Robot Simulation System Research Articles

Biomechanical simulation of segmented intrusion of a mandibular canine using Robot Orthodontic Measurement & Simulation System (ROSS)

ObjectiveAim of this study was to investigate the forces and moments during segmented intrusion of a mandibular canine using Cantilever-Intrusion-Springs (CIS). MethodsThree different CIS modifications were investigated using a robotic biomechanical simulation system: unmodified CIS (#1, control), CIS with a lingual directed 6° toe-in bend (#2), and CIS with an additional 20° twist bend (#3). Tooth movement was simulated by the apparative robotic stand, controlled by a force-control algorithm, recording the acting forces and moments with a force-torque sensor. Statistical analysis was performed using Shapiro-Wilk, Kolmogorov-Smirnov, Kruskal-Wallis ANOVA and post hoc tests with Bonferroni correction (α = 0.05). ResultsThe initial intrusive force, which was uniformly generated by a 35° Tip-Back bend, decreased significantly (p < 0.05) from 0.31 N in group (#1) to 0.28 N in group (#3). Vestibular crown tipping reduced significantly (p < 0.05) from 2.11° in group (#1) and 1.72° in group (#2) to 0.05° in group (#3). Matching to that the direction of orovestibular force significantly (p < 0.05) shifted from 0.15 N to vestibular in group (#1) to 0.51 N to oral in group (#3) and the orovestibular tipping moment decreased also significantly (p < 0.05) from 4.63 Nmm to vestibular in group (#1) to 3.56 Nmm in group (#2) and reversed to 1.20 Nmm to oral in group (#3). Apart from that the orovestibular displacement changed significantly (p < 0.05) from 0.66 mm in buccal direction in group (#1) to 0.29 mm orally in group (#2) and 1.49 mm in oral direction as well in group (#3). SignificanceNone of the modifications studied achieved pure mandibular canine intrusion without collateral effects. The significant lingual displacement caused by modification (#3) is, not least from an aesthetic perspective, considered much more severe than a slight tipping of the canine. Consequently, modification (#2) can be recommended for clinical application based on the biomechanical findings.

An Approach for Identifying Dynamic Parameters in Robotic Systems with Inconsistent Joint Measurements

Abstract Achieving accurate robot control and realistic robot simulation relies on the precise modeling of robotic dynamics. Although the identification method for obtaining dynamic parameters has been developed for several years, joint inconsistency has largely been disregarded in prior studies. The inconsistency of joint actuators results in varying confidence levels of their measurement results, leading to the departure of the final identification parameters from valid values, thereby impacting the control performance. This paper presents a novel identification method that effectively addresses the issue of joint inconsistency by assigning distinct weights to each joint. The presented approach extends the least square (LS) method and incorporates the particle swarm optimization (PSO) algorithm to calculate the weights of each individual joint. This approach is referred to as PWLS (PSO-based weighted least square). Simulation experiments demonstrated the superior identification accuracy of the PWLS method compared to the LS method in a robot system characterized by joint inconsistency. Moreover, the experiments were performed on a 3-degree-of-freedom (DoFs) robotic limb, which exhibited improved identification performance in both the excitation and verification trajectories. These findings have promising implications for enhancing the control and simulation of robotic systems.

SIMULACIÓN AVANZADA DE UN BRAZO ROBÓTICO CON 2 GRADOS DE LIBERTAD, CONTROLADO EN SIMSCAPE

In this project, a robotic arm was developed, modeled, and implemented using the Matlab Simulink programming platform. The robotic arm was designed with 2 degrees of freedom and equipped with three motors, allowing for precise and coordinated control of its movements. For simulating the dynamic and kinematic behavior of the arm, Simscape blocks were used, facilitating a detailed three-dimensional representation of the system. The main objective of the project was to demonstrate a simulation of the robotic arm that allows for precise control of the movement angles. Through a detailed 3D simulation in Simscape, the movement and interaction of the arm's components could be visualized, validating its capability to perform tasks with high precision and efficiency. The results obtained demonstrate the effectiveness of using Simulink and Simscape in the design and simulation of robotic systems, highlighting the importance of these tools for automated development.

The multidirectional roles of the anterior oblique ligament and dorsoradial ligament of the thumb carpometacarpal joint.

The multidirectional biomechanics of the thumb carpometacarpal (CMC) joint underlie the remarkable power and precision of the thumb. Because of the unconfined nature of thumb CMC articulation, these biomechanics are largely dictated by ligaments, notably the anterior oblique ligament (AOL) and the dorsoradial ligament (DRL). However, the rotational and translational stabilizing roles of these ligaments remain unclear, as evidenced by the variety of interventions employed to treat altered pathological CMC biomechanics. The purpose of this study was to determine the effects of sectioning the AOL (n = 8) or DRL (n = 8) on thumb CMC joint biomechanics (rotational range-of-motion [ROM] and stiffness, translational ROM) in 26 rotational directions, including internal and external rotation, and in eight translational directions. Using a robotic musculoskeletal simulation system, the first metacarpal of each specimen (n = 16) was rotated and translated with respect to the trapezium to determine biomechanics before and after ligament sectioning. We observed the greatest increase in rotational ROM and decrease in rotational stiffness in flexion directions and internal rotation following DRL transection and in extension directions following AOL transection. The greatest increase in translational ROM was in dorsal and radial directions following DRL transection and in volar directions following AOL transection. These data suggest the AOL and DRL play complementary stabilizing roles, primarily restraining translations in the direction of and rotations away from the ligament insertion sites. These findings may inform future interventions or implant designs for pathological CMC joints.

The passive biomechanics of the thumb carpometacarpal joint: An in vitro study

The thumb carpometacarpal (CMC) joint facilitates multidirectional motion of the thumb and affords prehensile power and precision. Traditional methods of quantifying thumb CMC kinematics have been largely limited to range-of-motion (ROM) measurements in 4 orthogonal primary directions (flexion, extension, abduction, adduction) due to difficulties in capturing multidirectional thumb motion. However, important functional motions (e.g., opposition) consist of combinations of these primary directions, as well as coupled rotations (internal and external rotation) and translations. Our goal was to present a method of quantifying the multidirectional in vitro biomechanics of the thumb CMC joint in 6 degrees-of-freedom. A robotic musculoskeletal simulation system was used to manipulate CMC joints of 10 healthy specimens according to specimen-specific joint coordinate systems calculated from computed tomography bone models. To determine ROM and stiffness (K), the first metacarpal (MC1) was rotated with respect to the trapezium (TPM) to a terminal torque of 1 Nm in the four primary directions and in 20 combinations of these primary directions. ROM and K were also determined in internal and external rotation. We found multidirectional ROM was greatest and K least in directions oblique to the primary directions. We also found external rotation coupling with adduction-flexion and abduction-extension and internal rotation coupling with abduction-flexion and adduction-extension. Additionally, the translation of the proximal MC1 was predominantly radial during adduction and predominantly ulnar during abduction. The findings of this study aid in understanding thumb CMC joint mechanics and contextualize pathological changes for future treatment improvement.

Application of Computer Virtual Reality Technology in Welding Simulation Training of Complex Structures Based on Unity3D

A virtual reality welding robot simulation system for practical application is developed based on the training and application of welding robot for practical application, which has important theoretical and practical application value for promoting the development of industrial robots in China. The simulation system is synchronized with the welding simulation training platform to achieve the purpose of VR simulation of the welding robot. By modeling the welding process, the process parameters can be inferred automatically, and the digital twin knowledge base for practical application is built. The OPC UA protocol is used to realize real-time communication with mobile devices. The digital twinning technology of CNC machine tool is studied through the simulation experiment of weld motion. This system lays a foundation for realizing the intelligentization of CNC machine tools.

Biomechanical Simulation of Orthodontic En-Bloc Retraction Comparing Compound Technique and Sliding Mechanics Using a HOSEA Robotic Device.

En-bloc retraction is a common procedure in orthodontic therapy. The application of palatal root torque moments is required to control incisor inclination during retraction, yet studies comparing forces and moments with respect to different mechanics are lacking. This study aimed to investigate the forces and moments during orthodontic en-bloc retraction using a robotic biomechanical simulation system, comparing two distinct approaches: (I) compound technique [stainless steel (SS) combined with nickel-titanium (NiTi)] using industrially pretorqued retraction-torque-archwires (RTA) in combination with NiTi closed coil springs; (II) conventional sliding mechanics using SS archwires with manually applied anterior twist bends in combination with elastic chains. Two dimensions (0.017" × 0.025" and 0.018" × 0.025") and ten archwires per group were investigated using 0.022" slot self-ligating brackets. Kruskal-Wallis tests with a significance level of α = 0.05 were conducted. The biomechanical simulation showed that en-bloc retraction was characterized by a series of tipping and uprighting movements, differing significantly regarding the examined mechanics. Collateral forces and moments occurred in all groups. Notably, RTA exhibited fewer extrusive forces. The most bodily movement was achieved with the compound technique and the 0.018" × 0.025" RTA. Sliding mechanics exhibited maximum palatal root torque moments of more than 20 Nmm, exceeding recommended values.

Investigation of Forces and Moments during Orthodontic Tooth Intrusion Using Robot Orthodontic Measurement and Simulation System (ROSS).

The Robot Orthodontic Measurement and Simulation System (ROSS) is a novel biomechanical, dynamic, self-regulating setup for the simulation of tooth movement. The intrusion of the front teeth with forces greater than 0.5 N poses a risk for orthodontic-induced inflammatory root resorption (OIIRR). The aim was to investigate forces and moments during simulated tooth intrusion using ROSS. Five specimens of sixteen unmodified NiTi archwires and seven NiTi archwires with intrusion steps from different manufacturers (Forestadent, Ormco, Dentsply Sirona) with a 0.012″/0.014″/0.016″ wire dimension were tested. Overall, a higher wire dimension correlated with greater intrusive forces Fz (0.012″: 0.561-0.690 N; 0.014″: 0.996-1.321 N; 0.016″: 1.44-2.254 N) and protruding moments Mx (0.012″: -2.65 to -3.922 Nmm; 0.014″: -4.753 to -7.384 Nmm; 0.016″: -5.556 to -11.466 Nmm) during the simulated intrusion of a 1.6 mm-extruded upper incisor. However, the 'intrusion efficiency' parameter was greater for smaller wire dimensions. Modification with intrusion steps led to an overcompensation of the intrusion distance; however, it led to a severe increase in Fz and Mx, e.g., the Sentalloy 0.016″ medium (Dentsply Sirona) exerted 2.891 N and -19.437 Nmm. To reduce the risk for OIIRR, 0.014″ NiTi archwires can be applied for initial aligning (without vertical challenges), and intrusion steps for the vertical levelling of extruded teeth should be bent in the initial archwire, i.e., 0.012″ NiTi.

Biomechanical simulation of forces and moments of initial orthodontic tooth movement in dependence on the used archwire system by ROSS (Robot Orthodontic Measurement & Simulation System)

ObjectivesAim of this study was to determine the forces and moments during simulated initial orthodontic tooth movements using a novel biomechanical test setup. MethodsThe test setup consisted of an industrial precision robot with a force-torque sensor, a maxillary model and a control computer and software. Forces and moments acting on the corresponding experimental tooth during the motion simulations were dynamically measured for two 0.016” NiTi round archwires (Sentalloy Light/Sentalloy Medium). Intrusive (#1), rotational (#2) and angular (#3) tooth movements were simulated by a control program based on the principle of force control and executed by the robot. The results were statistically analysed using K–S-test and Mann-Whitney U test with a significance level of α = 5%. ResultsSentalloy Medium archwires generated higher forces and moments than the Sentalloy Light archwires in all simulations. In simulation #1 the mean initial forces/moments reached 1.442 N/6.781 Nmm for the Light archwires and 1.637 N/9.609 Nmm for the Medium archwires. In movement #2 Light archwires generated mean initial forces/moments of 0.302 N/−8.271 Nmm whereas Medium archwires generated 0.432 N/−9.653 Nmm. Simulation #3 showed mean initial forces/moments of −0.122 N/8.477 Nmm from the Light archwires compared to −0.300 N/11.486 Nmm for the Medium archwires. SignificanceThe measured forces and moments were suitable for initial orthodontic tooth movement in simulations #2 and #3, however inadequate in simulation #1. Reduced archwire dimensions (<0.016″) should be selected for initial leveling of vertical malocclusions.

Simulation Environment of Unmanned Group Reconnaissance System Based on RVIZ and GYM

This paper studies the simulation environment of the current cluster unmanned system, analyzes the shortcomings of the cluster unmanned system, and designs a cluster robot simulation system based on RVIZ and GYM, which has both the fast training algorithm and the physical attributes of the simulation environment, and uses DDS to transmit robot control instructions and state information. After the GYM fast training algorithm, Control the cluster robots to verify the algorithm and collect the state information of the robots in the physical simulation environment of RVIZ. After the whole simulation is passed, the algorithm can be directly used for the path planning of cluster robots. The results show that the simulation environment can effectively simulate the unmanned group reconnaissance system.

Embedding Digital Twin Technology in Robotics

The relevance of introducing digital twin technology in robotics is substantiated, which allows testing and modelling the capabilities of robots, such as manipulation, grasping, etc., using virtual robot prototypes that are identical copies of physical robot prototypes. An overview of the key components of the digital twin framework for robotics, including the physical element, virtual element, middleware, service and transport components, is provided. A technology for designing a robot using digital twins is proposed, including the design of a computer model of a robot using a computer-aided design system or three-dimensional graphics packages, the use of robot simulation systems, data management, data analysis and human-machine interaction. The further development of the research is the implementation of digital twin technology for a rescue robot according to the proposed stages: building a computer model, programming robot behaviour in a simulation system, developing a mathematical and digital model of the robot, implementing human-machine interaction between a physical robot and its digital replica, which will allow testing the interaction of the main components of the digital twin, performing data exchange between the physical and digital replica, and building a digital data model to verify the main operations.

Tacchi: A Pluggable and Low Computational Cost Elastomer Deformation Simulator for Optical Tactile Sensors

Simulation is widely applied in robotics research to save time and resources. There have been several works to simulate optical tactile sensors that leverage either a smoothing method or Finite Element Method (FEM). However, elastomer deformation physics is not considered in the former method, whereas the latter requires a massive amount of computational resources like a computer cluster. In this work, we propose a pluggable and low computational cost simulator using the Taichi programming language for simulating optical tactile sensors, named as <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Tacchi</i> . It reconstructs elastomer deformation using particles, which allows deformed elastomer surfaces to be rendered into tactile images and reveals contact information without suffering from high computational costs. Tacchi facilitates creating realistic tactile images in simulation, e.g., ones that capture wear-and-tear defects on object surfaces. In addition, the proposed Tacchi can be integrated with robotics simulators for a robot system simulation. Experiment results showed that Tacchi can produce images with better similarity to real images and achieved higher Sim2Real accuracy compared to the existing methods. Moreover, it can be connected with MuJoCo and Gazebo with only the requirement of 1G memory space in GPU compared to a computer cluster applied for FEM. With Tacchi, physical robot simulation with optical tactile sensors becomes possible.

Система виртуального моделирования робототехнических систем сельскохозяйственного назначения

Система виртуального моделирования робототехнических систем сельскохозяйственного назначения

Design and experiment of on-orbit assembly ground simulation robot

This paper proposes a space telescope assembly scheme and a ROS-based on-orbit assembly robot simulation system. First, the system fuses the hand-eye camera and the global camera ArUco marked image information to complete the identification and position and pose estimation of the structural parts to be assembled. Then, the pose information is transmitted to the ROS motion control node through Modbus-TCP communication, and the dual-arm robot system is controlled to complete motion planning and obstacle avoidance, arriving at the designated position for precise pick and place. After many simulation experiments of the designed space telescope model assembly scheme, it has been proved that the target object pose estimation algorithm is accurate, and the dual-arm collaborative robot has high position accuracy, which can realize the ground simulation autonomous assembly of large-scale space facilities. The system has certain practical application value with high integration, strong expansibility and good portability.

Mobile Robot Computer Simulation System

The constant development of science and technology, mobile simulation robot become one of the people of tea after a meal, want the simulation robot to human operation level, premise condition clearly understand the principle of the simulation robot, and the mobile robot simulation system the required functionality, and after understanding we should how to realize the function of them. In this paper, the principle, function and realization of the mobile robot simulation system are designed.

Identification of Neural Network Model of Robot to Solve the Optimal Control Problem

To calculate the optimal control, a satisfactory mathematical model of the control object is required. Further, when implementing the calculated controls on a real object, the same model can be used in robot navigation to predict its position and correct sensor data, therefore, it is important that the model adequately reflects the dynamics of the object. Model derivation is often time-consuming and sometimes even impossible using traditional methods. In view of the increasing diversity and extremely complex nature of control objects, including the variety of modern robotic systems, the identification problem is becoming increasingly important, which allows you to build a mathematical model of the control object, having input and output data about the system. The identification of a nonlinear system is of particular interest, since most real systems have nonlinear dynamics. And if earlier the identification of the system model consisted in the selection of the optimal parameters for the selected structure, then the emergence of modern machine learning methods opens up broader prospects and allows you to automate the identification process itself. In this paper, a wheeled robot with a differential drive in the Gazebo simulation environment, which is currently the most popular software package for the development and simulation of robotic systems, is considered as a control object. The mathematical model of the robot is unknown in advance. The main problem is that the existing mathematical models do not correspond to the real dynamics of the robot in the simulator. The paper considers the solution to the problem of identifying a mathematical model of a control object using machine learning technique of the neural networks. A new mixed approach is proposed. It is based on the use of well-known simple models of the object and identification of unaccounted dynamic properties of the object using a neural network based on a training sample. To generate training data, a software package was written that automates the collection process using two ROS nodes. To train the neural network, the PyTorch framework was used and an open source software package was created. Further, the identified object model is used to calculate the optimal control. The results of the computational experiment demonstrate the adequacy and performance of the resulting model. The presented approach based on a combination of a well-known mathematical model and an additional identified neural network model allows using the advantages of the accumulated physical apparatus and increasing its efficiency and accuracy through the use of modern machine learning tools.

Investigation And Simulation Of Dielectric Elastomer Actuators Used In Artificial Muscle Applications

Dielectric Elastomer Actuator (DEA) consists of a thin dielectric elastomer membrane sandwiched between two electrode layers. When low current high voltage is applied to the two conductive layers, opposite loads occur on the surface which tends to pull one another. This voltage application causes thinning in width and expansion in surface area. DEAs are the favourite subject of research due to their low cost advantages, fast response, high energy density, wide deformation and softness. Due to the rigidity of the electric motors and the metal components of the robot, soft-acting robots using DEA are preferred to perform complex tasks instead of conventional robots. Robots with DEA have higher flexibility and better adaptability. Therefore, soft robots are popular topics in robotics research. DEAs are the best candidate materials for next-generation soft robot actuators and artificial muscles. In this study, simulation of robotic system has been realized by using DEAs calculation methods. Simulation results were compared with the data obtained from the application. This study will be the source of future studies on the subject. In the simulation, Matlab 2016 student and Labview Home and Students programs were used.

Using Operator Gaze Tracking to Design Wrist Mechanism for Surgical Robots

This article assessed how surgical robot parameters influenced operator viewpoint during a simulated surgical procedure. Surgical robots are useful tools in minimally invasive surgery. However, even with robots, suturing is difficult because the needle is sometimes obscured by tissue or manipulators and is thus not always visible during the procedure. This is especially true in pediatric surgery, where the surgical environment is smaller than in adult surgery. Hence, surgeons must carefully track the instruments and tissues to understand and predict their current and expected situations. In this article, we used gaze-tracking techniques to analyze the location and timing of the gaze of participants while they manipulated a virtual robotic surgical simulation system. To differentiate between the ideal and actual viewpoint trajectories, we conducted experiments with and without obstacles (i.e., simulated tissue and the manipulator arm). In the obstacle condition, we modulated the wrist length of the manipulator to bring it into view. In the no-obstacle condition, the participants mostly watched the suture needle tip. In the with-obstacle condition, the participants spent less time watching the instruments and more time watching the target point. The amount of time spent watching the target point increased as wrist length increased. Given this tradeoff relationship, we examined the proportion of time the participants spent looking at the instruments or target points by wrist length. We calculated the Pareto solutions and clarified the relationship between wrist length and the watching parts.

Development of BIM-integrated construction robot task planning and simulation system

A major challenge toward construction robotization is a lack of a system that generates detailed behaviors of robots as part of the construction process based on information contained in building information modeling (BIM) and construction schedules. This study extends BIM to incorporate robot task planning and generate detailed motions conducting construction tasks. A prototype was built upon robot operating system (ROS), focusing on generating robot task plans for indoor wall painting. The prototype includes a converter that generates a ROS-compliant world file from industry foundation classes (IFC) file and sub-processes that conduct localization, navigation, and motion planning. A case study was conducted to demonstrate the system's capability to simulate behaviors of a painting robot and evaluate the performance within the context of the construction-related tasks. The case study demonstrates the proposed BIM-leveraged robot task planning can integrate construction and robotics domains to plan operations of autonomous robots in construction projects.

Comparison of numerical methods in code as solvers for simulation of robotic systems

This research introduces the development of the implementation and comparison of algorithms of numeric methods which solve a system of ordinary differential equations, commonly known like solvers. These were applied to a robotic system with 4 grades of freedom in open loop based on the non-linear dynamic model in the joint space. The performance of the robotic system solution simulated on Matlab®/Simulink® with S-Function has been assumed to be the reference criterion to contrast the results that were get from codification of the solvers. Moreover, some inferences were set for each one of the algorythms, for instance, simulation time and computing cost. The analysis of the results lets account the implementation of the code of the numeric methods for simulation purposes, thus, it may aid for the optimization of simulation times and computing cost.