Tail Rope Research Articles

Adaptive boundary control for a friction hoisting system during the loading process

This paper aims at the rope dynamic tension fluctuation (DTF) control in the friction hoisting system (FHS) during the loading process. The exact dynamic modelling of the tail and head ropes connected to the cage is considered. A disturbance observer is proposed to track the actual impact disturbance. The actuator acts at the friction wheel to pretension the system. The use of an adaptive neural network allows for the handling of system uncertainty. An appropriate control law is developed to stabilize the cage and suppress the rope DTF in FHS during the loading process. Numerical simulations and theoretical analysis are presented to prove the feasibility and effectiveness of the proposed control law. Numerical analysis results show that the head rope dynamic displacement fluctuation (DDF) and DTF amplitudes can be suppressed to at least 1/125 of their initial fluctuation amplitudes under the proposed control law.

Visual Recognition Method for Lateral Swing of the Tail Rope

The large lateral displacement of tail ropes increases the risk of their wear and fracture, posing hidden dangers to the safety of the hoisting system. However, no suitable method is available to recognize the lateral swing of tail ropes online. A target-free visual measurement method, which includes the dual-branch SiamSeg, was proposed in this study. Considering the slender characteristics of tail ropes, the receptive field of the feature extraction network was enhanced via the Receptive Field Module (RFM), thereby strengthening the discriminability and integrity of tail rope features. The consistency loss constraints were added to the segmentation loss function to maximize the time sequence information of the video and further improve the accuracy of pixel-level displacement. Compared with other methods, the proposed approach achieved better segmentation effects. Comparison results synchronously measured by sensors revealed the effectiveness of this method and its potential for practical underground applications.

Equipment‐related injuries associated with head and tail rope recovery in horses

No conflicts of interest have been declared.

Coccygeal vertebral damage in a multiparous mare following head and tail rope‐assisted recovery from general anaesthesia

SummaryAn 18‐year‐old multiparous Thoroughbred mare with a 2‐month‐old foal at foot presented for investigation of colic. A right dorsal displacement of the large colon with a retroflexion of the pelvic flexure was corrected under general anaesthesia and interventional recovery using head and tail ropes was performed. The mare made multiple attempts to stand, using the ropes for support before achieving and maintaining a standing position. The following day, marked swelling around the perineal and vulval region was noted, combined with reduced tail tone. Urination, but not defaecation, had been observed following surgery. Transrectal ultrasonography indicated formation of a haematoma adjacent and ventral to the caudal sacral and first coccygeal vertebrae. Initial radiographic evaluation was suggestive of an oblique fracture of the caudal endplate of the first coccygeal vertebra, which was confirmed on repeat radiography 7 days later. Treatment included cold compresses to reduce swelling, multimodal analgesia, dietary modification to soften faecal consistency and regular manual evacuation of the rectum to avoid impaction. The mare was discharged after 19 days hospitalisation, gradually recovered the ability to defaecate and produced a viable foal the following year without assistance.

Optimizations of the internal structure of the reel of a double rope winder

Due to the shortage of resources, the deep development of resources is imminent, and the superdeep mine hoist plays a leading role in the development process. According to the structure, the hoists can be divided into winding hoists and friction hoists. Winding hoists can be single-rope winding and multirope winding. With the increase of mining depth, friction hoists will have the disadvantage of increasing the mass of the tail rope, while wire rope diameter of single-rope winding hoists will increase with the increase of mining depth. So double-rope winding hoists can be used to balance the above two problems. Therefore, this study will use finite element analysis, and treat hoist reel as a uniformly pressurized shell, through the static and modal analysis of reel. Under the maximum static tension, this study gets the reel the force and deformation distribution. Through the change of the internal structure of the reel, it improves the reel force weakness and reduce the reel deformation. By reducing the deformation of the reel, this study tells how to reduce the tension difference of the wire rope. This study will improve the synchronization and stability of the hoisting system and provide an alternative and effective way for the deep development of the resources with the double-rope winding hoists.

Study on fault diagnosis method for the tail rope of a hoisting system based on machine vision

Healthy operation of the tail rope is crucial to the stable and safe operation of a friction hoisting system. Failure of the tail rope will threaten the property and personnel. In this study, a fault diagnosis algorithm based on deep learning is proposed for the tail rope. Specifically, we add a spatial attention mechanism in the feature extraction stage to assign different weights to different regions in images. This way “guides” the model to focus on more important regions. A class-balance cross-entropy loss is introduced to alleviate the imbalanced data distribution in the actual conditions for enhancing the robustness of the algorithm and its transferability in practical applications. Experimental studies are conducted to validate the algorithm. The accuracy of the algorithm on the conducted dataset is 99.4819%. The accuracy of the provided algorithm is increased by 10% and 7% compared with those of the hand-crafted features, namely, scale-invariant feature transform with support vector machine and random forest, respectively. Results show that the proposed algorithm can meet the requirements of high accuracy and generalization in practical engineering applications.

Head and tail rope-assisted recovery improves quality of recovery from general anaesthesia in horses undergoing emergency exploratory laparotomy.

In equine anaesthesia, the recovery period is critical, accounting for most anaesthesia-related fatalities reported. Horses may recover unassisted or may be assisted, for example, using a head and tail rope recovery method. To compare the impact of head and tail rope and unassisted recovery method on quality of recovery in horses undergoing colic surgery under general anaesthesia (GA). Single centre retrospective cross-sectional study, with prospective model performance analysis. Clinical data were obtained from horses undergoing emergency exploratory laparotomy over a 6-year period. Multivariable logistic regression analysis was used to identify the perioperative factors that affect quality of recovery. The final prediction model was assessed prospectively. Records from 502 general anaesthetics (490 horses) were included. Multivariable logistic regression analysis showed that head and tail rope recovery (OR 2.2, 95% CI 1.4-3.3, P<.001) and sevoflurane administration (OR 1.6, 95% CI 1.2-2.3, P=.02) were associated with better quality of recovery when compared with unassisted recovery and isoflurane administration respectively. Increasing GA duration (OR 1.0, 95% CI 0.99-1.0, P=.03), increasing intraoperative dosages (in mg/kg) of thiopental (OR 0.85, 95% CI 0.75-0.98, P=.02) or ketamine (OR 0.67, 95% CI 0.46-0.99, P=.04) were linked to poor quality of recovery. No statistically significant difference was found between recovery groups in terms of mortality. The clinical prediction model obtained is only applicable to the specific facilities, recovery methodology, referral population and anaesthetic protocols practiced at our institution. Head and tail rope recovery is significantly associated with better quality of recovery, compared with unassisted recovery, in horses undergoing emergency exploratory laparotomy. Sevoflurane administration, in detriment of isoflurane, was associated with better quality of recovery. Other risk factors, such as increasing GA duration, the use of higher intra-operative dosages of ketamine and/or thiopental, were associated with poor quality of recovery.

The effects of flumazenil on ventilatory and recovery characteristics in horses following midazolam-ketamine induction and isoflurane anaesthesia.

Flumazenil antagonises the actions of benzodiazepines. There has been no prior research specifically investigating this anaesthetic reversal agent for horses. To determine the effects of flumazenil administration in horses on (a) ventilatory parameters after midazolam-ketamine induction and maintenance with isoflurane in oxygen and on (b) the characteristics of recovery from general anaesthesia. Blinded, randomised, crossover experiment. Six horses were randomly assigned to receive high-dose flumazenil (Fhigh , 20µg/kg), low-dose flumazenil (Flow , 10µg/kg) and saline (control). Cardioventilatory parameters were monitored. After 90minutes of isoflurane anaesthesia, a bolus of Fhigh , Flow or saline was administered i.v. The horses were recovered using head and tail rope assistance. The times to first movement, to achievement of sternal recumbency, to the first attempt to stand and the total recovery time were determined. The recovery quality was evaluated using a 115-point recovery scoring system. The cardioventilatory parameters and recovery times were analysed using mixed-effects regression analyses. Intraclass correlation (ICC) analysis was used to evaluate the recovery scores. A Mann-Whitney U test assessed the relationship between recovery score and flumazenil administration. A significant difference with flumazenil administration was found for SpO2 , mean arterial pressure, I:E ratio, minute volume of ventilation (MV) and peak inspiratory pressure. There was a significant difference with flumazenil administration for the time to sternal recumbency, the time to the first attempt to rise and the total recovery time. There was no significant difference in total recovery score with flumazenil administration. Plasma levels of midazolam and flumazenil were not obtained. Flumazenil has a dose-dependent effect on MV and recovery time, which may make it useful in cases for which a prolonged anaesthetic recovery is undesirable.

Effect of head and tail rope‐assisted recovery of horses after elective and emergency surgery under general anaesthesia

SummaryThe recovery phase is a critical period during equine anaesthesia. In an attempt to reduce the risk of recovery, several recovery systems, including head and tail ropes, have been developed over time. However, the clinical safety and efficacy of these systems have not been compared to a nonassisted group in a larger study. The objective of this comparative, retrospective, nonrandomised single‐centre study was to determine whether the risk of developing fatal and nonfatal complications after general anaesthesia is reduced in horses assisted with head and tail ropes during recovery compared with horses recovering unassisted. Included were all horses undergoing general anaesthesia at the Large Animal Hospital, University of Copenhagen, Denmark, from 2010 to 2019. Analysed data included age, body mass, American Society of Anesthesiologists grade of physical status (ASA score), type of surgery and anaesthetic duration. Complications were divided into none, fatal and nonfatal. Logistic regression was performed to analyse the risk and predictors of fatal and nonfatal complications using the built‐in R function ‘step’. Tukey’s honest significance difference test was applied to determine significance, set at P&lt;0.05, within the categorical variables of the reduced models. The study included 1252 horses: 662 recovered with assistance (group A) and 590 without (group NA). Overall recovery‐associated mortality was 1.4%: 0.6% in group A and 2.2% in group NA. Both emergency abdominal surgery (P = 0.004) and duration of surgery (P = 0.0001) affected the risk of fatal complications negatively. Assisted recovery (P = 0.02) significantly reduced the risk of fatal complications after emergency abdominal surgery. The limitation of the study was a lack of randomisation and potentially a larger proportion of sedation among assisted horses. It was concluded that emergency abdominal surgery and duration of anaesthesia are significant risk factors for fatal complications during recovery. Head and tail rope‐assisted recovery is a significant factor of reducing fatal complications during recovery after emergency abdominal surgery.

A Bevel Gear Tension Balancing Device for Mining Hoist

Background:: With the increasing mining depth, single rope winding hoist and multi-rope friction hoist may not be feasible in ultra-deep wells. For the single rope winding hoist, larger rope diameter and drum diameter are required, while a lot of inconveniences would arise in the manufacturing process. For the multi-rope friction hoist, the balance tail rope is necessary so that a fluctuation in stress greater than 11.5% of the wire rope breaking force increases. Objective:: The purpose of this patent is to provide an overview of a tension balancing device using new bevel gear system in the multi-rope winding hoist. In the research, varying tension of the rope winded on each drum is conveniently and quickly adjusted in different working conditions. Methods:: A bevel gear balancing device is designed in the multi-rope winding hoist. It mainly consists of big and small output bevel gear, shell, balance bevel gear, and support frame. Results:: Unbalanced tension caused by different lengths of the ropes is compensated without any restrictions. The tension of all wire ropes is always in balance ensured by the balancing mechanism throughout the whole process of lifting and lowering containers. When the winding diameter of the drums is different, the tension of the hoisting-ropes will not be precisely adjusted. But it can be negligible. Conclusion:: The bevel gear balancing device in the patent is installed on the main shaft of the multirope winding hoist. Through analysis, the device was observed to be simple and easy to operate. The tension of the hoisting-ropes can be accurately balanced.

Central blindness following general anaesthesia due to suspected catheter-related venous air embolism in a gelding

This case report describes a transient post-anaesthetic bilateral central blindness caused by suspected air embolism associated with intravenous catheter cap disconnection and its medical management in a horse. The cap...

Health Monitoring for Balancing Tail Ropes of a Hoisting System Using a Convolutional Neural Network

With the arrival of the big data era, it has become possible to apply deep learning to the health monitoring of mine production. In this paper, a convolutional neural network (CNN)-based method is proposed to monitor the health condition of the balancing tail ropes (BTRs) of the hoisting system, in which the feature of the BTR image is adaptively extracted using a CNN. This method can automatically detect various BTR faults in real-time, including disproportional spacing, twisted rope, broken strand and broken rope faults. Firstly, a CNN structure is proposed, and regularization technology is adopted to prevent overfitting. Then, a method of image dataset description and establishment that can cover the entire feature space of overhanging BTRs is put forward. Finally, the CNN and two traditional data mining algorithms, namely, k-nearest neighbor (KNN) and an artificial neural network with back propagation (ANN-BP), are adopted to train and test the established dataset, and the influence of hyperparameters on the network diagnostic accuracy is investigated experimentally. The experimental results showed that the CNN could effectively avoid complex steps such as manual feature extraction, that the learning rate and batch-size strongly affected the accuracy and training efficiency, and that the fault diagnosis accuracy of CNN was 100%, which was higher than that of KNN and ANN-BP. Therefore, the proposed CNN with high accuracy, real-time functioning and generalization performance is suitable for application in the health monitoring of hoisting system BTRs.

A retrospective report (2003\u20132013) of the complications associated with the use of a one-man (head and tail) rope recovery system in horses following general anaesthesia

BackgroundThe mortality rate of horses undergoing general anaesthesia is high when compared to humans or small animal patients. One of the most critical periods during equine anaesthesia is recovery, as the horse attempts to regain a standing position. This study was performed in a private equine practice in Belgium that uses a purpose-designed one-man (head and tail) rope recovery system to assist the horse during the standing process.The main purpose of the retrospective study was to report and analyse complications and the mortality rate in horses during recovery from anaesthesia using the described recovery system. Information retrieved from the medical records included patient signalment, anaesthetic protocol, duration of anaesthesia, ASA grade, type of surgery, recovery time and complications during recovery. Sedation was administered to all horses prior to recovery with the rope system. Complications were divided into major complications in which the horse was euthanized and minor complications where the horse survived. Major complications were further subdivided into those where the rope system did not contribute to the recovery complication (Group 1) and those where it was not possible to determine if the rope system was of any benefit (Group 2).ResultsFive thousand eight hundred fifty two horses recovered from general anaesthesia with rope assistance. Complications were identified in 30 (0.51%). Major complications occurred in 12 horses (0.20%) of which three (0.05%) were assigned to Group 1 and nine (0.15%) to Group 2. Three horses in Group 2 suffered musculoskeletal injuries (0.05%). Eighteen horses (0.31%) suffered minor complications, of which five (0.08%) were categorised as failures of the recovery system.ConclusionsThis study reports the major and minor complication and mortality rate during recovery from anaesthesia using a specific type of rope recovery system. Mortality associated with the rope recovery system was low. During recovery from anaesthesia this rope system may reduce the risk of lethal complications, particularly major orthopaedic injuries.

Reduction and external coaptation as successful treatment for tarsocrural joint luxation in an Arabian mare

SummaryA 4‐year‐old Arabian mare was presented for evaluation of a suspected right tarsal luxation. Radiographs of the affected area revealed a tarsocrural joint luxation with an associated fractured lateral tibial malleolus. Under general anaesthesia, the fractured lateral malleolus was surgically removed via an arthrotomy and the luxation reduced. A full‐limb fibreglass cast was then placed. Recovery from anaesthesia was assisted with a tail rope. The limb was immobilised for 8 weeks with a cast. The mare made a good recovery and was used as a broodmare 18 months later, despite osteoarthritis affecting the joint.

Depth Enhancement of an Underwater Towed System using Hydrodynamic Depressor

&lt;p&gt;The underwater towed system described here consists of tow cables, a towed body, an acoustic module and tail rope towed behind a surface ship. The required depth at a particular speed of the towing ship is obtained by paying out specified length of cable from the winch. However the excessive drag forces on the various components of the towed system results in impractically large values of cable length, especially at higher speeds. A hydrodynamic depressor is designed to improve the depth performance. The design is evolved based on numerical analysis and towing tank tests. Estimation of depth attained is carried out based on steady state theory of tow cables. Validation of the numerical analysis results is carried out through field evaluation of depressor performance during sea trial of the towed system.&lt;/p&gt;

Loads Acting on the Mine Conveyance Attachments and Tail Ropes during the Emergency Braking in the Event of an Overtravel

Abstract It has now become the common practice among the design engineers that in dimensioning of structural components of conveyances, particularly the load bearing elements, they mostly use methods that do not enable the predictions of their service life, instead they rely on determining the safety factor related to the static loads exclusively. In order to solve the problem, i.e. to derive and verify the key relationships needed to determine the fatigue endurance of structural elements of conveyances expressed in the function of time and taking into account the type of hoisting gear, it is required that the values of all loads acting upon the conveyance should be determined, including those experienced under the emergency conditions, for instance during the braking phase in the event of overtravel. This study relies on the results of dynamic analysis of a hoisting installation during the braking phase when the conveyance approaches the topmost or lowermost levels. For the assumed model of the system, the equations of motion are derived for the hoisting and tail rope elements and for the elastic strings. The section of the hoisting rope between the full conveyance approaching the top station and the Keope pulley is substituted by a spring with the constant elasticity coefficient, equal to that of the rope section at the instant the conveyance begins the underwind travel. Recalling the solution to the wave equation, analytical formulas are provided expressing the displacements of any cross-profiles of hoisting and tail ropes, including the conveyance attachments and tail ropes, in the function of braking forces applied to conveyances in the overtravel path and operational parameters of the hoisting gear. Besides, approximate formulas are provided yielding: –loading of the hoisting rope segment between the conveyance braking in the headgear tower and the Keope pulley –deceleration of the conveyance during the braking phase. The results will be utilised to derive the function governing the conveyance load variations during the emergency braking, depending on the parameters of the hoisting installations and the braking systems. These relationships are required for adequate design of the frictional contact between the ropes and the pulley and will become the basic criteria for dimensioning and design of load-bearing components of conveyances in the context of improving their reliability and safety features.

Comparison of non-assisted versus head and tail rope-assisted recovery after emergency abdominal surgery in horses

The objective of this study was to compare anaesthetic recoveries without assistance (group NA) to a head and tail rope-assisted technique (group A) after emergency abdominal surgery in horses. Additionally, possible risk factors for the quality of recovery (S: safe, NS: non-safe) were investigated and possible complications associated to the head and tail rope technique recorded. For that purpose 200 anaesthetic protocols (100NA, 100A) from horses that all received a standardised medetomidine-isoflurane balanced anaesthesia regime and medetomidine in combination with morphine for recovery were analysed retrospectively. No significant difference regarding recovery score was detected between NA and A horses. Fatalitalities (3/100 in each group) were similarly distributed between groups. However, in group NA only one horse died because of trauma during recovery. The other two horses died before attempting to stand up. All 3 horses that died in group A were euthanized because of trauma. Hypoxemia (defined as arterial oxygen partial pressure <60mmHg) during anaesthesia was a risk factor for non-safe recoveries. No influence was detected for age, weight, duration of general anaesthesia, reason of colic surgery, recovery technique (A, NA), hypotension during anaesthesia, time in lateral recumbency, time in sternal recumbency and time until standing. Several technical complications (material fail, twisting of ropes, halters slipping off and loss of ropes) were observed using the head and tail ropes, probably being partially responsible for the unexpectedly high number of dangerous and fatal recoveries observed in group A. The present study could not demonstrate that the head and tail rope technique can reduce fatalities or improve anaesthetic recovery scores after emergency abdominal surgery in horses. Hypoxemia during general anaesthesia increases the risk of non-safe recovery.

Design and Development of Depth Activated Inflatable Recovery System for Undersea Towed Sensor Arrays

A typical towed sensor arraywet-end system consists of electro optic-mechanical tow cables, active transmitter unit and towed sensor array modules followed by a tail rope at the aft-end. The sensor array and cables are designed to withstand harsh marine environment and hydrodynamic forces experienced due to waves and currents during operation. Nevertheless, the strength member termination in the tow cable and array are vulnerable to failure due to dynamic loading during repeated deployment and retrieval operations.To prevent the loss of cable and array in such cases, a recovery system is required. In this paper, the design of a Depth Activated Inflatable Recovery System for undersea towed sensor arrays is presented. The envisaged system is a cylindrical, flexible module with similar diameter as the sensor array module and maximum length of 10 m which can be mechanically attached to the aft-end of the towed array. The system consists of a pressure switch, which gets activated as the detached array sinks and reaches a pre-set depth of 250 m. This completes an electrical circuit connected to a power source through which high current passes to an electro-explosive pyro-cartridge and activates it. This generates enough force to push a piston mechanism which punctures a CO2 cylinder. The CO2 gas fills into an inflatable bag. Multiple numbers of such inflatable bags, when opened, will provide sufficient buoyancy for array to move up to the surface. The paper discusses the design methodology, development, assembly and testing of various sub-systems, challenges faced and innovative solutions implemented for realizing an effective Recovery System.

A study of the correlation between objective and subjective indices of recovery quality after inhalation anaesthesia in equids

ObjectiveTo examine the association between objective and subjective descriptors used for assessing recovery quality in horses after anaesthesia. Study designProspective clinical study. AnimalsTwo hundred and seventy–six equids (110 mares, 85 entire males and 81 geldings), ASA 1–5, weighing 50–850 kg and aged 1 month – 25 years. MethodsRecoveries after general anaesthesia were assisted with head and tail ropes by two anaesthetists. One scored dichotomous objective descriptors (DOD) of recovery. Two dichotomous objective scales (DOS) were then generated from those descriptors. The same individual also scored overall recovery quality using a visual analogue scale (VAS). The second anaesthetist scored recovery (good or bad) using a dichotomous subjective scale (DSS). Each DOD, the DSS and VAS were compared with each other using Pearson’s chi–square test. DOSs were compared to the DSS using Wilcoxon’s test and to the VAS using a Spearman’s correlation test. ResultsMost DODs were associated (p < 0.05) with DSS and VAS. The DSS was not associated with resting/not resting in sternal recumbency (p = 0.535) nor with the time spent in sternal recumbency (p = 0.09). VAS and DSS scores were strongly associated (p < 0.0001). The two DOSs were in agreement with DSS (p < 0.0001) and negatively correlated to VAS (r12 = 0.38, r22 = 0.34, respectively, p–value <0.0001). ConclusionObjective descriptors were linked closely with the subjective evaluations of recovery quality except for the presence or absence of a sternal recumbency phase and its duration. Clinical relevanceThese components may not be essential in recovery scoring systems. The DOS were in agreement with DSS and VAS and could be a useful tool for further studies on recoveries.

Lateral stiffness and deflection of vertical ropes with application to mine shaft hoisting

The use of vertically hanging wire ropes is one method of guiding mine shaft conveyances as they travel up and down the shaft. These ropes provide restoring forces to the conveyances as they deviate laterally from their intended vertical paths under the influence of imposed loads due to aerodynamic, Coriolis and rope torque effects. The design of rope guided systems has proceeded rather empirically, supported by industry rules of thumb that lack a fundamental engineering mechanics basis. This paper addresses part of the lack of fundamental information by analytically developing the deflected shapes of a hanging rope when acted on by lateral point and distributed loads. This analysis proceeds from the governing differential equation of equilibrium for an element of the rope. Throughout the paper, the development is applied to rope guided conveyance systems. However, the solutions developed are general and could be applied to other situations. The deflected shape of a guide rope to a laterally applied point load is given and the influence of the guide rope tensioning, as well as the point of load application is demonstrated. Relationships for guide rope lateral stiffness and flexibility are derived, which also demonstrate the influence of guide rope tensioning, as well as the linear density of the rope. The extent to which the hoist rope on a conveyance deflects under lateral loads applied at the conveyance is also analysed leading to useful deflected shape, stiffness and flexibility relationships. Finally, the distributed lateral (Coriolis) loading on the travelling hoist and tail ropes are considered, leading to the derivation of deflected shapes of both the head and tail rope, as well as the equivalent forces acting at the conveyance.