scholarly journals Balancing of the Orthoglide Taking into Account Its Varying Payload

Robotics ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 30
Author(s):  
Jing Geng ◽  
Vigen Arakelian ◽  
Damien Chablat ◽  
Philippe Lemoine
Keyword(s):  
Total Mass ◽  
Center Of Mass ◽  
Inertial Force ◽  
Industrial Robots ◽  
Suggested Approach ◽  
Counter Rotation ◽  
Mechanical Methods ◽  
Robot Systems ◽  
Inertial Moment ◽  
Supporting Frame

For fast-moving robot systems, the fluctuating dynamic loads transmitted to the supporting frame can excite the base and cause noise, wear, and fatigue of mechanical components. By reducing the shaking force completely, the dynamic characteristics of the robot system can be improved. However, the complete inertial force and inertial moment balancing can only be achieved by adding extra counterweight and counter-rotation systems, which largely increase the total mass, overall size, and complexity of robots. In order to avoid these inconveniences, an approach based on the optimal motion control of the center of mass is applied for the shaking force balancing of the robot Orthoglide. The application of the “bang–bang” motion profile on the common center of mass allows a considerable reduction of the acceleration of the total mass center, which results in the reduction of the shaking force. With the proposed method, the shaking force balancing of the Orthoglide is carried out, taking into account the varying payload. Note that such a solution by purely mechanical methods is complex and practically inapplicable for industrial robots. The simulations in ADAMS software validate the efficiency of the suggested approach.

scholarly journals Shaking Force Balancing of the Delta Robot

2020 ◽  
Author(s):  
Jing Geng ◽  
Vigen Arakelian ◽  
Damien Chablat
Keyword(s):  
Control System ◽  
Total Mass ◽  
Robot Control ◽  
Center Of Mass ◽  
Mass Center ◽  
Motion Generation ◽  
Suggested Approach ◽  
Mass Redistribution ◽  
Delta Robot ◽  
Straight Lines

Abstract The paper deals with the shaking force balancing of the DELTA robot. The balancing of the shaking force of the DELTA robot is carried out through the center of mass acceleration minimization. The trajectories of the total mass center of moving links are defined as straight lines between the initial and final positions of the platform. Then, the motion between these positions are parameterized with “bang-bang” motion profiles. Such a motion generation allows the reduction of the maximal value of the center of mass acceleration and, consequently, leads to the reduction in the shaking force. A main advantage of this method is its simplicity and versatility. It is carried out without any modification of mass redistribution of the initial robot structure, i.e. without adding counterweights. In the case of changing trajectories or payloads, it is just necessary to provide the initial and final positions of the platform, calculate the input parameters according to the proposed method and implemented them in the robot control system. Numerical simulations illustrate the efficiency of the suggested approach.

scholarly journals Modeling, comparison and evaluation of one-DOF six-bar bioinspired jumping leg mechanisms

2021 ◽  
Vol 13 (2) ◽  
pp. 168781402199295
Author(s):  
Ziqiang Zhang ◽  
Qi Yang ◽  
Xingkun Liu ◽  
Chuanzhong Zhang ◽  
Jinnong Liao
Keyword(s):  
Center Of Mass ◽  
Principal Component ◽  
Analysis Method ◽  
Index Distribution ◽  
Inertial Moment ◽  
Structure Index ◽  
Mean And Variance ◽  
Research Objects ◽  
Leg Mechanisms ◽  
Selection Of

One degree-of-freedom (DOF) jumping leg has the advantages of simple control and high stiffness, and it has been widely used in bioinspired jumping robots. Compared with four-bar jumping leg, six-bar jumping leg mechanism can make the robot achieve more abundant motion rules. However, the differences among different configurations have not been analyzed, and the choice of configurations lacks basis. In this study, five Watt-type six-bar jumping leg mechanisms were selected as research objects according to the different selection of equivalent tibia, femur and trunk link, and a method for determining the dimension of the jumping leg was proposed based on the movement law of jumping leg of locust in take-off phase. On this basis, kinematics indices (sensitivity of take-off direction angle and trunk attitude angle), dynamics indices (velocity loss, acceleration fluctuation, and mean and variance of total inertial moment) and structure index (distribution of center of mass) were established, and the differences of different configurations were compared and analyzed in detail. Finally, according to the principal component analysis method, the optimal selection method for different configurations was proposed. This study provides a reference for the design of one DOF bioinspired mechanism.

scholarly journals 2dF Spectroscopy of Globular Clusters in M104

2005 ◽  
Vol 13 ◽  
pp. 199-199
Author(s):  
Terry Bridges ◽  
Steve Zepf ◽  
Katherine Rhode ◽  
Ken Freeman
Keyword(s):  
Dark Matter ◽  
Strong Evidence ◽  
Total Mass ◽  
Globular Clusters ◽  
Total Sample ◽  
Dark Matter Halo ◽  
Large Radius ◽  
Counter Rotation ◽  
Spatial Coverage

AbstractWe have found 56 new globular clusters in M104 from 2dF multi-fiber spectroscopy, doubling the number of confirmed clusters, and extending the spatial coverage to 50 kpc radius. We find no significant rotation in the total sample, or for subsets split by color or radius. However, there are hints that the blue clusters have a higher rotation than the red clusters, and for counter-rotation of clusters at large radius. We find a total mass of M ~ 1 × 1012M⊙ and a (M/L)B =30 out to 50 kpc radius, which is strong evidence for a dark matter halo in M104.

Herstellerneutrale Programmierung von Robotern*/Manufacturer-independent programming of robots - A software architecture concept for controlling and programming heterogeneous robotic systems

2017 ◽  
Vol 107 (09) ◽  
pp. 594-599
Author(s):  
A. Magaña ◽  
G. Prof. Reinhart
Keyword(s):  
Software Architecture ◽  
Industrial Robots ◽  
Robotic Systems ◽  
Key Technology ◽  
Robot Systems ◽  
And Control

Industrieroboter sind zu einer Schlüsseltechnologie in der Produktion geworden. Mit dem steigenden Einsatz von diversen Robotersystemen wächst das Bedürfnis, deren Kompatibilität zu steigern. Heutzutage gibt es keine Technologie in der Industrie, die eine standardisierte Programmierung und Steuerung von verschiedenen Robotersystemen gewährleisten kann. Dieser Fachbeitrag präsentiert ein einheitliches Konzept, welches die Anwendung von herstellerneutralen Roboterapplikationen ermöglicht.   Industrial robots have become a key technology in production. The increasing use of various robotic systems, raises the need to enhance their compatibilit.y Nowadays, there is no technology in the industry to guarantee a standardized programming and control of different robot systems. This article presents a concept enabling the use of manufacturer-independent robot applications.

Precision Evaluation of NeXus, a Custom Multi-Robot System for Microsystem Integration

2021 ◽  
Author(s):  
Danming Wei ◽  
Alireza Tofangchi ◽  
Andriy Sherehiy ◽  
Mohammad Hossein Saadatzi ◽  
Moath Alqatamin ◽  
...  
Keyword(s):  
Degrees Of Freedom ◽  
Industrial Robot ◽  
Sensor Arrays ◽  
Industrial Robots ◽  
Element Analysis ◽  
Product Packaging ◽  
Precision Evaluation ◽  
High Efficient ◽  
Supporting Frame ◽  
Microsystem Integration

Abstract Industrial robots, as mature and high-efficient equipment, have been applied to various fields, such as vehicle manufacturing, product packaging, painting, welding, and medical surgery. Most industrial robots are only operating in their own workspace, in other words, they are floor-mounted at the fixed locations. Just some industrial robots are wall-mounted on one linear rail based on the applications. Sometimes, industrial robots are ceiling-mounted on an X-Y gantry to perform upside-down manipulation tasks. The main objective of this paper is to describe the NeXus, a custom robotic system that has been designed for precision microsystem integration tasks with such a gantry. The system tasks include assembly, bonding, and 3D printing of sensor arrays, solar cells, and microrobotic prototypes. The NeXus consists of a custom designed frame, providing structural rigidity, a large overhead X-Y gantry carrying a 6 degrees of freedom industrial robot, and several other precision positioners and processes. We focus here on the design and precision evaluation of the overhead ceiling-mounted industrial robot of NeXus and its supporting frame. We first simulated the behavior of the frame using Finite Element Analysis (FEA), then experimentally evaluated the pose repeatability of the robot end-effector using three different types of sensors. Results verify that the performance objectives of the design are achieved.

Supporting Semantic Capture During Kinesthetic Teaching of Collaborative Industrial Robots

2018 ◽  
Vol 12 (01) ◽  
pp. 167-186 ◽  
Author(s):  
Maj Stenmark ◽  
Mathias Haage ◽  
Elin A. Topp ◽  
Jacek Malec
Keyword(s):  
Domain Knowledge ◽  
Semantic Information ◽  
Industrial Robot ◽  
Semantic Context ◽  
Industrial Robots ◽  
Teaching Mode ◽  
Language Support ◽  
Semantic Data ◽  
Robot Systems ◽  
System Knowledge

Industrial robot systems being deployed today do not contain domain knowledge to aid robot operators in setup and operational use. To gather such knowledge in a robotic context requires mechanisms for entering and capturing semantic data. Such mechanisms would allow a system to gradually build a working vocabulary while interacting with the environment and operators, valuable for the bootstrapping system knowledge and ensuring the data collection over time. This paper presents a prototype user interface that assists the kinesthetic teaching mode of a collaborative industrial robot, allowing for the capture of semantic information while working with the robot in day-to-day use. Two modalities, graphical point-and-click and natural language, support capture of semantic context and the building of a working vocabulary of the environment while modifying or creating robot programs. A semantic capture experiment illustrates the approach.

scholarly journals Investigating the Influence of Shaft Balance Point on Clubhead Speed: A Simulation Study

Proceedings ◽  
2020 ◽  
Vol 49 (1) ◽  
pp. 156
Author(s):  
William McNally ◽  
John McPhee
Keyword(s):  
Total Mass ◽  
Center Of Mass ◽  
Golf Club ◽  
Physical Interaction ◽  
Balance Point ◽  
Mass Distributions ◽  
Biomechanical Models ◽  
Significant Difference ◽  
The Mean ◽  
Simulation Results

In this study, a dynamic golfer model was used to investigate the influence of the golf shaft’s balance point (i.e., center of mass) on the generation of clubhead speed. Three hypothetical shaft designs having different mass distributions, but the same total mass and stiffness, were proposed. The golfer model was then stochastically optimized 100 times using each shaft. A statistically significant difference was found between the mean clubhead speeds at impact (p < 0.001), where the clubhead speed increased as the balance point moved closer to the grip. When comparing the two shafts with the largest difference in balance point, a 1.6% increase in mean clubhead speed was observed for a change in balance point of 18.8 cm. The simulation results have implications for shaft design and demonstrate the usefulness of biomechanical models for capturing the complex physical interaction between the golfer and golf club.

scholarly journals Analysis of flexible supported industrial robot on terminal accuracy

2018 ◽  
Vol 15 (4) ◽  
pp. 172988141879302
Author(s):  
Liping Wang ◽  
Lian Chen ◽  
Zhufeng Shao ◽  
Liwen Guan ◽  
Li Du
Keyword(s):  
Vibration Suppression ◽  
Industrial Robot ◽  
Reaction Force ◽  
Industrial Robots ◽  
High Quality ◽  
Flexible Support ◽  
Performance Requirements ◽  
Large Structures ◽  
Robot Systems ◽  
Motion Range

To meet comprehensive performance requirements of large workspace, lightweight, and low energy consumption, and flexible supported industrial robots emerge, which are usually composed of a six-degrees-of-rotational-freedom (6R) industrial robot and a flexible support. Flexible support greatly expands the motion range of the attached industrial robot. Flexible supported industrial robots have been adopted in surface coating of large structures such as aircrafts and rockets. However, the rigid–flexible coupling exists in these robot systems. When the industrial robot moves, the reaction force and torque of the robot disturb the flexible support and introduce vibration, which may result in the deterioration of the system’s terminal accuracy. This study focuses on both the robot body accuracy and system vibration suppression to improve the terminal accuracy of the flexible supported industrial robot. Firstly, based on kinematics analysis, accuracy of the industrial robot is investigated with the local conditioning index. Then, reaction force and torque ellipsoids are proposed with the deduced dynamic model to evaluate disturbances that the industrial robot applies to the flexible support. Considering these two aspects, the high-quality workspace of the flexible supported industrial robot is established. Numerical simulations show that reaction force and torque are effectively limited in the high-quality workspace, which greatly reduce the vibration energy and improve the terminal accuracy of the system.

scholarly journals Features of description of composite system’s motion in twist-deformed spacetime

2019 ◽  
Vol 34 (09) ◽  
pp. 1950071 ◽  
Author(s):  
Kh. P. Gnatenko
Keyword(s):  
Relative Motion ◽  
Equivalence Principle ◽  
Total Mass ◽  
Composite System ◽  
Center Of Mass ◽  
Weak Equivalence ◽  
Weak Equivalence Principle ◽  
Commutation Relations ◽  
Individual Particles ◽  
Inverse Proportionality

Composite system made of N particles is considered in twist-deformed spacetime. It is shown that in the space the motion of the center-of-mass of the system depends on the relative motion. Influence of deformation on the motion of the center-of-mass of composite system is less than on the motion of individual particles and depends on the system’s composition. We conclude that if we consider commutation relations for coordinates of a particle to be inversely proportional to its mass, the commutation relations for coordinates of composite system do not depend on its composition and are proportional inversely to system’s total mass, besides the motion of the center-of-mass is independent of the relative motion. In addition, we find that inverse proportionality of parameters of noncommutativity to mass is important for considering coordinates in twist-deformed space as kinematic variables and for preservation of the weak equivalence principle.

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