Project TitleTri-pyramid Robot: a novel 3-degree-of-freedom translational parallel manipulator
Track Code2013-068
Short Description

A novel 3-DOF translational parallel manipulator with high output stiffness and accuracy



Northwestern’s researchers have developed a novel 3-DOF (Degree of Freedom) translational manipulator called tri-pyramid robot. Capable of manipulating an objective in space by generating translational output in three directions, the 3-DOF translational manipulators are widely used in industry. However, most current 3-DOF translational manipulators have limited output stiffness and accuracy. To overcome these disadvantages, the tri-pyramid robot is developed using novel topology to achieve high structure load/weight-ratio and output accuracy. With the improved operating speed, output stiffness and precision compared with existing systems, the tri-pyramid robot is promising for various industrial applications, such as machining, precision positioning, and operations of robotic arms.

Figure: Structure design of the tri-pyramid robot

TagsINSTRUMENTATION: manufacturing, MANUFACTURE:process
Posted DateJan 7, 2015 2:47 PM


Zeng Qiang*

Kornel F Ehmann

Jian Cao


  • High stiffness/accuracy fabrication machines, such as milling or metal forming
  • High-speed pick and place operations
  • Precision positioning
  • Robotic arms


  • High output stiffness and accuracy
  • High operating speed and dexterity
  • High load/weight ratio
  • Free of motion singularity


Zeng Q, Ehmann KF,  Cao J (2014) Tri-pyramid robot: design and kinematic analysis of a 3-DOF translational parallel manipulator, Robotics and Computer-Integrated Manufacturing, 30: 648-657.

Zeng Q, Ehmann KF,  Cao J (2014) Tri-pyramid robot: stiffness modeling of a 3-DOF translational parallel manipulator, Robotica, doi:10.1017/S0263574714001520.

IP Status

US provisional patent application has been filed

Marketing Contact

Arjan Quist, PhD

Invention Associate

(p) 847-467-0305



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AQ 2013-068 Zeng.pdf None Download
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