guarantee. Experiments demonstrate the constructive reconfiguration process and show that the selector substantially reduces planning time, while reference comparisons indicate lower planning times than the prior framework over the shared module counts.
Jie Gu, Tingting Wang, Hong Gao et al.· 0 citations
Background Frailty is a core manifestation of geriatric syndromes, and its decompensated state is associated with adverse outcomes, yet standardized assessment criteria are lacking. Methods From January 2022 to June 2024, 538 patients with geriatric syndromes were prospectively enrolled. Frailty was assessed using the Fried phenotype. The optimal left ventricular ejection fraction (LVEF) cutoff (≤51.2%) for identifying frailty decompensation was determined via ROC curve analysis. Risk factors for frailty progression and the impact of decompensation on major adverse events (all-cause mortality, stroke, cardiovascular events, urinary incontinence) and hospitalization frequency were analyzed. Results The prevalence of frailty was 44.05%. Independent risk factors for frailty progression included advanced age, malnutrition (low MNA-SF score and albumin), impaired cardiac function (low LVEF, NYHA class III–IV), anxiety/depression, and low hemoglobin. LVEF ≤ 51.2% effectively defined frailty decompensation (AUC = 0.781). Decompensation was an independent risk factor for urinary incontinence (OR = 4.113, P = 0.049) and for increased hospitalization frequency (IRR = 1.628, P = 0.003). Conclusions This study identifies multisystem risk factors for frailty progression, proposes an exploratory, internally derived LVEF threshold for identifying frailty decompensation, which should be considered hypothesis-generating and requires external validation before clinical application, and confirms that decompensation significantly increases the risk of urinary incontinence and healthcare burden.
