Diseño, puesta en marcha y mejoras de prototipo robótico para inspección visual en estanques industriales

152 p.En esta memoria se trabajó en el diseño y construcción de un prototipo robótico, el cual tiene como misión capturar imágenes de alta definición al interior de estanques industriales, los que específicamente guardan químicos utilizados en la industria de la celulosa en Chile. Este trabajo se presenta como el desarrollo proyectado y ejecutado durante la segunda práctica profesional en una empresa de mantención predictiva, que es la principal empresa del rubro que presta servicios a CMPC y Arauco en todas sus plantas del país. La primera etapa consistió en la investigación de modelos de dispositivos específicos que cumplen con diferentes funciones de inspección visual, enfocándose principalmente en la forma de acceso a los estanques, calidad de imagen entregada y manejo de la información. Una vez conocidos los elementos necesarios para el desarrollo del prototipo se prosiguió con el diseño del robot el que debía priorizar la captura de imágenes de alta calidad o generar imágenes panorámicas del interior de los estanques a analizar. Después de visitar en terreno los estanques a inspeccionar, se fabricó el diseño propuesto el cual fue capaz de analizar, en una primera etapa, dos estanques de licor negro en la planta Nueva Aldea de Celulosa Arauco, la cual evidenció las primeras fallas del prototipo en cuanto a su calibración, control y manejo de la información. Corregidos estos problemas, se realizaron pruebas en los mismos estanques, en las plantas de Valdivia también de Arauco, con resultados exitosos en sus dos principales funciones, zoom y panorámica del interior de los estanques analizados. Posteriormente se propuso un reporte de inspección visual para formalizar el trabajo realizado y mostrar las imágenes capturadas por el prototipo. Cabe destacar que para los encargados de mantenimiento de Arauco, la propuesta del robot como nuevo método de inspección visual, marcó una nueva etapa en el desarrollo de esta disciplina, la que hasta el momento les implica grandes gastos y valioso tiempo al momento de tomar decisiones con respecto a que hacer frente a una falla detectada. Por último se presentan posibles mejoras al diseño del prototipo, las cuales se espera contribuyan para la finalización del proyecto y su posterior aplicación como método de inspección del interior de estanques industriales./ABSTRACT:This memoir worked on the designing and construction of a robotic prototype, whose mission is to capture high-resolution pictures inside industrial tanks, which specifically save chemicals used on Chile’s cellulose industry. This work is presented as the development projected and executed during the second professional practice on a predictive maintenance company which is the main company that serves CMPC and Arauco across the country.The first step consisted on the investigation of specific device models where everyone had a different visual inspection purpose, focusing mainly on the method of going into the tanks, image quality and information managing. Once the necessary elements for the prototype’s development were known, the next step was designing the robot that had to prioritize on the taking of high-quality pictures or the generation of panoramic picture of the inside of the tanks. After visiting the location subject to inspection, the fabrication of the proposed design followed, which had the ability to analyze, at first, two black liquor tanks on the plant of Nueva Aldea of Celulosa Arauco, which evidenced the prototype’s first flaws regarding it’s calibration, control and information management. Once this problems were fixed, some tests were made on the same tanks mentioned before with successful results on the prototype’s main functions (zoom and panoramic view on the inside of the tanks). Later, a visual inspection report was proposed in order to formalize the work that was done and show the pictures the prototype could capture.Something that must be highlighted is that for the workers in charge of Arauco’s maintenance, the proposition of a robot as a method of visual inspection generated a new phase of this discipline’s development, one which until now has implied big spending and valuable time when making decisions regarding what to do when a flaw is detected.Finally, there have been possible improvements presented regarding the prototype’s design, for which is hoped to contribute on the project’s completion and future application as an inspection method inside industrial tanks

Stoma-free survival after anastomotic leak following rectal cancer resection: worldwide cohort of 2470 patients

Background: The optimal treatment of anastomotic leak after rectal cancer resection is unclear. This worldwide cohort study aimed to provide an overview of four treatment strategies applied. Methods: Patients from 216 centres and 45 countries with anastomotic leak after rectal cancer resection between 2014 and 2018 were included. Treatment was categorized as salvage surgery, faecal diversion with passive or active (vacuum) drainage, and no primary/secondary faecal diversion. The primary outcome was 1-year stoma-free survival. In addition, passive and active drainage were compared using propensity score matching (2: 1). Results: Of 2470 evaluable patients, 388 (16.0 per cent) underwent salvage surgery, 1524 (62.0 per cent) passive drainage, 278 (11.0 per cent) active drainage, and 280 (11.0 per cent) had no faecal diversion. One-year stoma-free survival rates were 13.7, 48.3, 48.2, and 65.4 per cent respectively. Propensity score matching resulted in 556 patients with passive and 278 with active drainage. There was no statistically significant difference between these groups in 1-year stoma-free survival (OR 0.95, 95 per cent c.i. 0.66 to 1.33), with a risk difference of -1.1 (95 per cent c.i. -9.0 to 7.0) per cent. After active drainage, more patients required secondary salvage surgery (OR 2.32, 1.49 to 3.59), prolonged hospital admission (an additional 6 (95 per cent c.i. 2 to 10) days), and ICU admission (OR 1.41, 1.02 to 1.94). Mean duration of leak healing did not differ significantly (an additional 12 (-28 to 52) days). Conclusion: Primary salvage surgery or omission of faecal diversion likely correspond to the most severe and least severe leaks respectively. In patients with diverted leaks, stoma-free survival did not differ statistically between passive and active drainage, although the increased risk of secondary salvage surgery and ICU admission suggests residual confounding

Stoma-free Survival After Rectal Cancer Resection With Anastomotic Leakage: Development and Validation of a Prediction Model in a Large International Cohort.

Objective:To develop and validate a prediction model (STOMA score) for 1-year stoma-free survival in patients with rectal cancer (RC) with anastomotic leakage (AL).Background:AL after RC resection often results in a permanent stoma.Methods:This international retrospective cohort study (TENTACLE-Rectum) encompassed 216 participating centres and included patients who developed AL after RC surgery between 2014 and 2018. Clinically relevant predictors for 1-year stoma-free survival were included in uni and multivariable logistic regression models. The STOMA score was developed and internally validated in a cohort of patients operated between 2014 and 2017, with subsequent temporal validation in a 2018 cohort. The discriminative power and calibration of the models' performance were evaluated.Results:This study included 2499 patients with AL, 1954 in the development cohort and 545 in the validation cohort. Baseline characteristics were comparable. One-year stoma-free survival was 45.0% in the development cohort and 43.7% in the validation cohort. The following predictors were included in the STOMA score: sex, age, American Society of Anestesiologist classification, body mass index, clinical M-disease, neoadjuvant therapy, abdominal and transanal approach, primary defunctioning stoma, multivisceral resection, clinical setting in which AL was diagnosed, postoperative day of AL diagnosis, abdominal contamination, anastomotic defect circumference, bowel wall ischemia, anastomotic fistula, retraction, and reactivation leakage. The STOMA score showed good discrimination and calibration (c-index: 0.71, 95% CI: 0.66-0.76).Conclusions:The STOMA score consists of 18 clinically relevant factors and estimates the individual risk for 1-year stoma-free survival in patients with AL after RC surgery, which may improve patient counseling and give guidance when analyzing the efficacy of different treatment strategies in future studies