Dynamic Maneuvers Research Articles

Isolated partial tear of extensor digitorum longus tendon with overlying muscle herniation in acute ankle sports injury: role of high resolution musculoskeletal ultrasound

Lateral Ankle sprain is a common sports-related trauma with the mechanism of injury ranging from inversion to plantar flexion. These injuries commonly affect the ligaments but can also affect the associated soft tissue structures like the eversion muscles and tendons. Prompt and accurate diagnosis of such injuries is warranted so as to ensure early return to play and prevent long-term complications. Lateral ankle sprain injuries in sports may not always be associated with ligament injuries. We report a never before reported case of lateral ankle sprain injury in a soccer player with the unusual finding of isolated partial tear of Extensor digitorum longus muscle and its fascia leading to myo-fascial herniation. The lateral ankle ligaments were intact. The diagnosis was clinched on a high-frequency ultrasound scan supported by dynamic maneuvers which in fact proved to be superior to MRI as the latter failed to demonstrate the myo-fascial herniation in our case. We therefore propose that real-time ultrasound scanning with dynamic maneuvers should be the first line of investigation to assess sports injuries in anatomically complex joints like the ankle.

Dynamically Feasible Task Space Planning for Underactuated Aerial Manipulators

In this work, we address the problem of planning dynamically feasible trajectories for underactuated aerial manipulators to achieve a desired trajectory for the end effector. We consider a quadrotor equipped with an arbitrary n-joint articulated arm. We show that the combined underactuated system is differentially flat, however the flat outputs do not correspond directly to the motion of the end effector. We therefore develop a method which determines the family of flat output trajectories which will exactly produce any desired task trajectory, even in the case of dynamic maneuvers. We also give criteria on the manipulator geometry which will ensure certain important stability properties, informing hardware design. The entire approach is demonstrated in simulation for systems of varying geometry and number of joints. The simultaneous resolution of the kinematic and dynamic constraints allows these tasks to be performed dynamically without sacrificing accuracy.

Implicit coordination for 3D underwater collective behaviors in a fish-inspired robot swarm.

Many fish species gather by the thousands and swim in harmony with seemingly no effort. Large schools display a range of impressive collective behaviors, from simple shoaling to collective migration and from basic predator evasion to dynamic maneuvers such as bait balls and flash expansion. A wealth of experimental and theoretical work has shown that these complex three-dimensional (3D) behaviors can arise from visual observations of nearby neighbors, without explicit communication. By contrast, most underwater robot collectives rely on centralized, above-water, explicit communication and, as a result, exhibit limited coordination complexity. Here, we demonstrate 3D collective behaviors with a swarm of fish-inspired miniature underwater robots that use only implicit communication mediated through the production and sensing of blue light. We show that complex and dynamic 3D collective behaviors-synchrony, dispersion/aggregation, dynamic circle formation, and search-capture-can be achieved by sensing minimal, noisy impressions of neighbors, without any centralized intervention. Our results provide insights into the power of implicit coordination and are of interest for future underwater robots that display collective capabilities on par with fish schools for applications such as environmental monitoring and search in coral reefs and coastal environments.

A New Triple Filtering Algorithm and Its Application for Aerial GNSS/INS‐Integrated Direct Georeferencing System

A global navigation satellite system and inertial navigation system‐ (GNSS/INS‐) integrated system is employed to provide direct georeferencing (DG) in aerial photogrammetry. However, GNSS/INS suffers from stochastic error, strong nonlinearity, and weak observability problems in high dynamic or less maneuver scenarios. In this paper, we proposed a new triple filtering algorithm for aerial GNSS/INS integration. The new algorithm implements filtering in the sequence of forward, backward, and forward directions. Each filter is initialized by a previous filter to get a quick convergence, and the final result is combination of the last two filtering to smooth error. The proposed triple filtering strategy avoids inaccuracy in the 1st forward filtering when the system has not reached convergence. Moreover, it facilitates engineering implementation because backward filtering can employ the same equations with forward filtering. To assess stochastic error of the inertial measurement unit, the Allan variance method is used and abbreviated stochastic model is built. A real aerial testing is conducted, and the result indicates that DG can achieve horizontal accuracy of 5 cm by the proposed algorithm, which has 63% improvement compared to standard extended Kalman filter.

Static and Dynamic Pressure Measurement in Flight Test Application With Optical Fabry–Pérot Sensors

Conventional electrical pressure sensors show degradation of their performance in harsh environments because of their low overload protection, drawn back membrane, susceptibility to electromagnetic influences, and corrosion. Fiber-optic measurements overcome those challenges and promise to be a robust sensing solution for vigorous flight testing. We developed a passive fiber-optic Fabry-Pérot pressure sensor with a minimum thickness of 1.6 mm, natural frequency above 250 kHz, linear transfer characteristic, burst pressure resistance above >30 times full-scale, and without conductive corrosive materials. It can measure aerostatics, aerodynamics, and aeroacoustics down to 70-dB SPL. In combination with an industrialized edge filter measurement device, the fiber-optical sensor's simplified instrumentation is demonstrated on a microlight aircraft, performing dynamic maneuvers. The measurement data of near-stall flight situations demonstrate the monitoring capabilities of detached airflow in harsh environments.

A Hybrid Data Fusion Approach to AI-Assisted Indirect Centralized Integrated SINS/GNSS Navigation System During GNSS Outage

The main challenges for integration between low-cost strap-down inertial navigation system (SINS) and global navigation satellite system (GNSS) are to manage the non-Gaussian measurement noises and to access the reliable measurements during GNSS outages. Therefore, in this paper, some approaches are taken in the proposed integrated navigation system: (1) using an iterative empirical mode decomposition (EMD) interval thresholding de-noising method for low-cost inertial measurements to provide smoother and more accurate SINS measurements with less complexity, (2) designing an enhanced indirect centralized correntropy Kalman filter using a novel fuzzy parameter adjustment approach, which adaptively changes the estimation algorithm parameters to further improve the robustness of the proposed algorithm in the presence of dynamical maneuvers and non-Gaussian measurement noise, and (3) utilizing a pre-filtered nonlinear autoregressive network with exogenous inputs (PFNARX) designed to provide reliable interrupted positioning information during GNSS outages. The proposed SINS/GNSS system is experimentally evaluated through real-world flight tests. The obtained results reveal that the designed integration algorithm remarkably improves the estimation accuracy by adaptively tuning the parameters in an improved correntropy Kalman filter and an efficient and well-trained artificial neural network-based model in the absence of GNSS signal.

LPV/LFT Control Design Equipped with a Command Governor for Different Steering Scenarios

Abstract This paper presents a Linear Parameter Varying (LPV) based approach to handle different steering scenarios for autonomous vehicles. The proposed methodology consists of the design of a fast and performant LPV/LFT controller which can track the generated yaw rate reference, for speed operating range, for lane tracking and smooth/fast lane changes. The handling of a dynamic maneuver is achieved by a Command Governor (CG), which feeds the updated LPV/LFT closed loop system with a “virtual” yaw rate reference. This virtual signal is the solution of an online receding horizon optimization problem, meeting simultaneously safety bounds for the steering of the vehicle. The efficiency of the suggested methodology is illustrated by simulation results for parameters of an automated Renault Zoe.

Arterial hypertension and cerebral hemodynamics: impact of head-down tilt on cerebral blood flow (arterial spin-labeling-MRI) in healthy and hypertensive patients.

Hypertension affects cerebrovascular autoregulation and increases the risk of cerebrovascular events and dementia. Notably, it is associated with cerebrovascular remodeling and lower resting cerebral blood flow (CBF). We wanted to determine, using arterial spin-labeling-MRI, the impact of a head-down tilt (HDT) dynamic maneuver on CBF in hypertensive patients. The current prospective study measured 36 patients' CBFs (18 normotensive individuals; 18 hypertensive patients) on 1.5T arterial spin-labeling-MRI in the supine position and after 4 min at -15° HDT. We reconstructed CBF maps of left and right subcortical nuclear gray matter, cortical gray matter and white matter (16 structures) to explore cerebrovascular autoregulation modification under dynamic conditions. Normotensive and hypertensive participants had no significant CBF differences in the supine position. After HDT, CBF mean variations (CBF-mVs) across all structures declined (mean -5.8%) for the whole population (n = 36), with -6.6 and -7.6% decreases, respectively, in white matter and gray matter (P < 0.001). Left and right accumbens nuclei had the largest changes (-9.6 and -9.2%, respectively; P < 0.001). No CBF-mV difference (0/16) was found in hypertensive patients after HDT, whereas normotensive participants' CBF-mVs changed significantly in four structures (left and right accumbens, putamen and left caudate nucleus) and gray matter. Hypertensive patients exhibited fewer CBF-mVs in left caudate nuclei (P = 0.039) and cortical gray matter (P = 0.013). Among hypertensive patients, people with diabetes had smaller CBF-mVs than people without diabetes. Our results highlight the significantly different CBF reactions to HDT of normotensive and hypertensive participants. They support the hypothesis that hypertension is responsible for deficient cerebrovascular autoregulation.

Extended Object Tracking Using Spatially Resolved Micro-Doppler Signatures

Recent progress in radar development enable high-resolution radar sensors to resolve multiple detections for an extended object. One of the main challenges in radar-based object detection and tracking is the handling of an uncertain measurement model problem dealing with wandering dominant scatter points on the extended object surface depending on the relative orientation and motion. This phenomenon needs to be considered for near extended object tracking in critical driving situations, e.g., for safety applications, which require fast and accurate target state estimation in high dynamic scenarios. This paper presents a method to detect rotating wheels of approaching targets. Using the position and velocity of detected wheels as input for a tracking procedure, instead of target detections, relaxes the uncertain measurement model problem. A generic radar signal processing method to detect the position and bulk velocities of rotating wheels for approaching target vehicles is presented. The method evaluates the micro-Doppler signals, generated by rotating wheels, of close targets. These wheel hypotheses serve as input for a subsequent sequential Monte Carlo tracking framework. The presented methods are evaluated on real experimental data where a target vehicle is used to reconstruct safety-critical dynamic evading maneuvers.

Medial Ankle Stability Evaluation With Dynamic Ultrasound: Establishing Natural Variations in the Healthy Cohort.

Destabilizing injuries to the deltoid ligament have relied on radiographic stress examination for diagnosis, with a focus on medial clear space (MCS) widening. Recently, studies have demonstrated the use of ultrasonography to assess deltoid ligament injury, but not the medial ankle stability. The purpose of this study was to assess the MCS via ultrasonography while weight-bearing and with a gravity stress test (GST) in the uninjured ankle as a means of establishing normative values for future comparison. Twenty-six participants with no reported ankle injury in their premedical history were included. The MCS was examined using ultrasonography with the patient lying in a lateral decubitus position to replicate a GST with the ankle held in a neutral and plantarflexed position as well as while weight-bearing. The MCS was assessed in mm at the anteromedial and inferomedial aspect of the ankle joint. With weight-bearing, the average anterior MCS and inferior MCS were 3.6 and 3.3 mm, respectively. During the GST in neutral ankle position, the average anterior MCS was 4.1 mm, whereas the average inferior MCS was 4.0 mm. When measured during the GST in plantarflexed ankle position, the averages anterior MCS and inferior MCS increased to 4.4 mm. MCS values were notably higher with GST than with weight-bearing measurements (P < 0.001). MCS values were notably higher with the foot in a plantarflexed compared with a neutral position when doing GST (P < 0.001). No notable differences in MCS distance were found when comparing laterality (P > 0.05). Height had a notable effect on all MCS values (P < 0.05). Inter- and intra-rater reliabilities for ultrasonographic MCS measurements were all excellent (interclass correlation coefficient >0.75). Ultrasound can reliably measure the MCS of the ankle while doing dynamic stress manoeuvres. With the deltoid ligament intact, a GST increases MCS widening more than weight-bearing, and holding the ankle in plantarflexion while doing a gravity stress view, further increases this difference. Diagnostic studies-investigating a diagnostic test: Level III.

Full Flight Envelope and Trim Map of Flapping-Wing Micro Aerial Vehicles

Controlling agile and complex air-vehicle maneuvers requires knowledge of the full flight envelope and dominant modes of motion. This paper presents a comprehensive approach for determining the full flight envelope and trim map of minimally actuated flapping-wing micro aerial vehicles that are capable of a broad range of coupled longitudinal–lateral–directional aerobatic maneuvers. By this approach, a representative set of realizable set points and trim conditions can be determined from the flight dynamic model, including asymmetric and unstable maneuvers. Data-driven dynamic mode decomposition is used to identify and analyze the dominant modes of motion both in simulations and physical experiments involving the RoboBee. The dominant eigenplanes and stability characteristics of this flapping-wing robot are successfully validated experimentally for both stable and unstable asymmetric full-envelope maneuvers, including rapidly uncontrolled tumbling.

Dynamic Decoupling and Trajectory Tracking for Automated Vehicles Based on the Inverse System

A simultaneous trajectory tracking and stability control method is present for the four-wheel independent drive (4WID) automated vehicles to handle dynamic coupling maneuvers. To conquer the disadvantage that attendant disturbances caused by the dynamic coupling of traditional decentralized control methods degenerate the trajectory tracking accuracy, the proposed method takes advantage of the idea of decoupling to optimize the tracking performance. After establishing the dynamic model of the 4WID automated vehicles, the coupling mechanism of the vehicle dynamic control and its negative effect on trajectory tracking were studied at first. The inverse system model was then determined by machine learning and connected in series with the controlled object to form a pseudo linear system to realize dynamic decoupling. Finally, differing from previous tracking methods following the apparent lateral position and longitudinal velocity references, the pseudo linear system tracks the ideal intermediate targets transferred from the target trajectory, that is, the accelerations of vehicle in longitudinal, lateral and yaw directions, to indirectly achieve trajectory tracking and validly restrain the vehicle motion. The effectiveness of the proposed method, i.e., the high tracking accuracy and the stable driving performance, is verified through three coupling driving scenarios in the CarSim-Simulink co-simulations platform.

Diagnosing the Impact of the Syndesmotic Injury on Lateral Ankle Stability using Dynamic Ultrasound

Category:Ankle; Basic Sciences/Biologics; Sports; TraumaIntroduction/Purpose:There is a high prevalence of coexisting lateral ankle ligament injuries and syndesmotic ligamentous injuries. However, it is unclear whether syndesmotic ligaments directly contribute toward the stability of the lateral ankle.Dynamic ultrasonography (US) is an imaging modality increasingly used for the care of orthopaedic foot and ankle patients because it allows dynamic evaluation of structures at the point of care with little risk to the patient and at low-cost. The aim of this study is to assess the effect of syndesmotic injury as well as combined syndesmotic and lateral ankle injury on the stability of the lateral ankle.Methods:Sixteen fresh frozen above-knee amputated cadaveric specimens, divided into two groups, underwent ultrasound evaluation for lateral ankle stability. In both the groups, the assessment was first done with all ligaments intact and later with sequential transection of anterior inferior tibiofibular ligament (AITFL), interosseous ligament (IOL), posterior inferior tibiofibular ligament (PITFL), anterior talofibular ligament (ATFL), calcaneofibular ligament (CFL) and posterior talofibular ligament (PTFL). In all scenarios, two loading conditions were considered: (1) Anterior drawer test: 50N and 80N and (2) Lateral clear space (LCS): 1.7Nm torque. The talar translation and LCS to the fixed tibial plafond were measured using Image J. Wilcoxon rank-sum test was used to compare the findings of each ligamentous transection state to the intact state. A p-value <0.05 was considered statistically significant.Results:In group 1 after transection of the all syndesmotic ligament and ATFL, an increase in the anterior drawer and lateral clear space values were found as compared to the intact state. Similarly, in group 2 the anterior drawer and lateral clear space values significantly increased after transection of the AITFL and ATFL as compared to the intact state (p-values = 0.01).Conclusion:Ultrasound can be used to evaluate the impact of the syndesmotic injury on lateral ankle stability while performing dynamic stress maneuvers. Lateral ankle instability appears after injury to all syndesmotic ligaments and ATFL, or after one syndesmotic ligament rupture (AITFL) with a concomitant anterior talofibular ligament rupture (ATFL). These findings suggest that surgeons should lower their threshold for stabilizing the syndesmosis if there is a concomitant lateral ankle ligament injury.

Determination of the dynamic critical maneuvering area in an encounter between two vessels: Operation with negligible environmental disruption

This paper introduces the concept of Collision Avoidance Dynamic Critical Area (CADCA) for onboard Decision Support Systems (DSS). The indicator proposed is derived via identification of a minimum required maneuvering zone in an encounter between two vessels. The CADCA model accounts for ship maneuvering dynamics and associated hydrodynamic actions emerging from different rudder angles and forward speed effects. The method presented is novel as it considers the variability of a critical area due to dynamic changes in operational parameters for both vessels. Results of the simulations carried out in negligible weather conditions confirm that computed zones may differ significantly in terms of shapes and limits. It is demonstrated that the size of the CADCA depends on the rudder angle, forward speed, as well as the dimensions of the vessels.

Frame loads accuracy assessment of semianalytical multibody dynamic simulation methods of a recreational vehicle

The design of a vehicle frame is largely dependent on the loads applied on the suspension and heavy parts mounting points. These loads can either be estimated through full analytical multibody dynamic simulations, or from semi-analytical simulations in which tire and road sub-models are not included and external vehicle loads, recorded during field testing, are used as inputs to the wheel hubs. Several semi-analytical methods exist, with various modeling architectures, yet, it is unclear how one method over another improves frame loads prediction accuracy.This study shows that a semi-analytical method that constrains the vehicle frame center of gravity movement along a recorded trajectory, using a control algorithm, leads to an accuracy within 1% for predicting frame loads, when compared to reference loads from a full analytical model. The control algorithm computes six degrees of freedom forces and moments applied at the vehicle center of gravity to closely follow the recorded vehicle trajectory. It is also shown that modeling the flexibility of the suspension arms and controlling wheel hub angular velocity both contribute in improving frame loads accuracy, while an acquisition frequency of 200 Hz appears to be sufficient to capture load dynamics for several maneuvers. Knowledge of these loads helps engineers perform appropriate dimensioning of vehicle structural components therefore ensuring their reliability under various driving conditions.

Spinal Helical Actuation Patterns for Locomotion in Soft Robots.

Spinal-driven locomotion was first hypothesized to exist in biological systems in the 1980s. However, only recently has the concept been applied to legged robots. In implementing spinal-driven locomotion in robots to-date, researchers have focused on bending in the spine. In this article, we propose an additional mode of spinal-driven locomotion: axial torsion via helical actuation patterns. To study torsional spinal-driven locomotion, a six-legged robot with unactuated legs is used. This robot is designed to be modular to allow for changes in the physical system, such as material stiffness of the spine and legs, and has actuators that spiral around the central elastomeric spine of the robot. A model is provided to explain torsional spinal-driven locomotion. Three spinal gaits are developed to allow the robot to walk forward, through which we demonstrate that the speed of the robot can be influenced by the stiffness of the spine and legs. We also demonstrate that a single gait can be used to drive the robot forward and turn the robot left and right by adjusting the leg positions or foot friction. The results indicate that the inclusion of helical actuation patterns can assist in movement. The addition of these actuation patterns or active axial torsion to future, more complex robots with active leg control may enhance the energy efficiency of locomotion or enable fast, dynamic maneuvering.

3D Kinematic Analysis of the Ollie Maneuver on the Skateboard

This study aims to analyze the tridimensional kinematics of the ollie maneuver on the skateboard and to compare static and dynamic maneuver performance, i.e., without and with a previous row, respectively. Six male participants were analyzed. Thirty-four reflective markers were placed on the skateboarder’s body and four reflective markers on the board. The tridimensional analysis was captured by eleven cameras (100 Hz) (Vicon® system). The analysis of the ollie skateboard maneuver was performed in two different ways: a) without (static maneuver) and b) with (dynamic maneuver) a previous row. The joint angles (ankle, knee and hip), during maximal height center of mass of participants and the skateboard, were compared using the Student’s T-test. The correlation between the center of mass of the participant and the skateboard was calculated using the Pearson Correlation. No significant differences were observed in the maximum height of the joint angles and centers of mass of the participants and the skateboard. The maximal height of the participant’s and the skateboard’s center of mass did not present a significant correlation. The results showed that there is no difference between performing the ollie skateboard maneuver with (static) or without (dynamic) a previous row. However, training to increase the height and improve the performance of the maneuver in general is essential for the skateboarder to achieve a higher score and a greater likelihood of success in sports competitions.

Numerical analysis of escort tug manoeuvrability characteristics – Part II: The skeg effect

This paper presents a CFD-RANS investigation of the effect of the skeg hydrodynamics on the manoeuvrability of an Azimuth Stern Drive Escort Tug. This study is devoted to identifying a proper mathematical model to be included in a dynamic manoeuvring simulator. The hydrodynamic problem is therefore decomposed in the hull and skeg components. The hydrodynamic characteristics of the skeg were so explored by varying its span and chord systematically, allowing deep insight into the physics of both components and their mutual interaction. The distribution of the forces acting on hull and skeg were studied in detail in their dependence from the skeg geometrical characteristics. Suitable mathematical formulations for the skeg forces were implemented in an MMG-like manoeuvring model-based onto the CFD captive simulations. Lastly, the impact on the tug’s manoeuvrability of the previously mentioned variations was then investigated. Turning, Zig-Zag, Escort Capability, Escort Mirror ability and Escort Stability manoeuvres were simulated. The results of these manoeuvres are presented, showing the great potential of this manoeuvring model in representing a wider class of Escort tugs.

Assessment of intraoperative joint loads and mobility in reverse total shoulder arthroplasty through a humeral trial sensor

HypothesisThe use of intraoperative glenohumeral load sensors has the potential to facilitate an objective, quantitative assessment of the soft tissue tension during reverse total shoulder arthroplasty. Material and MethodsA reverse total shoulder arthroplasty was performed on eight fresh frozen cadaveric shoulders, creating three different tightness conditions for each shoulder by using various shim thicknesses attached to an instrumented, load-sensing humeral trial component. The glenohumeral loads were recorded during four dynamic maneuvers, consisting of maximum internal/external rotation at 0°, 45° and 90° abduction and forward elevation. The joint kinematics were synchronously recorded using an optical tracking system. ResultsFor normal tightness conditions, 98.3% of the observed loads were below 40 lbf. These loads varied through the range of motion with an increase in glenohumeral loads generally observed towards the limits of the range of motion. With increasing shoulder tightness, the range of motion of the joint was not significantly affected, though the average and maximum glenohumeral load significantly increased (p < 0.01 for all). ConclusionIn a cadaveric setting, higher glenohumeral loads were observed at higher tightness conditions, demonstrating the potential of a load-sensing humeral trial component to quantify intraoperative joint load with reverse total shoulder arthroplasty. The glenohumeral loads are increasing towards the limits of the range of motion, indicating the importance of performing dynamic assessment of stability at the extents of the range of motion during implant trialing. Level of EvidenceBasic Science Study

Multi-UUV Cooperative Dynamic Maneuver Decision-Making Algorithm Using Intuitionistic Fuzzy Game Theory

In this paper, a multi-unmanned underwater vehicle (UUV) cooperative dynamic maneuver decision-making algorithm is proposed based on the combination of game theory and intuitionistic fuzzy sets. Underwater environments with weak connectivity, underwater noise, and dynamic uncertainties are fully considered through intuitionistic fuzzy sets, which solves one of the main problems in making decisions underwater. Subsequently, the intuitionistic fuzzy multiattribute evaluation of a UUV maneuver strategy is conducted, and the intuitionistic fuzzy payment matrix of the cooperative dynamic maneuver game is obtained. Thereafter, the Nash equilibrium condition is proposed to satisfy the intuitionistic fuzzy total order, and the Nash equilibrium maneuver decision-making model under a dynamic underwater environment is established. Meanwhile, the modified particle swarm optimization method is presented to solve the established problem and find the optimal strategy. Finally, an example is used to verify the superiority of the proposed cooperative dynamic maneuver decision-making algorithm.