Virtual and rapid prototyping of an underactuated space end effector

A fast and reliable verification of an initial concept is an important need in the field of mechatronics. Usually, the steps for a successful design require multiple iterations involving a sequence of design phases-the initial one and several improvements-and the tests of the resulting prototypes, in a trial and error scheme. Now a day’s software and hardware tools allow for a faster approach, in which the iterations between design and prototyping are by far reduced, even to just one in favorable situation. This work presents the design, manufacturing and testing of a robotic end effector for space applications, realized through virtual prototyping, followed by rapid prototyping realization. The first process allows realizing a mathematical model of the robotic system that, once all the simulations confirm the effectiveness of the design, can be directly used for the rapid prototyping by means of 3D printing. The workflow and the results of the process are described in detail in this paper, showing the qualitative and quantitative evaluation of the performance of both the virtual end effector and the actual physical robotic hand

The Analysis of design and manufacturing tasks using haptic and immersive VR - Some case studies

The use of virtual reality in interactive design and manufacture has been researched extensively but the practical application of this technology in industry is still very much in its infancy. This is surprising as one would have expected that, after some 30 years of research commercial applications of interactive design or manufacturing planning and analysis would be widespread throughout the product design domain. One of the major but less well known advantages of VR technology is that logging the user gives a great deal of rich data which can be used to automatically generate designs or manufacturing instructions, analyse design and manufacturing tasks, map engineering processes and, tentatively, acquire expert knowledge. The authors feel that the benefits of VR in these areas have not been fully disseminated to the wider industrial community and - with the advent of cheaper PC-based VR solutions - perhaps a wider appreciation of the capabilities of this type of technology may encourage companies to adopt VR solutions for some of their product design processes. With this in mind, this paper will describe in detail applications of haptics in assembly demonstrating how user task logging can lead to the analysis of design and manufacturing tasks at a level of detail not previously possible as well as giving usable engineering outputs. The haptic 3D VR study involves the use of a Phantom and 3D system to analyse and compare this technology against real-world user performance. This work demonstrates that the detailed logging of tasks in a virtual environment gives considerable potential for understanding how virtual tasks can be mapped onto their real world equivalent as well as showing how haptic process plans can be generated in a similar manner to the conduit design and assembly planning HMD VR tool reported in PART A. The paper concludes with a view as to how the authors feel that the use of VR systems in product design and manufacturing should evolve in order to enable the industrial adoption of this technology in the future

Virtual prototype-based kinematic modeling and simulation of a multi-mode amphibious robot

The amphibious robot, which has the capability of multi-mode motion, can maneuver diverse environments with high mobility and adaptability. These are employed in the area of reconnaissance, search and rescue operations, and monitoring. The existing amphibious robots have lower maneuverability over the crawling period on uneven and slope surfaces on the land. In this paper, a kinematic model of the amphibious robot based on virtual prototyping is designed for multi-mode locomotion. ADAMS (Automated dynamic analysis of mechanical systems) is a multi-body dynamic solver adopted to build the simulation model for the robot. The novel amphibious robot employs a Rockerbogie mechanism equipped with wheel paddles. The locomotion analysis on land involves straight-going and obstacle negotiation, which is simulated using ADAMS. The simulation analysis result demonstrates increased maneuverability, achieving a robot's velocity of robot 1.6 m/s. Normal forces on the front and rear wheels show equal load distribution, contributing more to the robot’s equilibrium over uneven terrain. The simulation result reflects the accurate kinematic characteristics of the amphibious robot and provides a theoretical basis for developing an algorithm for robot motion control and optimization. Further, this research will concentrate on the kinematic simulation maneuvering in water mode with the wheel paddle

Robot virtual prototype in ADAMS

Tato práce se zabývá vytvořením virtuálního modelu robotu v ADAMS a co-simulačním propojením tohoto modelu s návrhem řízení v Matlab/Simulink. Robotem je segway Pierot vytvořený v rámci předchozích závěrečných prací. Obsahem této práce je vytvoření multi-body modelu, volba pohonu vytvoření co-simulačního propojení a samotná co-simulace.The goal of this work is to create virtual model of robot in ADAMS and co-simulation link between ADAMS and control system in Matlab/Simulink. Robot is segway robot called Pierot, created as the result of past final works. In this work is described creation of robot's multi-body model, choice of the motor, creation of co-simulation link and co-simulation itself.

Automatic generation of robot and manual assembly plans using octrees

This paper aims to investigate automatic assembly planning for robot and manual assembly. The octree decomposition technique is applied to approximate CAD models with an octree representation which are then used to generate robot and manual assembly plans. An assembly planning system able to generate assembly plans was developed to build these prototype models. Octree decomposition is an effective assembly planning tool. Assembly plans can automatically be generated for robot and manual assembly using octree models. Research limitations/implications - One disadvantage of the octree decomposition technique is that it approximates a part model with cubes instead of using the actual model. This limits its use and applications when complex assemblies must be planned, but in the context of prototyping can allow a rough component to be formed which can later be finished by hand. Assembly plans can be generated using octree decomposition, however, new algorithms must be developed to overcome its limitations

Virtual Prototyping, Identification and Control of a Twin Rotor with 3DOF

This paper presents a methodology for identification of the physical characteristics, generation of the mathematical model through virtual prototyping and control of the didactic plant of a twin rotor. In the identification of the physical characteristics, the centers of mass and moments of inertia of the twin rotor parts were identified separately, by means of an easel designed for such task. Still in the identification of the physical characteristics, the equation that relates the applied voltage in the direct current motor with the thrust force produced by the propellers was obtained. The mathematical model of the twin rotor was obtained by means of the identification of the physical characteristics allied to the virtual prototyping with the aid of ADAMS and SolidWorks software. The implemented control system uses state feedback and complete eigenstructure assignment. The ease and usefulness of the proposed methodology was presented through the plant instrumentation, simulation and control in MATLAB/Simulink environment

DYNAMIC ANALYSIS OF THE RIGID-FLEXIBLE EXCAVATOR MECHANISM BASED ON VIRTUAL PROTOTYPE

In this paper, the excavator’s dynamic performance is considered together with the study of its trajectory, stress distribution and vibration. Many researchers have focused their study on the kinematics principle while a few others focused their work on dynamic performance, especially the vibration analysis. Previous studies of dynamic performance analysis have ignored the vibration effects. To address these challenges, the rigid-flexible coupling model of the excavator attachment is established and carried out based on virtual prototyping in this study. The dipper handle, the boom and the hoist rope are modeled as a flexible multi-body system for structural strength. The other components are modeled as a rigid multi-body system to catch the dynamic characteristics. The results show that the number of flexible bodies has little effect on the excavation trajectory. The maximum stress determined for the dipper handle and the boom are 96.45 MPa and 212.24 MPa, respectively. The dynamic performance of the excavator is greatly influenced by the clearance and is characterized by two phases: as the clearance decreases, the dynamic response decreases at first and then increases