scholarly journals Vision-based kinematic analysis of the Delta robot for object catching

Robotica ◽  
2021 ◽  
pp. 1-21
Author(s):  
Sachin Kansal ◽  
Sudipto Mukherjee
Keyword(s):  
Kinematic Analysis ◽  
Inverse Kinematics ◽  
Least Square Method ◽  
Least Square ◽  
Kinematic Parameters ◽  
Implicit Model ◽  
Implicit Equations ◽  
Sensor Module ◽  
Fixed Base ◽  
Projection Error

SUMMARY This paper proposes a vision-based kinematic analysis and kinematic parameters identification of the proposed architecture, designed to perform the object catching in the real-time scenario. For performing the inverse kinematics, precise estimation of the link lengths and other parameters needs to be present. Kinematic identification of Delta based upon Model10 implicit model with ten parameters using the iterative least square method is implemented. The loop closure implicit equations have been modelled. In this paper, a vision-based kinematic analysis of the Delta robots to do the catching is discussed. A predefined library of ArUco is used to get a unique solution of the kinematics of the moving platform with respect to the fixed base. The re-projection error while doing the calibration in the vision sensor module is 0.10 pixels. Proposed architecture interfaced with the hardware using the PID controller. Encoders are quadrature and have a resolution of 0.15 degrees embedded in the experimental setup to make the system closed-loop (acting as feedback unit).

Kinematic Analysis and Dimensional Synthesis of a New 2R1T Parallel Kinematic Machine

2018 ◽  
Author(s):  
Lingmin Xu ◽  
Xubiao Zhu ◽  
Wei Ye ◽  
Qinchuan Li ◽  
Qiaohong Chen
Keyword(s):  
Kinematic Analysis ◽  
Inverse Kinematics ◽  
Parallel Kinematic Machine ◽  
Dimensional Synthesis ◽  
Transmission Index ◽  
Fixed Base ◽  
Prismatic Joints ◽  
Force Transmissibility ◽  
Parallel Kinematic ◽  
Local Transmission

This paper deals with the kinematic analysis and dimensional synthesis of a new 2R1T (R: rotation, T: translation) parallel kinematic machine (PKM). This is a 2PRU-UPR (P, R, U standing for prismatic, revolute and universal joint, respectively) PKM that is actuated by three actuated prismatic joints, two of which are mounted on the fixed base to reduce the movable mass. Firstly, the mobility and inverse kinematics of the 2PRU-UPR PKM are proposed. And then the motion/force transmissibility is evaluated by the local transmission index and good transmission workspace. Moreover, the singular configurations are obtained according to the motion/force transmissibility. Dimensional synthesis is carried out based on the GTW, and the optimized architectural parameters with good GTW are obtained. Finally, a prototype based on the optimized parameters has been developed, which has great potential in machining workpieces with curved surfaces.

Study on Identification Method of Geometric Parameter Errors of 6-DOF Parallel Machine Tool

2011 ◽  
Vol 299-300 ◽  
pp. 1171-1177
Author(s):  
Peng Shan ◽  
Li Yang Xie ◽  
Jia Liang Shi ◽  
Ming Fei Sun
Keyword(s):  
Geometric Parameter ◽  
Inverse Kinematics ◽  
Parallel Machines ◽  
Parallel Machine ◽  
Least Square ◽  
Kinematic Parameters ◽  
Simulation Results ◽  
Parallel Machine Tool ◽  
Linear Least Square ◽  
Identification Model

A computational model for position and posture error of 6-DOF parallel machines is proposed based on D-H transformation matrix and the inverse kinematics. The model is used to construct a linear least-square identification model for geometric parameter errors. Error identification program and compensation method are also presented. Simulation results indicate that the effects on position and posture of machines are almost equivalent from calculated least-square solution and from real values. The pose error of moving platform can be decreased up to 90% if error compensation is performed by modifying the input kinematic parameters of driving joints.

Optimal Weighted Least Square Data Fusion Method for Redundant IMU Based on Calculation of Measurement Error

2012 ◽  
Vol 241-244 ◽  
pp. 149-155
Author(s):  
Chuan Xing ◽  
Hai Zhang
Keyword(s):  
Measurement Error ◽  
Data Fusion ◽  
Measurement Errors ◽  
Least Square Method ◽  
Least Square ◽  
Weighted Least Square ◽  
Weighted Matrix ◽  
Measurement Results ◽  
The Difference ◽  
Projection Error

A dodecahedron non-orthogonal redundant IMU configuration was selected as model. To improve fusion accuracy, we proposed an effective calculation method for measurement errors based on the correlation between measurement errors and fusion errors. The method considered the difference between traditional data fusion vector’s projection and measurement results, and then made a conversion from projection error to measurement error. Combined with optimal weighted least square method, measurement error was used to generate an optimal weighted matrix, and this made data fusion errors minimum. Simulations also proved that the fusion result of this method is more accurate than the result of traditional method.

Identification and Compensation of a Robot Kinematic Parameter for Positioning Accuracy Improvement

Robotica ◽  
1991 ◽  
Vol 9 (1) ◽  
pp. 99-105 ◽  
Author(s):  
D. H. Kim ◽  
K. H. Cook ◽  
J. H. Oh
Keyword(s):  
Error Function ◽  
Least Square Method ◽  
Kinematic Parameter ◽  
Least Square ◽  
Joint Angles ◽  
Kinematic Parameters ◽  
Accuracy Improvement ◽  
Coordinate Frames ◽  
Identification Method ◽  
Value Decomposition

SUMMARYThis paper presents a simple identification method of the actual kinematic parameters for a robot with parallel joints. It is known that Denavit–Hartenberg's coordinate System is not useful for nearly parallel joints. In this paper, the coordinate frames are reassigned to model the kinematic parameter between nearly parallel joints by four parameters. The proposed identification method uses a straight ruler about 1 m long. A robot hand is placed by using a teaching pendant at the prescribed points on the ruler, and the corresponding error function is defined. The identified kinematic parameters, which make the error function zero, are obtained by the iterative least square method based on the singular value decomposition. In the compensation of joint angles, only the position is considered because the usual applications of robot do not require a precise orientation control.

scholarly journals Terrain Feature Estimation Method for a Lower Limb Exoskeleton Using Kinematic Analysis and Center of Pressure

Sensors ◽  
2019 ◽  
Vol 19 (20) ◽  
pp. 4418 ◽  
Author(s):  
Myounghoon Shim ◽  
Jong In Han ◽  
Ho Seon Choi ◽  
Seong Min Ha ◽  
Jung-Hoon Kim ◽  
...  
Keyword(s):  
Lower Limb ◽  
Kinematic Analysis ◽  
Center Of Pressure ◽  
Contact Point ◽  
Estimation Method ◽  
Least Square Method ◽  
Least Square ◽  
Estimation Accuracy ◽  
Lower Limb Exoskeleton ◽  
Contact Points

While controlling a lower limb exoskeleton providing walking assistance to wearers, the walking terrain is an important factor that should be considered for meeting performance and safety requirements. Therefore, we developed a method to estimate the slope and elevation using the contact points between the limb exoskeleton and ground. We used the center of pressure as a contact point on the ground and calculated the location of the contact points on the walking terrain based on kinematic analysis of the exoskeleton. Then, a set of contact points collected from each step during walking was modeled as the plane that represents the surface of the walking terrain through the least-square method. Finally, by comparing the normal vectors of the modeled planes for each step, features of the walking terrain were estimated. We analyzed the estimation accuracy of the proposed method through experiments on level ground, stairs, and a ramp. Classification using the estimated features showed recognition accuracy higher than 95% for all experimental motions. The proposed method approximately analyzed the movement of the exoskeleton on various terrains even though no prior information on the walking terrain was provided. The method can enable exoskeleton systems to actively assist walking in various environments.

scholarly journals Carbon Dioxide Sensor Module Based on NDIR Technology

Micromachines ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 845
Author(s):  
Libing Zhou ◽  
Yaoyi He ◽  
Qing Zhang ◽  
Lei Zhang
Keyword(s):  
Light Propagation ◽  
Detection System ◽  
Coupling Efficiency ◽  
Least Square Method ◽  
Least Square ◽  
Compensation Algorithm ◽  
Dual Channel ◽  
Sensor Module ◽  
Gas Chamber ◽  
Channel Type

In this paper, a gas detection system with an environmental compensation algorithm based on nondispersive infrared (NDIR) technology was designed. The prepared infrared pyroelectric detector was a dual-channel type based on the lithium tantalate (LiTaO3) wafer. The design of the optical gas chamber adopted a combination of two ellipsoids and a spherical top surface, which not only enhanced the coupling efficiency of the light propagation but also facilitated the miniaturization of the sensor module. In addition to this, a temperature and humidity compensation algorithm based on the least square method was proposed to make the measurement accuracy up to ±0.9% full scale (FS).

Direct Assessment of Effective Renal Plasma Flow from Renoscintigraphy with a Gamma Camera and an On-Line Computer

1981 ◽  
Vol 20 (06) ◽  
pp. 274-278
Author(s):  
J. Liniecki ◽  
J. Bialobrzeski ◽  
Ewa Mlodkowska ◽  
M. J. Surma
Keyword(s):  
Count Rate ◽  
Renal Plasma Flow ◽  
Early Period ◽  
Least Square Method ◽  
Least Square ◽  
Uptake Coefficient ◽  
Positive Linear Correlation ◽  
On Line ◽  
Best Fit ◽  
Plasma Activity

A concept of a kidney uptake coefficient (UC) of 131I-o-hippurate was developed by analogy from the corresponding kidney clearance of blood plasma in the early period after injection of the hippurate. The UC for each kidney was defined as the count-rate over its ROI at a time shorter than the peak in the renoscintigraphic curve divided by the integral of the count-rate curve over the "blood"-ROI. A procedure for normalization of both curves against each other was also developed. The total kidney clearance of the hippurate was determined from the function of plasma activity concentration vs. time after a single injection; the determinations were made at 5, 10, 15, 20, 30, 45, 60, 75 and 90 min after intravenous administration of 131I-o-hippurate and the best-fit curve was obtained by means of the least-square method. When the UC was related to the absolute value of the clearance a positive linear correlation was found (r = 0.922, ρ > 0.99). Using this regression equation the clearance could be estimated in reverse from the uptake coefficient calculated solely on the basis of the renoscintigraphic curves without blood sampling. The errors of the estimate are compatible with the requirement of a fast appraisal of renal function for purposes of clinical diagknosis.

PENGARUH KNOWLEDGE MANAGEMENT, KOMPETENSI, MOTIVASI TERHADAP KINERJA KARYAWAN

2015 ◽  
Vol 5 (2) ◽  
pp. 1
Author(s):  
Miftahol Arifin
Keyword(s):  
Knowledge Management ◽  
Linear Regression ◽  
Significant Influence ◽  
Employee Performance ◽  
Least Square Method ◽  
Least Square ◽  
Analysis Tool ◽  
Ordinary Least Square ◽  
Competence Motivation ◽  
Performance Analyze

The purpose of this research is to analyze the influence of knowledge management on employee performance, analyze the effect of competence on employee performance, analyze the influence of motivation on employee performance). In this study, samples taken are structural employees PT.centris Kingdom Taxi Yogyakarta. The analysis tool in this study using multiple linear regression with Ordinary Least Square method (OLS). The conclusion of this study showed that the variables of knowledge management has a significant influence on employee performance, competence variables have an influence on employee performance, motivation variables have an influence on employee performance, The analysis showed that the variables of knowledge management, competence, motivation on employee performance.Keywords: knowledge management, competence, motivation, employee performance.

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