The von Neumann threshold of self-reproducing systems: theory and application

Robotica ◽  
2011 ◽  
Vol 29 (1) ◽  
pp. 123-135 ◽  
Author(s):  
Pierre T. Kabamba ◽  
Patrick D. Owens ◽  
A. Galip Ulsoy
Keyword(s):  
Error Correction ◽  
Self Assembly ◽  
Degrees Of Freedom ◽  
Minimum Length ◽  
Generation Process ◽  
Robot Arm ◽  
Von Neumann ◽  
Novel Theory ◽  
Reproduction Process ◽  
Simulation Results

SUMMARYThis paper is devoted to the study of systems of entities that are capable of generating other entities of the same kind and, possibly, self-reproducing. The main technical issue addressed is to quantify the requirements that such entities must meet to be able to produce a progeny that is not degenerative, i.e., that has the same reproductive capability as the progenitor. A novel theory that allows an explicit quantification of these requirements is presented. The notion of generation rank of an entity is introduced, and it is proved that the generation process, in most cases, is degenerative in that it strictly and irreversibly decreases the generation rank from parent to descendent. It is also proved that there exists a threshold of rank such that this degeneracy can be avoided if and only if the entity has a generation rank that meets that threshold – this is the von Neumann rank threshold. On the basis of this threshold, an information threshold is derived, which quantifies the minimum amount of information that must be provided to specify an entity such that its descendents are not degenerative. Furthermore, a complexity threshold is obtained, which quantifies the minimum length of the description of that entity in a given language. As an application, self-assembly for a 2 Degrees of Freedom planar robot is considered, and simulation results are presented. A robot arm capable of picking up and placing the components of another arm, in the presence of errors, is considered to have successfully reproduced if these are placed within an allowable tolerance. The example shows that, due to the kinematics of the robot, errors can grow from one generation to the next, until the reproduction process fails eventually. However, error correction (via error sensing and feedback control) can then be used to prevent such degeneracy. The von Neumann generation rank and information thresholds are computed for this example, and are consistent with the simulation results in predicting degeneracy in the case without error correction, and predicting successful self-reproduction in the case with error correction.

The Von Neumann Threshold of Self-Reproducing Systems

2008 ◽  
Author(s):  
Pierre T. Kabamba
Keyword(s):  
Minimum Amount ◽  
Minimum Length ◽  
Generation Process ◽  
Technical Issue ◽  
Von Neumann ◽  
Amount Of Information ◽  
Novel Theory ◽  
Reproductive Capability

This paper is devoted to the study of systems of entities that are capable of generating other entities of the same kind and, possibly, self-reproducing. The main technical issue addressed is to quantify the requirements that such entities must meet to be able to produce a progeny that is not degenerate, i.e., that has the same reproductive capability as the progenitor. A novel theory that allows an explicit quantification of these requirements is presented. The notion of generation rank of an entity is introduced, and it is proved that the generation process, in most cases, is degenerative in that it strictly and irreversibly decreases the generation rank from parent to descendant. It is also proved that there exists a threshold of rank such that this degeneracy can be avoided if and only if the entity has a generation rank that meets that threshold — this is the von Neumann rank threshold. Based on this threshold, an information threshold is derived, which quantifies the minimum amount of information that must be provided to specify an entity such that its descendants are not degenerate. Furthermore, a complexity threshold is obtained, which quantifies the minimum length of the description of that entity in a given language. Examples that illustrate the theory are provided.

Self-Reproducing Machines: Preventing Degeneracy

2006 ◽  
Author(s):  
Patrick D. Owens ◽  
A. Galip Ulsoy
Keyword(s):  
Error Correction ◽  
Kinematic Model ◽  
The Self ◽  
Minimal Amount ◽  
Robot Arm ◽  
Von Neumann ◽  
Component Placement ◽  
Reproduction System ◽  
Reproduction Process ◽  
Constructive Work

Machines produced by humans exhibit insufficient complexity to produce similar machines. As John von Neumann originally postulated, if biological systems are able to successfully reproduce, then there must be some characteristic that we can embed in machines to give them the ability to reproduce. Such a self-reproductive machine, also imbued with the ability to do constructive work, could prove enormously useful to the human race. This paper considers a simple self-reproducing machine, which consists of a 2-DOF, planar robot arm capable of picking up and placing the components of another arm. If the robot places the components within the allowable tolerance, then the original arm has successfully reproduced. An assembly line is constructed, so that a self-reproduction process can proceed along a track. If this process eventually fails because one robot is not capable of assembling another, then the system is said to be degenerate. Otherwise, the system is sustainable. A kinematic model that maps component placement errors from one generation of the robot arm to the next was derived. The system exhibited exponential growth in component placement errors. Thus, this self-reproduction system is degenerate. This system is then augmented to provide error-correction during the assembly process. With the application of error-correction the self-reproduction process is made sustainable. The minimal amount of error-correction required to achieve sustainable self-reproduction was investigated through sensor quantization, and it was shown that the amount of fidelity in the error-correction signal determines the success of the self-reproduction process. This self-reproduction system was also analyzed in the context of Kabamba's Generation Theory, which could predict the results obtained through simulation regarding degeneracy or sustainability.

scholarly journals The modeling of an anthropomorphic robot arm

2018 ◽  
Vol 224 ◽  
pp. 02034 ◽  
Author(s):  
Aleksey Kabanov ◽  
Aleksey Balabanov
Keyword(s):  
Degrees Of Freedom ◽  
Kinematic Model ◽  
Robot Arm ◽  
Modeling Problem ◽  
Kinematics Modeling ◽  
Simulation Results

This paper considers the anthropomorphic manipulator kinematics modeling problem. The considered anthropomorphic robot SAR-400 manipulator with five-fingered gripper has twelve degrees of freedom. In the paper the robot SAR-400 arm kinematic model and the simulation results are presented.

scholarly journals The emerging technology of biohybrid micro-robots: a review

2021 ◽  
Author(s):  
Zening Lin ◽  
Tao Jiang ◽  
Jianzhong Shang
Keyword(s):  
Self Assembly ◽  
Degrees Of Freedom ◽  
High Energy ◽  
Living Cells ◽  
Multiple Degrees Of Freedom ◽  
The Past ◽  
Great Prevalence ◽  
Performance Decline ◽  
High Energy Efficiency ◽  
Living Tissues

Abstract In the past few decades, robotics research has witnessed an increasingly high interest in miniaturized, intelligent, and integrated robots. The imperative component of a robot is the actuator that determines its performance. Although traditional rigid drives such as motors and gas engines have shown great prevalence in most macroscale circumstances, the reduction of these drives to the millimeter or even lower scale results in a significant increase in manufacturing difficulty accompanied by a remarkable performance decline. Biohybrid robots driven by living cells can be a potential solution to overcome these drawbacks by benefiting from the intrinsic microscale self-assembly of living tissues and high energy efficiency, which, among other unprecedented properties, also feature flexibility, self-repair, and even multiple degrees of freedom. This paper systematically reviews the development of biohybrid robots. First, the development of biological flexible drivers is introduced while emphasizing on their advantages over traditional drivers. Second, up-to-date works regarding biohybrid robots are reviewed in detail from three aspects: biological driving sources, actuator materials, and structures with associated control methodologies. Finally, the potential future applications and major challenges of biohybrid robots are explored. Graphic abstract

scholarly journals Error Correction of Multi-Source Weighted-Ensemble Precipitation (MSWEP) over the Lancang-Mekong River Basin

2021 ◽  
Vol 13 (2) ◽  
pp. 312
Author(s):  
Xiongpeng Tang ◽  
Jianyun Zhang ◽  
Guoqing Wang ◽  
Gebdang Biangbalbe Ruben ◽  
Zhenxin Bao ◽  
...  
Keyword(s):  
Error Correction ◽  
River Basin ◽  
Regional Scale ◽  
Mekong River ◽  
Precipitation Data ◽  
Climate Data ◽  
Hydrological Simulation ◽  
Mekong River Basin ◽  
Precipitation Estimation ◽  
Simulation Results

The demand for accurate long-term precipitation data is increasing, especially in the Lancang-Mekong River Basin (LMRB), where ground-based data are mostly unavailable and inaccessible in a timely manner. Remote sensing and reanalysis quantitative precipitation products provide unprecedented observations to support water-related research, but these products are inevitably subject to errors. In this study, we propose a novel error correction framework that combines products from various institutions. The NASA Modern-Era Retrospective Analysis for Research and Applications (AgMERRA), the Asian Precipitation Highly-Resolved Observational Data Integration Towards Evaluation of Water Resources (APHRODITE), the Climate Hazards group InfraRed Precipitation with Stations (CHIRPS), the Multi-Source Weighted-Ensemble Precipitation Version 1.0 (MSWEP), and the Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Climate Data Records (PERSIANN) were used. Ground-based precipitation data from 1998 to 2007 were used to select precipitation products for correction, and the remaining 1979–1997 and 2008–2014 observe data were used for validation. The resulting precipitation products MSWEP-QM derived from quantile mapping (QM) and MSWEP-LS derived from linear scaling (LS) are evaluated by statistical indicators and hydrological simulation across the LMRB. Results show that the MSWEP-QM and MSWEP-LS can better capture major annual precipitation centers, have excellent simulation results, and reduce the mean BIAS and mean absolute BIAS at most gauges across the LMRB. The two corrected products presented in this study constitute improved climatological precipitation data sources, both time and space, outperforming the five raw gridded precipitation products. Among the two corrected products, in terms of mean BIAS, MSWEP-LS was slightly better than MSWEP-QM at grid-scale, point scale, and regional scale, and it also had better simulation results at all stations except Strung Treng. During the validation period, the average absolute value BIAS of MSWEP-LS and MSWEP-QM decreased by 3.51% and 3.4%, respectively. Therefore, we recommend that MSWEP-LS be used for water-related scientific research in the LMRB.

Dynamic Modeling of a High-Dynamic Flight Simulator

2014 ◽  
Vol 687-691 ◽  
pp. 610-615 ◽  
Author(s):  
Hui Liu ◽  
Li Wen Guan
Keyword(s):  
Dynamic Modeling ◽  
Degrees Of Freedom ◽  
Flight Simulator ◽  
Inverse Dynamic ◽  
Dynamic Formulation ◽  
Time Histories ◽  
Rotational Degrees Of Freedom ◽  
High Dynamic ◽  
Euler Approach ◽  
Simulation Results

High-dynamic flight simulator (HDFS), using a centrifuge as its motion base, is a machine utilized for simulating the acceleration environment associated with modern advanced tactical aircrafts. This paper models the HDFS as a robotic system with three rotational degrees of freedom. The forward and inverse dynamic formulations are carried out by the recursive Newton-Euler approach. The driving torques acting on the joints are determined on the basis of the inverse dynamic formulation. The formulation has been implemented in two numerical simulation examples, which are used for calculating the maximum torques of actuators and simulating the time-histories of kinematic and dynamic parameters of pure trapezoid Gz-load command profiles, respectively. The simulation results can be applied to the design of the control system. The dynamic modeling approach presented in this paper can also be generalized to some similar devices.

Cooperation and Null-Space Control of Networked Omni-Directional Mobile Manipulators

2020 ◽  
Author(s):  
Michael John Chua ◽  
Yen-Chen Liu
Keyword(s):  
Degrees Of Freedom ◽  
Null Space ◽  
Kinematic Model ◽  
Mobile Manipulator ◽  
Main Task ◽  
Mobile Manipulators ◽  
Robot Arm ◽  
Task Space ◽  
End Effector ◽  
Mobile Base

Abstract This paper presents cooperation and null-space control for networked mobile manipulators with high degrees of freedom (DOFs). First, kinematic model and Euler-Lagrange dynamic model of the mobile manipulator, which has an articulated robot arm mounted on a mobile base with omni-directional wheels, have been presented. Then, the dynamic decoupling has been considered so that the task-space and the null-space can be controlled separately to accomplish different missions. The motion of the end-effector is controlled in the task-space, and the force control is implemented to make sure the cooperation of the mobile manipulators, as well as the transportation tasks. Also, the null-space control for the manipulator has been combined into the decoupling control. For the mobile base, it is controlled in the null-space to track the velocity of the end-effector, avoid other agents, avoid the obstacles, and move in a defined range based on the length of the manipulator without affecting the main task. Numerical simulations have been addressed to demonstrate the proposed methods.

A 10T Cell Design without Half Select Problem for Bit-Interleaving Architecture in 65nm CMOS

2013 ◽  
Vol 373-375 ◽  
pp. 1607-1611
Author(s):  
Hong Gang Zhou ◽  
Shou Biao Tan ◽  
Qiang Song ◽  
Chun Yu Peng
Keyword(s):  
Error Correction ◽  
Low Voltage ◽  
Cmos Technology ◽  
Soft Error ◽  
Error Correction Codes ◽  
Cell Design ◽  
Low Voltage Operation ◽  
Sram Cell ◽  
Simulation Results ◽  
Nanometer Regime

With the scaling of process technologies into the nanometer regime, multiple-bit soft error problem becomes more serious. In order to improve the reliability and yield of SRAM, bit-interleaving architecture which integrated with error correction codes (ECC) is commonly used. However, this leads to the half select problem, which involves two aspects: the half select disturb and the additional power caused by half-selected cells. In this paper, we propose a new 10T cell to allow the bit-interleaving array while completely eliminating the half select problem, thus allowing low-power and low-voltage operation. In addition, the RSNM and WM of our proposed 10T cell are improved by 21% and nearly one times, respectively, as compared to the conventional 6T SRAM cell in SMIC 65nm CMOS technology. We also conduct a comparison with the conventional 6T cell about the leakage simulation results, which show 14% of leakage saving in the proposed 10T cell.

scholarly journals Strategies of traversing obstacles and the simulation for a forestry chassis

2018 ◽  
Vol 15 (3) ◽  
pp. 172988141877390 ◽  
Author(s):  
Yue Zhu ◽  
Jiangming Kan ◽  
Wenbin Li ◽  
Feng Kang
Keyword(s):  
Multibody Dynamics ◽  
Inclination Angle ◽  
Degrees Of Freedom ◽  
Ride Comfort ◽  
Hydraulic Cylinder ◽  
Single Side ◽  
Simulation Results ◽  
Maximum Inclination ◽  
Three Degrees Of Freedom ◽  
Small Inclination

As to the complicated terrain in forest, forestry chassis with an articulated body with three degrees of freedom and installed luffing wheel-legs (FC-3DOF&LW) is a novel chassis that can surmount obstacles. In addition, the rear frame of FC-3DOF&LW is regarded as the platform to carry equipment. Small inclination angle for rear frame contributes to stability and ride comfort. This article describes the strategy of traversing obstacles and simulation for FC-3DOF&LW that drives in forest terrain. First, key structures of FC-3DOF&LW are briefly introduced, which include articulated structure with three degrees of freedom and luffing wheel-leg. Based on the sketch of luffing wheel-leg, the movement range of luffing wheel-leg is obtained by hydraulic cylinder operation. Second, the strategy of crossing obstacles that are simplified three models of terrain is presented, and the simulation for surmounting obstacles is constructed in multibody dynamics software. The simulation results demonstrate that the inclination angle of rear frame is 18° when slope is 30°. A maximum 12° decrease of inclination angle for rear frame can be acquired when luffing wheel-legs are applied. For traversing obstacles with both sides, the maximum inclination angle of rear frame is about 1.2° and is only 3° for traversing obstacles with single side.

scholarly journals Detachable Robotic Grippers for Human-Robot Collaboration

2021 ◽  
Vol 8 ◽  
Author(s):  
Zubair Iqbal ◽  
Maria Pozzi ◽  
Domenico Prattichizzo ◽  
Gionata Salvietti
Keyword(s):  
Degrees Of Freedom ◽  
Tactile Feedback ◽  
Industrial Robots ◽  
Physical Interaction ◽  
Robot Arm ◽  
Robotic Hands ◽  
End Effector ◽  
External Power ◽  
Self Powered ◽  
Automatic Tool

Collaborative robots promise to add flexibility to production cells thanks to the fact that they can work not only close to humans but also with humans. The possibility of a direct physical interaction between humans and robots allows to perform operations that were inconceivable with industrial robots. Collaborative soft grippers have been recently introduced to extend this possibility beyond the robot end-effector, making humans able to directly act on robotic hands. In this work, we propose to exploit collaborative grippers in a novel paradigm in which these devices can be easily attached and detached from the robot arm and used also independently from it. This is possible only with self-powered hands, that are still quite uncommon in the market. In the presented paradigm not only hands can be attached/detached to/from the robot end-effector as if they were simple tools, but they can also remain active and fully functional after detachment. This ensures all the advantages brought in by tool changers, that allow for quick and possibly automatic tool exchange at the robot end-effector, but also gives the possibility of using the hand capabilities and degrees of freedom without the need of an arm or of external power supplies. In this paper, the concept of detachable robotic grippers is introduced and demonstrated through two illustrative tasks conducted with a new tool changer designed for collaborative grippers. The novel tool changer embeds electromagnets that are used to add safety during attach/detach operations. The activation of the electromagnets is controlled through a wearable interface capable of providing tactile feedback. The usability of the system is confirmed by the evaluations of 12 users.

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