Quick Release Mechanism Research Articles

A Novel Quick Release Mechanism for Ankle Foot Orthosis Struts.

A posterior dynamic element ankle-foot orthosis (PDEAFO) uses a stiff carbon fibre strut to store and release energy during various mobility tasks, with the strut securely attached to the foot and shank-cuff sections. A design that allows the user to swap struts for specific activities could improve mobility by varying PDEAFO stiffness, but current approaches where bolts securely connect the strut to the orthosis make quick strut swapping time-consuming and impractical. Design a novel quick release AFO (QRAFO) that can enable daily living strut-swapping and thereby enable better ankle biomechanics for the person's chosen activity. The novel QRAFO enables device stiffness changes through a quick release mechanism that includes a quick-release key, weight-bearing pin, receptacle anchor, and immobilization pin. A prototype was modelled and simulated with SolidWorks. Mechanical tests were performed with an Instron 4482 machine to evaluate quick release mechanism strength with running and 20° slope downhill walking loads. Quick release efficiency was then evaluated via two quick release functional tests, with four participants wearing a 3D printed QRAFO. Simulated stress on the weight bearing pin, anchor, and surrounding carbon fibre structure under running and downhill walking loads did not exceed the yielding stress. Mechanical tests verified the simulation results. Four participants successfully swapped the strut within 25.01 ± 3.66 seconds, outperforming the 60.48 ± 10.88 seconds result for the hand-tightened bolted strut. A learning evaluation with one participant showed that, after approximately 30 swapping iterations, swap time was consistently below 10 seconds. The quick release mechanism accommodated running and slope walking loads, and allowed easy and fast strut removal and attachment, greatly reducing strut swap time compared to screw-anchor connections. Overall, the novel quick release AFO improved strut-swapping time without sacrificing device strength, thereby enabling people to use the most appropriate AFO stiffness for their current activity and hence improve mobility and quality of life.

DESIGNING AN UPPER STAGE STEERING SYSTEM FOR A FORMULA FSAE CAR

The objective of this work is to design an upper stage steering system for the Formula FSAE car “Omega” that will effectively translate driver input force to the rack and pinion. The system consists of a steering wheel, steering shafts, universal joints, a quick release mechanism, and connection points to the car. Critical loads have been determined, and the final design has been validated using finite element analysis to ensure the safety of the assembly during normal operation and worst-scenario cases. The design key factors were performance, weight, cost, ergonomics, maintainability, manufacturability and reliability.

Feasibility Study on the Imperatives for the Simulation of Ammonia Release Management

Ammonia is being exported through Bintulu Port via pipeline and loaded to the vessel (ship) using marine loading arm. Ammonia is toxic in nature and transferred at -33 oC. Marine loading arms are special equipment for loading and unloading liquid cargo from the wharf and the vessel with swivel joints, and supplemented by supporting structure, and other accessories. Loading arms have safety features such as that we can set up quick release mechanism, in which the loading arm will decouple from the manifold when there is an emergency, or the movement of vessel is out of range. Studies such as by United Kingdom (UK) Health and Safety Executive (HSE) on loading arm had provided the probabilities of failures, and the possible size of hole such as guillotine break or 0.1 cross sectional area of pipe. This information, with ammonia operational parameters such as internal and external pressure and ammonia liquid flow rate we can thus predict the amount of ammonia release. Combining with meteorological data information, local landscape conditions and utilizing ALOHA software, we are able to simulate ammonia dispersion and thus predicting the impact of toxicity of ammonia release on the population within the area. This paper is a feasibility study that use modelling approaches to manage ammonia leakage.

Experimental research into the effect of gas pressure, particle size and nozzle area on initial gas-release energy during gas desorption

Coal and gas outburst is a violent disaster driven by released energy from gas desorption. The initial expansion energy of released gas (IEERG) is a new method to predict coal and gas outburst. In this paper, an instrument for IEERG measurement was developed. Compared with previous setups, the new one which is equipped with three convergent nozzles and quick-release mechanism gets improved in data acquisition and gas sealing and releasing performance. To comprehensively know the effect of gas pressure, particle size, and nozzle area on IEERG, a series of experiments were carried out with this new setup. The variable control test results indicated that the gas pressure-IEERG curves remain the linear trend and the particle size-IEERG curves maintain the negative exponential trend for nozzle areas at 1.13, 2.26, and 3.39 mm2, respectively. The increase in nozzle area leads to deceases in value of IEERG and absolute value of slope of fitting curves in each test. In addition, the orthogonal experiment showed that the influence of gas pressure, nozzle area, and particle size on IEERG decreases in turn. Only gas pressure had a marked impact on IEERG. This work offers great importance in improving the accuracy of prediction of coal and gas outburst.

Design and evaluation of a modularized ankle-foot orthosis with quick release mechanism.

Ankle foot orthosis (AFO) stiffness affects ankle range of motion but can also provide energy storage and return to improve mobility. To perform multiple activities during the day, a person may want to change their AFO stiffness to meet their activity's demand. Carrying multiple AFOs and changing AFOs is inconvenient and could discourage users from engaging in multiple activities. This project will develop a new quick-release mechanism (QRM) that allows users to easily change posterior strut elements to change AFO stiffness. The QRM attaches to the AFO and requires no tools to operate. The proposed QRM includes a quick-release key, weight-bearing pin, receptacle anchor, and immobilization pin. A prototype was modelled with SolidWorks and simulated with SolidWorks Simulation. The QRM was designed to have no mechanical failure during intense activities such as downhill walking and jogging. Unlike a solid screw connection, the QRM needed an additional part to eliminate unsecured motion related to clearance between the quick release key and receptacle anchor. Mechanical test results and measurement data proved no deformation on each part after mechanical testing.Clinical Relevance- The quick release AFO has the potential to improve user's activities range by tuning from stiffness free mode to high stiffness mode.

Design and Realization of a Robotic Manipulator for Minimally Invasive Surgery With Replaceable Surgical Tools

Minimally invasive surgery is a useful but challenging surgical technique. Several robotic manipulators have been realized in the past three decades to overcome its difficulties. However, a majority of these manipulators lack two important features. First, the ability to provide a right-angled tool entry (with respect to the surrounding skin tissue) for entry-ports located on the far-side of the patient's body, and second, rapid change of the surgical tools. To solve these issues, this article presents synthesis of a new surgical manipulator that ensures a right-angled tool entry—in order to reduce postoperative pain in the patient's skin tissue—through its novel design. We describe the design, perform kinematic analysis, and validate the robotic manipulator's ability to maintain a remote center of motion. The proposed manipulator is equipped with a quick-release mechanism to facilitate rapid change of the surgical instruments during robot-assisted surgery. Contrary to the state-of-the-art, the proposed manipulator does not require extra passive arms to provide a proper tool entry-angle. The manipulator's performance is experimentally evaluated by performing tool-insertion, pegs-transfer, and path-following tasks in a master–slave teleoperation setting. It is demonstrated that the manipulator can perform basic surgical tasks, such as pick-and-place and object manipulation, with a high success rate.

Experiments on the collapse response of flat slab structures subjected to column loss

Flat slab structures are prone to progressive collapse due to their relatively heavy self-weight and susceptibility to punching shear failure. In this study, three one-third scaled slab–column sub-assemblages were statically and dynamically tested to examine the collapse behaviour of such structures when either an edge or a penultimate column is removed. In the static tests, the development of an alternative load path bridging over the removed column was investigated with two specimens that were loaded to failure by a load-control procedure using concrete weights. In the dynamic test, a specimen that had been loaded by concrete weight up to 80% of the yield-line capacity was subjected to a sudden column removal, which was simulated by a quick-release mechanism. Based on the experimental observations, the potential failure modes of flat slab structures, the development of tensile membrane action as an alternative load path, and the dynamic effects resulting from sudden column removal are discussed.

Needle release mechanism enabling multiple insertions with an ultrasound-guided prostate brachytherapy robot.

We present a robotic system for transrectal ultrasound-guided prostate brachytherapy that employs a quick release mechanism to enable multiple needles to be inserted into the prostate prior to plan optimization. The mechanism consists of two actuated fingers that act as needle guides, thereby allowing insertion of both parallel and angled needles. Path planning, including reordering of needles within a batch, is required to avoid collisions with previously inserted needles. We perform two phantom experiments using clinical implant plans. The extra time required for the robotic motions, including finger actuation, is less than three minutes for the entire procedure. Mean position error is measured to be less than 0.5 mm, presumably due to the design of the needle guides, which have a toroidal shape to enable needle angulation.

The effect of short-term isometric training on core/torso stiffness

ABSTRACT“Core” exercise is a basic part of many physical training regimens with goals ranging from rehabilitation of spine and knee injuries to improving athletic performance. Core stiffness has been proposed to perform several functions including reducing pain by minimising joint micro-movements, and enhancing strength and speed performance. This study probes the links between a training approach and immediate but temporary changes in stiffness. Passive and active stiffness was measured on 24 participants; 12 having little to no experience in core training (inexperienced), and the other 12 being athletes experienced to core training methods; before and after a 15 min bout of isometric core exercises. Passive stiffness was assessed on a “frictionless” bending apparatus and active stiffness assessed via a quick release mechanism. Short-term isometric core training increased passive and active stiffness in most directions for both inexperienced and experienced participants, passive left lateral bend among experienced participants being the exception (P < 0.05). There was no difference between the inexperienced and experienced groups. The results confirm that the specific isometric training exercise approach tested here can induce immediate changes in core stiffness, in this case following a single session. This may influence performance and injury resilience for a brief period.

Dynamic Performance of Flush End-Plate Beam-Column Connections and Design Applications in Progressive Collapse

An experimental program was conducted in this study to investigate the dynamic behavior of flush end plate steel beam-column cruciform connections following instantaneous removal of a central supporting column. The dynamic tests were performed by using a quick-release mechanism to simulate sudden column-removal scenarios. In the test program, the geometries of the flush end-plate connections remained unchanged but subjected to five different magnitudes of uniformly distributed load. Another five quasi-static tests were also carried out for comparison with the dynamic response and investigation of the dynamic increase factors (DIF). Test results showed that the release-time durations of the column support force were approximately 30 ms for all five dynamic tests. For the same initial applied dead loads, the maximum dynamic displacement was significantly increased compared to the corresponding quasi-static displacement. In order to observe the full dynamic performance of the tested connection until final failure, a general-purpose finite-element software was used to conduct the three-dimensional numerical simulations. Comparison results showed that the numerical model could accurately simulate the monotonic quasi-static test results and the dynamic test results under sudden column removal. Subsequently, a series of parametric studies was conducted to investigate the connection behavior considering the load-release time, different loading methods, and the magnitude of uniform distributed load. By comparing the full dynamic response of the flush end-plate connection with its corresponding quasi-static response, both the displacement-based DIF and force-based DIF could be respectively determined. The paper also addresses which DIF is more appropriate for the design of structures to resist progressive collapse.

Effect of long-term isometric training on core/torso stiffness.

Although core stiffness enhances athletic performance traits, controversy exists regarding the effectiveness of isometric vs. dynamic core training methods. This study aimed to determine whether long-term changes in stiffness can be trained, and if so, what is the most effective method. Twenty-four healthy male subjects (23 ± 3 years; 1.8 ± 0.06 m; 77.5 ± 10.8 kg) were recruited for passive and active stiffness measurements before and after a 6-week core training intervention. Twelve subjects (22 ± 2 years; 1.8 ± 0.08 m; 78.3 ± 12.3 kg) were considered naive to physical and core exercise. The other 12 subjects (24 ± 3 years; 1.8 ± 0.05 m; 76.8 ± 9.7 kg) were Muay Thai athletes (savvy). A repeated-measures design compared core training methods (isometric vs. dynamic, with a control group) and subject training experience (naive vs. savvy) before and after a 6-week training period. Passive stiffness was assessed on a "frictionless" bending apparatus and active stiffness assessed through a quick release mechanism. Passive stiffness increased after the isometric training protocol. Dynamic training produced a smaller effect, and as expected, there was no change in the control group. Active stiffness did not change in any group. Comparisons between subject and training groups did not reveal any interactions. Thus, an isometric training approach was superior in terms of enhancing core stiffness. This is important since increased core stiffness enhances load bearing ability, arrests painful vertebral micromovements, and enhances ballistic distal limb movement. This may explain the efficacy reported for back and knee injury reduction.

Design and Evaluation of a Novel Self-Locking Quick Release Mechanism Featured by Heavy Load, Fast Response, and High Security

A novel self-locking quick release mechanism featured by heavy load, fast response, and high security is proposed, designed, and evaluated. This new mechanism consists of two release arms, two compression linkages, one control rod, and some revolute joints. The load capability of this mechanism is high up to 15 tons. The characteristics of fast response and high security attributed to structural parameters and the butting-shaped self-locking, respectively, are the essential issues of the mechanism. A 3D model of the proposed mechanism is elaborated for design, evaluation, and simulation purposes. The research also includes the kinematic equations and force analysis to gain insights into the mechanical behavior of the mechanism. The principle of the butting-shaped self-locking is illustrated with the method of virtual work to obtain the critical equilibrium condition while this novel mechanism is not in the ideal position. Finite element method is employed to implement the stress and deformation analysis when the mechanism grasps an object of 15 tons tightly. By fabrication and evaluation of the self-locking quick release mechanism, the validity of the proposed mechanism is proved.

Forensic Engineering Analysis Of A Kite Surfing Accident

The Investigation Of Recreational Accidents Often Involves An Analysis Of Unique Circumstances And Unique Equipment Not Commonly Found In More Traditional Forensic Engineering Investigations. In The Case Of The Kite Surfing Accident Which Is The Subject Of This Paper, It Was Alleged That The Quick-Release Mechanism Failed To Function Properly, Which Caused The User To Be Dragged To A Rocky Shore Causing Injuries. The Engineer Had To Familiarize Himself With The Various Components Of The Kite And Harness System, How The Interaction Of Those Components Under The Control Of The User Led To The Accident, And How The Accident Could Have And Should Have Been Avoided. Conditions Specific To The Subject Accident Were Investigated, Including The User Familiarity With Equipment And Emergency Protocols, Wind Patterns Present At The Time Of The Accident, And Geography Of The Accident Location. Finally, Research Revealed That There Were No Standards Or Regulation Of The Kite Surfing Industry In The United States, But That The Manufacturers Of The Equipment Claimed Compliance With A Foreign Standard. The Equipment Was Then Tested To Determine Whether It Was In Compliance With That Foreign Standard. This Paper Will Address The Proper Operation Of The Kite Surfing Equipment, And Will Describe The Testing That Was Performed By The Engineer To Determine The Effectiveness Of The Quick-Release Component Of The System. It Also Addresses Actions That Were Taken By The User To Attempt Avoidance Of The Accident.

Comparison of 3 Airway Access Techniques During Suspected Spine Injury Management in American Football.

To determine how head movement and time to access airway were affected by 3 emergency airway access techniques used in American football. Prospective counterbalanced design. University research laboratory. Eighteen certified athletic trainers (ATCs) and 18 noncertified students (NCSs). Each participant performed 1 trial of each of the 3 after airway access techniques: quick release mechanism (QRM), cordless screwdriver (CSD), and pocket mask insertion (PMI). Time to task completion in seconds, head movement in each plane (sagittal, frontal, and transverse), maximum head movement in each plane, helmet movement in each plane, and maximum helmet movement in each plane. We observed a significant difference between all 3 techniques with respect to time required to achieve airway access (F2,68 = 263.88; P < 0.001). The PMI allowed for the quickest access followed by the QRM and CSD techniques, respectively. The PMI technique also resulted in significantly less head movement (F2,68 = 9.06; P = 0.001) and less maximum head movement (F2,68 = 13.84; P < 0.001) in the frontal plane compared with the QRM and CSD techniques. The PMI technique should be used to gain rapid airway access when managing a football athlete experiencing respiratory arrest in the presence of a suspected cervical spine injury. In the event the athlete does not present with respiratory arrest, the facemask may be removed carefully with a pocket mask ready. Medical professionals must be familiar with differences in equipment and the effects these may have on the management of the spine-injured athlete.

Field testing of a seismically isolated concrete bridge

The first seismically isolated structure in Taiwan was completed in early 1999. Seven new bridges of the Second National Freeway located at Bai-Ho area, a region which is considered to be of high seismic risk, have been designed and constructed with lead-rubber seismic isolation bearings. Since this is the first application of seismic isolation method to the practical construction in Taiwan, field tests were conducted for one of the seven bridges to evaluate the assumptions and uncertainties in the design and construction. The test program is composed of ambient vibration tests, forced vibration tests, and free vibration tests. For the free vibration tests, a special test setup composed of four 1000 kN hydraulic jacks and a quick-release mechanism was designed to perform the function of push-and-quick release. Valuable results have been obtained based on the correlation between measured and analytical data so that the analytical model can be calibrated. Based on the analytical correlation, it is concluded that the dynamic characteristics and free vibration behavior of the isolated bridge can be well captured when the nonlinear properties of the bearings are properly considered in the modeling.

Pullback Testing of Seismically Isolated P/C I-Girder Bridge

Dynamic testing was performed on a highly skewed, three-span, seismically isolated, prestressed concrete, slab-on-girder bridge. The pullback, quick-release method of testing was used, a first for this bridge type. Several new developments facilitated the quick-release testing. A simple new quick-release mechanism was employed with relatively low lateral test force. Also, a new method of attaching the pullback cable to the bridge was implemented. After testing, a three-dimensional finite element model of the bridge was created. An optimization program was used to refine, or calibrate, the model to match experimentally determined natural frequencies and mode shapes. This automated, systematic optimization of model parameters produced an accurate analytical representation of the bridge. Mode shapes and frequencies from the experimental and analytical investigations are presented.

4938230 Device for selectively producing incremental joint movement in a patient in opposite directions

A device for selectively providing precise incremental joint movement in a patient in either of two opposite directions with a tactile and audible feedback "click", includes first and second spaced disposable retractors for engaging respective parts of the patient adjacent the joint. One of the retractors is mounted on a fixed, inverted, U-shaped support member, and the other retractor is mounted on a movable actuating rod slidably mounted in the support member. The device is formed entirely of non-magnetic material and is readily operable by the patient, making the device especially useful in magnetic resonance imaging procedures. An operating mechanism for the actuating rod includes a pivoted operating handle having an integral drive pawl, and a retaining mechanism for the actuating rod includes a pair of resilient retaining or holding pawls pivoted on the support member adjacent opposite sides of the drive pawl. The operating handle is pivoted on a rockable lifting lever of a retractor quick-release mechanism, so that rocking of the lifting lever raises the handle which, in turn, raises and pivots the holding pawls to release the actuating rod so that it can be readily moved by hand in either of the opposite directions.

Rimless drum structure with tuning device

A rimless drum structure in which a drumhead has a membrane attached to an outer ring and an adjustment ring is disposed beneath the membrane within the outer ring. Tuning devices are spaced around the rings and are adjustable to urge the inner ring against the underside of the membrane, and thereby varying the tension and the tuning of the membrane. Two of such drumheads may be assembled in opposing fashion through the use of a plurality of rigid spacer members attached between the brackets of the upper and lower drumheads. An adjustable snare device having a cam type quick release mechanism and a snare tension adjustment device, may be mounted on the dual headed assembly. Sound control devices having bumpers exerting an adjustable amount of force on the upper drumhead membrane may also be used and these devices may be moved to positions at variable distances from the center of the drumhead to vary the sound effect.

A novel, low-stress eel grader incorporating a quick-release mechanism

Eel farmers frequently grade their stocks according to body size through screens of mesh or parallel bars. Some eels become either entangled or wedged in the screens which may be distorted by the animals themselves, or by the efforts of the operator to free trapped eels. This stresses and can damage the eels, and it reduces the accuracy, and shortens the life, of the grader. Prototype grading equipment was built around a novel design of tapered grading slat which (a) prevented eels up to 240 g live weight from becoming entangled, and (b) allowed the rapid release of eels that had become wedged between the grading slats. Tests showed the principles of the design to be suitable for use in or out of water and with all sizes of eel from 0·5 to 240 g live weight.

A Restraint and Transillumination Device for Neonatal Arterial/Venipuncture: Efficacy and Thermal Safety

A different method of restraint together with technical details for construction demonstrating the use of reflected high intensity fiberoptic light is presented. Thermal data are presented demonstrating safety within recognized biologic skin temperature safety which permits utilization of a high intensity See Images in the PDF File light source for arterial or venous cannulation for prolonged periods of time extending to 20 minutes. This device presents a method to demonstrate visualization of blood vessels in the infant's extremity without risk of thermal burn associated with an adequate flexible restraint quick-release mechanism. Disposable polyurethane 5-mm pads (cut from sheets) were utilized to minimize pressure on bony prominences or nerves of the extremity. Neither thermal burns nor pressure alterations have been noted. Although not specifically evaluated, the use of a heat filter and CS-2-73 orange filter might further reduce heat buildup while using this device.