Motion Simulation Software Research Articles

FPID-RCP: A Control Method for a Swing-Type Wave Compensation Platform System

With the rapid development of marine engineering in recent years, offshore operations have become increasingly common, making wave compensation platforms crucial for safe operations at sea. This paper presents a pendulum-type wave compensation platform specifically designed for wave compensation applications. The main components of this wave compensation platform include a chassis, support base, hydraulic cylinders, telescopic rods, upper platform, three sets of balancing mechanisms, three sets of tilt angle sensors, and a control system. Firstly, to thoroughly understand the compensatory motion of the pendulum-type three-degree-of-freedom wave compensation platform, kinematic analysis of the entire system was conducted, and the motion inverse solution curves of the mechanism were obtained through simulation using motion simulation software. Secondly, to enhance the compensatory response performance of the platform, a fuzzy PID control algorithm was employed to control the system and achieve attitude control of the platform. Finally, through control system simulation, compared to PID control, fuzzy PID reduces system response delay and successfully meets the expected technical requirements and application needs.

Calibration of micro-simulation model in assessment of passenger car exhaust emission during acceleration

In terms of simulation research, it is important to simulate real conditions as precisely as possible. This type of approach makes it possible to minimize the error in the obtained results. The dynamics of acceleration is one of the most important factors having a direct impact on fuel consumption and exhaust emissions from vehicles. The work was carried out with the use of PTV Vissim microscopic vehicle motion simulation software. The considerations were carried out on theoretical acceleration profiles with different dynamics values and the actual character of acceleration, recorded during road tests. The simulations were carried out for a car powered by spark-ignition and compression-ignition engines. The research showed that the calibration of the acceleration character of the vehicle in simulation tests may result in significant differences in obtained results of exhaust emissions.

Effect of motion simulation programs in teaching force concept1

The most important concept in dynamics is force. Teaching forces in secondary schools has many difficulties, due to the fact that when students start learning dynamics, they have already developed a force concept based on their everyday experiences. This concept is usually simplified and often confused with impulse. However, the concept taught on physics lessons, is a much more complex, based on a vectorial quantity, with a time-dependent direction and magnitude. This confusion of concepts can be largely eliminated by the visualization of force vectors during the motion of an object. This opportunity is available in motion-simulation software, which work as a digital sandbox, allowing users to create their own scenes and display force vectors during the simulations. Connecting kinematics by motion visualization and dynamics by force visualization is a powerful tool that helps students to develop deeper understanding in mechanics. In our educational research, we investigated the positive effect of using such a program. With the participation of 700 students, divided into experimental and reference groups, we measured their development in understanding mechanics. The results proved that students who used the simulation program reach a better functional understanding of the concept of force than those being in the reference group.

OBTAINING THE PARAMETRIC POSITION EQUATIONS OF A FOUR-BAR MECHANISM USING THE PARAMETRIC POSITION EQUATIONS OF THE PLANAR MANIPULATOR WITH 3 REVOLUTE JOINTS (3RM)

In a four-bar mechanism, the crank link rotates at a constant angular velocity, while the other two links have constantly changing angular velocities. If it is desired to convert a 3RM into a four-bar mechanism, the variable angular velocities of the rotary actuators at both ends of the coupler link should be accurate. The general parametric set of equations that give the cartesian coordinates of 3RM can be arranged so that they can be used for the four-bar mechanism by limiting the degree of freedom. In this case, the angular velocities of the actuators on both ends of the coupler link should be determined while the crank link rotates at a constant angular speed. Angular velocities of actuators have been obtained using the WorkingModel2D (WM2D) "dynamic motion-simulation software" for a four-bar mechanism, whose geometric parameters have been selected as the crank-rocker. Using the angular velocity data, unknown coefficients in polynomials expressing the angular velocities of the rotary actuators connected to the coupler link have been found using Mathematica software. The trajectory and angular velocity data have been obtained from WM2D, the results of trajectory and angular velocity equations have been compared and the results have been at acceptable levels.

Simulation Analysis and Experimental Research on Silage Corn Crushing and Throwing Device

HIGHLIGHTS The mechanism of straw smashing was analyzed. Factors such as the speed of the cutter shaft, the number of blades, the thickness, and the inclination angle had a greater impact on the theoretical length of the straw section after crushing. Based on the straw crushing mechanism, the structure of the crushing chamber was designed. The corn stalk crushing and sending device was trial-produced and field experiments were carried out. ABSTRACT . In order to further improve the crushing quality of corn stalks, this research designs a corn stalk crushing and throwing device. First, it introduced the overall structure and working principle, and analyzed the crushing mechanism of corn stalks to obtain the main factors affecting its crushing performance. Then, the crushing blade in the crushing chamber was designed to determine that the number of crushing blades was 10. Kinematics and dynamic balance analysis, and the establishment of a mathematical model, the speed range of the crushing cutter shaft was 530~900 r/min. On this basis, the ADAMS motion simulation software was used to measure the change curves of the restraint force, runout, and acceleration of the shaft end with different speeds of the crushing cutter shaft. The simulation analysis finally determined that when the speed of the crushing knife shaft was 700 r/min, and the working performance of the device was better and meets the requirements of dynamic balance. Finally, the verification test was carried out, and the result shows: when the speed of the crushing knife shaft was 700 r/min, the qualified rate of corn stalk crushing length was 93.65%. Compared with the original silage corn crushing and throwing device, the performance had increased by 4.78%. It meets the standard of corn stalk crushing operation, which can provide a theoretical basis and scientific basis for the design and optimization of corn stalk crushing and returning equipment. Keywords: Crushing mechanism, Dynamic balance, Motion simulation, Silage corn.

The dynamic characteristic analysis on Cartesian coordinate robot

In this paper, the finite element analysis of the Cartesian coordinate robot and the modal analysis of the whole system of the robot are carried out. The axes of the robot will not resonate with the whole structure of the robot in the moving state. The motion of the first three workpieces is analyzed by using ADAMS motion simulation software. It is concluded that the robot motion state is stable, the speed changes smoothly, and the trajectory runs reasonably.

Dynamic analysis of the harvester seat

The comfort of the harvester seat is the key to the overall comfort experience, the comfort of the seat mainly includes static comfort and dynamic comfort. The seat human body model is established by the CAD software CATIA, and the joint angles of the human body in a suitable sitting posture are obtained. The simulation results of the motion simulation software ADAMS are analyzed. The results show that the acceleration of the seat increases with the increase of the seat suspension stiffness. As the seat suspension damping increases, the seat acceleration decreases. The appropriate range of seat suspension stiffness is 80 – 120N/mm, the appropriate range of damping is 3 – 5N ⋅ s/mm.

Research on Key Process Technology for Profile Electrolytic Finishing of Large Marine Propeller Impeller

Abstract An electrolysis process method for free-form blade surface finishing is proposed for a free-form surface impeller, and a stepwise method is used to process the inter-blade channel of the overall impeller. The forming cathode is then used to finish the blade to meet the blade processing requirements. In the design, the forming cathode structure was improved by using motion simulation software, and the flow field simulation software was used to simulate and analyze the cathode flow channel. The cathode shape and the electrolyte flow rate between the electrodes meet the processing requirements. In the process of processing experiments, the motion path of the cathode was analyzed and optimized. The effect of the feed direction on the uneven distribution of the blade machining gap was reduced through optimization, and high-frequency pulse power processing was used to reduce the machining gap and improve the machining accuracy of the blade. The experimental results show that the process scheme is feasible and the precision of the processed impeller free-form surface is significantly improved. The material is a monolithic turbine disk of high-temperature alloys, and its large twisted blade processing has always been a problem in the manufacturing industry.

TU‐D‐202‐02: Make Margins Simple: Use Real‐Time Target Tracking

Respiratory motion has long been recognized as an important factor affecting the precision of radiotherapy. After the introduction of the 4D CT to visualize the respiratory motion in 3D, the internal target volume (ITV) has been widely adopted as simple method to take the motion into account in treatment planning and delivery. The ITV is generated as the union of the CTVs as the patient goes through the respiratory cycle. Many issues have been identified with the ITV. In this session three alternatives for the ITV will be discussed: 1) An alternative motion‐inclusive approach with better imaging and smaller margins, called mid‐position CT. 2) The tracking approach and 3) The gating approach.The following topics will be addressed by Marcel van Herk (“Is ITV the correct motion encompassing strategy”): Magnitude of respiratory motion, effect of motion on radiotherapy, motion encompassing strategies, and software solutions to assist in motion encompassing strategies. Then Paul Keall (“Make margins simple: Use real‐time target tracking”) will discuss tracking with: clinical drivers for tracking, current clinical status of tumor tracking, future tumor tracking technology, and margin margin challenges with and without tracking. Finally Daniel Low will discuss gating (“Gating is the best ITV killer”): why ITV in the first place, requirements for planning, requirements at the machine, benefits and costs.The session will end with a discussion and live demo of motion simulation software to illustrate the issues and explain the relative benefit and appropriate uses for the three methods. Learning Objectives: Explain the 4D imaging and treatment planning process. Summarize the various approaches to deal with respiratory motion during radiotherapy Discuss the tradeoffs involved when choosing one of the three discussed approaches. Explain in which situation each method is the best choiceResearch is partly funded by Elekta Oncology Systems and the Dutch Cancer Foundation; M. van Herk, Part of the research was funded by Elekta Oncology Systems and the Dutch Cancer Foundation

TU‐D‐202‐03: Gating Is the Best ITV Killer

Respiratory motion has long been recognized as an important factor affecting the precision of radiotherapy. After the introduction of the 4D CT to visualize the respiratory motion in 3D, the internal target volume (ITV) has been widely adopted as simple method to take the motion into account in treatment planning and delivery. The ITV is generated as the union of the CTVs as the patient goes through the respiratory cycle. Many issues have been identified with the ITV. In this session three alternatives for the ITV will be discussed: 1) An alternative motion‐inclusive approach with better imaging and smaller margins, called mid‐position CT. 2) The tracking approach and 3) The gating approach.The following topics will be addressed by Marcel van Herk (“Is ITV the correct motion encompassing strategy”): Magnitude of respiratory motion, effect of motion on radiotherapy, motion encompassing strategies, and software solutions to assist in motion encompassing strategies. Then Paul Keall (“Make margins simple: Use real‐time target tracking”) will discuss tracking with: clinical drivers for tracking, current clinical status of tumor tracking, future tumor tracking technology, and margin margin challenges with and without tracking. Finally Daniel Low will discuss gating (“Gating is the best ITV killer”): why ITV in the first place, requirements for planning, requirements at the machine, benefits and costs.The session will end with a discussion and live demo of motion simulation software to illustrate the issues and explain the relative benefit and appropriate uses for the three methods. Learning Objectives: Explain the 4D imaging and treatment planning process. Summarize the various approaches to deal with respiratory motion during radiotherapy Discuss the tradeoffs involved when choosing one of the three discussed approaches. Explain in which situation each method is the best choiceResearch is partly funded by Elekta Oncology Systems and the Dutch Cancer Foundation; M. van Herk, Part of the research was funded by Elekta Oncology Systems and the Dutch Cancer Foundation

TU‐D‐202‐01: Is ITV the Correct Motion Encompassing Strategy?

Respiratory motion has long been recognized as an important factor affecting the precision of radiotherapy. After the introduction of the 4D CT to visualize the respiratory motion in 3D, the internal target volume (ITV) has been widely adopted as simple method to take the motion into account in treatment planning and delivery. The ITV is generated as the union of the CTVs as the patient goes through the respiratory cycle. Many issues have been identified with the ITV. In this session three alternatives for the ITV will be discussed: 1) An alternative motion‐inclusive approach with better imaging and smaller margins, called mid‐position CT. 2) The tracking approach and 3) The gating approach.The following topics will be addressed by Marcel van Herk (“Is ITV the correct motion encompassing strategy”): Magnitude of respiratory motion, effect of motion on radiotherapy, motion encompassing strategies, and software solutions to assist in motion encompassing strategies. Then Paul Keall (“Make margins simple: Use real‐time target tracking”) will discuss tracking with: clinical drivers for tracking, current clinical status of tumor tracking, future tumor tracking technology, and margin margin challenges with and without tracking. Finally Daniel Low will discuss gating (“Gating is the best ITV killer”): why ITV in the first place, requirements for planning, requirements at the machine, benefits and costs.The session will end with a discussion and live demo of motion simulation software to illustrate the issues and explain the relative benefit and appropriate uses for the three methods. Learning Objectives: Explain the 4D imaging and treatment planning process. Summarize the various approaches to deal with respiratory motion during radiotherapy Discuss the tradeoffs involved when choosing one of the three discussed approaches. Explain in which situation each method is the best choiceResearch is partly funded by Elekta Oncology Systems and the Dutch Cancer Foundation; M. van Herk, Part of the research was funded by Elekta Oncology Systems and the Dutch Cancer Foundation

TU‐D‐202‐00: Rest In Peace ‐ ITV

Respiratory motion has long been recognized as an important factor affecting the precision of radiotherapy. After the introduction of the 4D CT to visualize the respiratory motion in 3D, the internal target volume (ITV) has been widely adopted as simple method to take the motion into account in treatment planning and delivery. The ITV is generated as the union of the CTVs as the patient goes through the respiratory cycle. Many issues have been identified with the ITV. In this session three alternatives for the ITV will be discussed: 1) An alternative motion‐inclusive approach with better imaging and smaller margins, called mid‐position CT. 2) The tracking approach and 3) The gating approach.The following topics will be addressed by Marcel van Herk (“Is ITV the correct motion encompassing strategy”): Magnitude of respiratory motion, effect of motion on radiotherapy, motion encompassing strategies, and software solutions to assist in motion encompassing strategies. Then Paul Keall (“Make margins simple: Use real‐time target tracking”) will discuss tracking with: clinical drivers for tracking, current clinical status of tumor tracking, future tumor tracking technology, and margin margin challenges with and without tracking. Finally Daniel Low will discuss gating (“Gating is the best ITV killer”): why ITV in the first place, requirements for planning, requirements at the machine, benefits and costs.The session will end with a discussion and live demo of motion simulation software to illustrate the issues and explain the relative benefit and appropriate uses for the three methods. Learning Objectives: Explain the 4D imaging and treatment planning process. Summarize the various approaches to deal with respiratory motion during radiotherapy Discuss the tradeoffs involved when choosing one of the three discussed approaches. Explain in which situation each method is the best choiceResearch is partly funded by Elekta Oncology Systems and the Dutch Cancer Foundation; M. van Herk, Part of the research was funded by Elekta Oncology Systems and the Dutch Cancer Foundation

Approximation of the functional kinematics of posterior stabilised total knee replacements using a two-dimensional sagittal plane patello-femoral model: comparing model approximation to in vivo measurement

Previous in vivo studies have observed that current designs of posterior stabilised (PS) total knee replacements (TKRs) may be ineffective in restoring normal kinematics in Late flexion. Computer-based models can prove a useful tool in improving PS knee replacement designs. This study investigates the accuracy of a two-dimensional (2D) sagittal plane model capable of predicting the functional sagittal plane kinematics of PS TKR implanted knees against direct in vivo measurement. Implant constraints are often used as determinants of anterior–posterior tibio-femoral positioning. This allowed the use of a patello-femoral modelling approach to determine the effect of implant constraints. The model was executed using motion simulation software which uses the constraint force algorithm to achieve a solution. A group of 10 patients implanted with Scorpio PS implants were recruited and underwent fluoroscopic imaging of their knees. The fluoroscopic images were used to determine relative implant orientation using a three-dimensional reconstruction method. The determined relative tibio-femoral orientations were then input to the model. The model calculated the patella tendon angles (PTAs) which were then compared with those measured from the in vivo fluoroscopic images. There were no significant differences between the measured and calculated PTAs. The average root mean square error between measured and modelled ranged from 1.17° to 2.10° over the flexion range. A sagittal plane patello-femoral model could conceivably be used to predict the functional 2D kinematics of an implanted knee joint. This may prove particularly useful in optimising PS designs.

Identification and Optimization of Diagonal Shift Failure in Manual Transmission Using Simulation Software

In the past the focus in the transmission development used to be mainly on durability of the components. Despite that shift quality has improved significantly in the last years. Increasing customer expectation has made it necessary to further change the focus in transmission development toward better shifting system. Manual transmission shifting system is having lots of performance-related problems, due to its complex design structure. Smooth shift and select operations will be disturbed if there is small malfunction in the system. Motion simulation software can be an excellent tool to identify and resolve most of the shifting system failure related to its mechanism. Designers can rectify the problems of the shifting system by simulating the mechanism using motion simulation software. This article presents an interesting opportunity of motion simulation software to identify and optimize the shifting system mechanism failures in the manual transmission.

The biomechanical modelling of non-ballistic skin wounding: blunt-force injury

Knowledge of the biomechanical dynamics of blunt force trauma is indispensable for forensic reconstruction of a wounding event. In this study, we describe and interpret wound features on a synthetic skin model under defined laboratory conditions. To simulate skin and the sub-dermal tissues we used open-celled polyurethane sponge (foam), covered by a silicone layer. A drop tube device with three tube lengths (300, 400, and 500 mm), each secured to a weighted steel scaffold and into which a round, 5-kg Federal dumbbell of length 180 mm and diameter 8 cm was placed delivered blows of known impact. To calculate energy and velocity at impact the experimental set-up was replicated using rigid-body dynamics and motion simulation software. We soaked each foam square in 500 mL water, until fully saturated, immediately before placing it beneath the drop tube. We then recorded and classified both external and internal lacerations. The association between external wounding rates and the explanatory variables sponge type, sponge thickness, and height were investigated using Poisson regression. Tears (lacerations) of the silicone skin layer resembled linear lacerations seen in the clinical literature and resulted from only 48.6% of impacts. Poisson regression showed there was no significant difference between the rate of external wounding for different sponge types (P = 0.294) or different drop heights (P = 0.276). Most impacts produced "internal wounds" or subsurface cavitation (96%). There were four internal "wound" types; Y-shape (53%), linear (25%), stellate (16%), and double crescent (6%). The two-way interaction height by sponge type was statistically significant in the analysis of variance model (P = 0.035). The other two-way interactions; height by thickness and sponge type by thickness, were also bordering on statistical significance (P = 0.061 and P = 0.071, respectively). The observation that external wounds were present for less than half of impacts only, but that nearly all impacts resulted in internal wounds, might explain the observed haematoma formation and contusions so often associated with blunt-force injuries. Our study also confirms the key role of hydrodynamic pressure changes in the actual tearing of subcutaneous tissue. At the moment and site of impact, transferred kinetic energy creates a region of high pressure on the fluid inside the tissue. As a result of the incompressibility of the fluid, this will be displaced away from the impact at a rate that depends on the velocity (or kinetic energy) of impact and the permeability and stiffness of the polymeric foam and skin layer.

A Validated Two-Dimensional Model to Predict TKR Functional Kinematics

INTRODUCTION Posterior Stabilized (PS) Total Knee Replacement (TKR) design utilises a cam and post mechanism to generate femoral rollback in higher flexion. The construct is designed to replicate the function of the posterior cruciate ligament (PCL). There is much interest in obtaining optimum post cam engagement to achieve normal femoral rollback and improved outcome after TKR. Previous studies [1] have observed that the PS knee may be ineffective in restoring normal kinematics in high flexion. However, such patient based fluoroscopic studies are demanding in terms of resources and time. Ideally, computer based modelling methodologies can offer a more suitable adjunct. The aims of this study were to develop a validated model capable of predicting the functional kinematics of PS TKR implanted knees, and compare results obtained using this model to those measured in vivo as validation. METHODS Functional kinematics were assessed using the Patella Tendon Angle (PTA) (the angle subtended between the patella tendon and the long axis of the tibia). PTA provides a valid assessment of relative tibial-femoral position [1] and as such is taken as the output of the model. The input to the model is the relative tibial femoral position. This allows the use of a patella-femoral modelling approach similar to that developed by Gill & O’Connor [2]. The model was executed using motion simulation software which uses the constraint force algorithm [3] to achieve a solution, the output parameter being the PTA. A group of ten patients implanted with Scorpio PS implants, at least one year previously for an underlying diagnosis of osteoarthritis, were recruited. The patients were asked to perform a step-up exercise and a deep knee bend whilst undergoing fluoroscopic imaging. The fluoroscopic images were subsequently corrected for distortion and the relative implant orientation was achieved using a 3D reconstruction method. The determined relative tibial femoral orientations were then input to the model. The mathematically obtained PTAs were then compared to those measured from in vivo fluoroscopy images using an established protocol [1]. The mean PTA values for each each data set were compared using paired t tests at 10 degree flexion intervals. Variation between model and in vivo data was further explored using root mean square analysis RESULTS The mean PTA measured in vivo ranged from 11 in extension to -1 at 100 flexion (fig.1). The mean PTA obtained using the model for the same patients was similar ranging from 10 in extension to 0 at 100 flexion. There was no significant difference between the PTAs for the data sets at any point in the range. A large standard deviation is present for both mathematically derived and in vivo data sets. The average root mean square error (RMSE) ranged between 1.17 and 2.10 over the flexion range. Table 1 shows the average RMSE and its standard deviation as well as the significance at 10 intervals.

Motion Simulation With Working Model 2D and MSC.visualNastran 4D

Motion Simulation With Working Model 2D and MSC.visualNastran 4D

Stature, Age, and Gender Effects on Reach Motion Postures

The rapid adoption of software to simulate human reach motions in the design of vehicle interiors and manufacturing and office workstations has required a sophisticated understanding of human motions. This paper describes how more than 3,000 right-arm reaching motions of a diverse group of participants were captured and statistically modeled. The results demonstrate that stature and age have a larger effect than does gender on reach motion postures for motions chosen by the participants while reaching to targets placed throughout a typical automobile interior. We propose that these methods, models, and results can assist the further development of human motion simulation software for ergonomic purposes, such as for the design or evaluation of vehicle interiors or industrial workplaces, to ensure that various population groups are physically accommodated.