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Objective: This study was aimed to determine the effects of direction and path length on movement time when traversing a constrained path of width, W, in a mouse tracking task. Background: Tracking within constrained paths has been demonstrated to hold in many applications. Movement time and velocity of movement have shown very similar relationships, possibly because of the lack of extreme testing conditions. Most previous research evaluated conditions with only constant path length (A) of movement. Method: A total of 15 participants performed a mouse steering task within a constrained path at various angles. The independent variables were track width (W), path length, and path angle. Movement time was the dependent variable. Results: Analyses showed a significant effect of movement direction on movement time, and the relationship was approximately sinusoidal and symmetrical about the horizontal axis. Path length had a significant effect on speed of movement, which was not that apparent on movement time. At low A/W values, movements appeared to be ballistic. Conclusion: Tracking within constrained paths can be modeled to account for the effect of path angle. Application: Vertical hand movements, especially within constrained paths, may not be ideal from a performance and biomechanical standpoint. The performance curve gradients are a good way to evaluate and standardize the testing of input devices and to define acceptable speeds for various tolerances in computer and industrial tasks that involve angular motions. The results of this experiment will help designers to optimize products and training programs.

[EN] The present paper explores the industrial capabilities of a CAM¿]ROB system implementation based on a commercial CAD/CAM system (NXTM) for an industrial robotic workcell of eight joints, committed to the rapid prototyping of 3D CAD¿]defined models. The workcell consists of a KUKATM KR15/2 manipulator assembled on a linear track and synchronized with a rotary table. A redundancy resolution scheme is developed to deal with the redundancies due to the additional joints of the robot, plus the one from the symmetry axis of the milling tool. During the path tracking, the use of these redundancies is optimized by adjusting two performance criterion vectors related to singularity avoidance and maintenance of a preferred reference posture, as secondary tasks to be done. In addition, two suitable fuzzy inference engines adjust the weight of each joint in these tasks. The developed system is validated in a real prototyping of a carving. ; This research is partially supported by research project DPI2009-14744-C03-01 of the Spanish Government, project PROMETEO 2009/063 of Generalitat Valenciana, and research projects PAID-05-11-2640 and PAID-00-12-SP20120159 of the Universitat Politecnica de Valencia. ; Gracia Calandin, LI.; Andrés De La Esperanza, FJ.; Gracia Calandin, CP. (2012). Automated milling path tracking and CAM-ROB integration for industrial redundant manipulators. International Journal of Advanced Robotic Systems. 9(62):1-8. https://doi.org/10.5772/51101 ; S ; 1 ; 8 ; 9 ; 62 ; Andres, J., Gracia, L., & Tornero, J. (2011). Calibration and control of a redundant robotic workcell for milling tasks. International Journal of Computer Integrated Manufacturing, 24(6), 561-573. doi:10.1080/0951192x.2011.566284 ; Asif, U., & Iqbal, J. (2012). On the Improvement of Multi-Legged Locomotion over Difficult Terrains Using a Balance Stabilization Method. International Journal of Advanced Robotic Systems, 9(1), 1. doi:10.5772/7789 ; Angeles, J. (Ed.). (2003). Fundamentals of Robotic Mechanical Systems: Theory, ...

This researchwas funded by projects TecNM-5654.19-P and DemocratAI PID2020-115570GB-C22. ; In this work, we propose, through the use of population-based metaheuristics, an optimization method that solves the problem of autonomous path tracking using a rear-wheel fuzzy logic controller. This approach enables the design of controllers using rules that are linguistically familiar to human users. Moreover, a new technique that uses three different paths to validate the performance of each candidate configuration is presented. We extend on our previous work by adding two more membership functions to the previous fuzzy model, intending to have a finer-grained adjustment. We tuned the controller using several well-known metaheuristic methods, Genetic Algorithms (GA), Particle Swarm Optimization (PSO), GreyWolf Optimizer (GWO), Harmony Search (HS), and the recent Aquila Optimizer (AO) and Arithmetic Optimization Algorithms. Experiments validate that, compared to published results, the proposed fuzzy controllers have better RMSE-measured performance. Nevertheless, experiments also highlight problems with the common practice of evaluating the performance of fuzzy controllers with a single problem case and performance metric, resulting in controllers that tend to be overtrained. ; TecNM-5654.19-P ; DemocratAI PID2020-115570GB-C22

In the process of the continuous development and improvement of modern military systems, military unmanned vehicles play an important role in field reconnaissance and strategic deployment. In this paper, the precise tracking algorithm of a military unmanned vehicle, based on GPS navigation, is studied. Firstly, the optimal preview point is obtained according to the data points of a differential GPS signal. Secondly, the pure tracking algorithm is used to calculate the demand steering angle, and a variable universe fuzzy sliding mode controller is designed to control the lateral motion of the vehicle, which is verified by the joint simulation platform of Simulink and CarSim, under multiple working conditions. Finally, the actual vehicle is verified by using the Autobox platform. The results show that the lateral motion control of path tracking designed in this paper can achieve an accurate and effective control effect, and has real-time performance for engineering applications.

[EN] A discrete-time sliding mode controller is presented which solves the path tracking problem for a remotely controlled wheeled mobile robot. The control strategy is based on the exact discrete-time model of the mobile robot, including the transport delay induced by the communication network. The proposed controller guarantees asymptotic convergence of the tracking errors. The performance of the controller is evaluated through numerical simulation. ; [ES] En este trabajo se presenta una estrategia de control en tiempo discreto para el seguimiento de trayectorias de un robot móvil tipo (2,0) controlado remotamente. La estrategia de control se desarrolló mediante un enfoque de modos deslizantes, considerando el modelo discreto exacto del vehículo en el cual se incluyen los efectos del retardo de transporte causado por la propagación de las señales sobre una red de comunicación. El esquema de control garantiza el seguimiento de trayectorias predeterminadas obteniéndose convergencia asintótica de los errores de seguimiento. La estrategia propuesta es evaluada mediante una serie de resultados por simulación. ; Trabajo financiado parcialmente por CONACyT, México, mediante el Proyecto 42093. El primer autor se encuentra en comisión de estudios otorgada por la Universidad Militar Nueva Granada, Facultad de Ingeniería, Programa de Ingeniería Mecatrónica, Bogotá, D.C., Colombia ; Niño-Suárez, PA.; Aranda-Bricaire, E.; Velasco-Villa, M. (2007). Control mediante modos deslizantes en tiempo discreto para el seguimiento de trayectorias de un robot móvil. Revista Iberoamericana de Automática e Informática industrial. 4(4):31-38. http://hdl.handle.net/10251/145834 ; OJS ; 31 ; 38 ; 4 ; 4

In advanced industry manufacturing involving robotic operations, the required tasks can be frequently formulated in terms of a path or trajectory tracking. In this paper, an approach based on sliding mode conditioning of a path parametrization is proposed to achieve the greatest tracking speed which is compatible with the robot input constraints (joint speeds). Some distinctive features of the proposal are that: (1) it is completely independent of the robot parameters, and it does not require a priori knowledge of the desired path either, (2) it avoids on-line computations necessary for conventional analytical methodologies, and (3) it can be easily added as a supervisory block to pre-existing path tracking schemes. A sufficient condition (lower bound on desired tracking speed) for the sliding mode regulation to be activated is derived, while a chattering amplitude estimation is obtained in terms of the sampling period and a tunable first-order filter bandwidth. The algorithm is evaluated on the freely accessible 6R robot model PUMA-560, for which a path passing through a wrist singularity is considered to show the effectiveness of the proposal under hard tracking conditions. © 2011 Elsevier B.V. All rights reserved. ; This research is partially supported by DISICOM project PROM-ETEO 2008/088 of Generalitat Valenciana (Spain), research project DPI2008-06731-C02-01 of the Spanish Government (Spain), Technical University of Valencia (Spain), and the Argentinian Government (UNLP 111127, CONICET PIP 112-200801-0, ANPCyT PICT 2007 00535). ; Garelli, F.; Gracia Calandin, LI.; Sala, A.; Albertos Pérez, P. (2011). Sliding mode speed auto-regulation technique for robotic tracking. Robotics and Autonomous Systems. 59(7-8):519-529. https://doi.org/10.1016/j.robot.2011.03.007 ; S ; 519 ; 529 ; 59 ; 7-8