ROBOTICA & MANAGEMENT - Vol. 23, No. 2, December 2018, pp. 3-8
 

A Functional Model of a Serial Redundant Robot


Ovidiu Antonescu *, Mariana Trofimescu **, Constantin Brezeanu ***

* University "Politehnica" of Bucharest,
e-mail: oval33(at)hotmail.com
** Dinu Lipatti High School, Bucharest
e-mail: banitamariana(at)yahoo.com
*** Silcotub S. A. (Tenaris Group) Calarasi
e-mail: br79c(at)yahoo.com

Abstract: The paper presents the mobility calculation, geometry and kinematics of a robot arm. It is a serial robot whose main spatial kinematic chain consists of four revolute joints. Four continuous current electric motors are used for driving the serial robot. We carried out a structural analysis of the robot, which has four mobilities. We have used matrix calculus for the kinematic analysis of the serial robot arm so that we obtained the three Cartesian coordinates of the characteristic points according to the four independent angular parameters. By means of reversed kinematics, when the three coordinates of the end effector point are imposed, we deduced three non-linear equations with four angular unknown parameters, which proves the robot’s redundancy (an extra unknown parameter). Regarding the prehension mechanism, the kinematic schema with two symmetrical parallelograms has been presented, which ensures the circular translational motion of the two fingers. 

Keywords:
 serial robot, kinematic schema, mobility, matrix calculus, end effector.

Full Text

References

[1] Antonescu, O., Antonescu, P.: “Mechanism and Machine Science – course-book”, Politehnica Press, Bucharest, 2016;

[2] Antonescu, P.: “General Formula for the D.O.F. of Complex Structure Manipulators and Robots”, Proceedings of Tenth World Congress on the Theory of Machines and Mechanisms, Oulu, Finland, V. 2, pp. 1067-1072, 1999;

[3] Antonescu, P. et al: “Analysis and Synthesis of Robot Orientation Mmechanisms”, Construcţia de maşini Journal, 54, No. 3, pp. 27-30, 2002;

[4] Antonescu, P., Antonescu, O.: “Methods to Determine the Mobility (d.o.f.) of Complex Structure Manipulators, Mechanisms and Manipulators Journal, Vol. 3, No. 1, pp. 49-54, 2004;

[5] Staretu, I.: “Structural Synthesis and Workspaces of the Serial Kinematic Chains with 7 and 8 Axes for Industrial Robots”, Robotica & Management J., Vol. 18, No. 2, pp. 21-25, 2013;

[6] Filip, V., Mateoiu, M.C.: “Consideration on the Use of Manipulator–Robots in the Laser Beam Processing Technology”, Mechanisms and Manipulators Journal, Vol. 2, No. 1, pp 51-56, 2003;

[7] Nitu, I., Cononovici, S. B., Racovita, W.: “Using the Redundancy of Plane Manipulators to Avoid Restriction Areas”, Mechanisms and Manipulators Journal, Vol. 3, No. 2, pp. 65-72, 2002;

[8] Antonescu, P.: “Mechanisms and Manipulators – applications – project topics”, Printech Publishing House, Bucharest, 2000;

[9] Doroftei, I.: “The Architecture and Kinematics of Robots”, Cermi Publishing House, Iasi, 2002;

[10] Ramirez, D., Kotlarski, J., Ortmaier, T.: “Automatic Generation of Serial Manipulators to be Used in a Combined Structural Geometrical Synthesis”, Mechanisms, Transmissions and Applications, Proceedings of the Third MeTrApp Conference, pp. 239 - 247, 2015;

[11] ***: Instructions - build your own mechanical robot arm, Taiwan. 

[12] Mitu,  N., Paleu,   V.: “Introduction to Matlab - Vol. I”, Laboratory Guidelines, 2008;

[13] Ghinea, M., Fireteanu, V.: „Matlab: Numerical Calculus - Graphics-Applications”, Teora Publishing House, Bucharest, 1998; 

[14] Iatan, I.: „Laboratory Guidelines to Matlab 7.0”, Conspress Publishing House, Bucharest, 2009.