Robot Wrist Configurations, Mechanisms and Kinematics

  • A. Romiti
  • T. Raparelli
  • M. Sorli
Part of the Schriftenreihe der Wissenschaftlichen Landesakademie für Niederösterreich book series (AKADNIEDERÖSTER)


This paper discusses a general method for determining the kinematic performance of spherical robot wrists. Different wrist types considered include R-P-R (roll-pitch-roll) and P-Y-R (pitch-yaw-roll) wrists. Singularity conditions are indicated for both cases. For R-P-R wrists, singularity is defined by the ratio of the angular velocity of each motor to the velocity around the degeneracy axis. For P-Y-R wrists, singularity is identified both by analyzing the Jacobian matrix and by analyzing the relative velocities of the wrist components.


Angular Velocity Pitch Motion Bevel Gear Robotic Research Degeneracy Level 
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Copyright information

© Springer-Verlag/Wien 1994

Authors and Affiliations

  • A. Romiti
    • 1
  • T. Raparelli
    • 1
  • M. Sorli
    • 2
  1. 1.Department of MechanicsPolitecnico di TorinoItaly
  2. 2.Department of Industrial EngineeringUniversity of Cassino (FR)Italy

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