DSP/FPGA-based Controller Architecture for Flexible Joint Robot with Enhanced Impedance Performance

  • J. B. HuangEmail author
  • Z. W. Xie
  • H. Liu
  • K. Sun
  • Y. C. Liu
  • Z. N. Jiang


Some practical issues associated with enhancing the Cartesian impedance performance of flexible joint manipulator are investigated. A digital signal processing/field programmable gate array (DSP/FPGA) structure is proposed to realize the singular perturbation based impedance controller. To increase the bandwidth of torque control and minimize the joint torque ripple, boundary layer system and field-oriented control (FOC) are fully implemented in a FPGA of each joint. The kernel of the hardware system is a peripheral component interface (PCI)-based high speed floating-point DSP for the Cartesian level control, and FPGA for high speed (200 us cycle time) multipoint low-voltage differential signaling (M-LVDS) serial data bus communication between robot Cartesian level and joint level. Experimental results with a four-degree-of-freedom flexible-joint manipulator under constrained-motion task, demonstrate that the controller architecture can enhance the robot impedance performance effectively.


Impedance control DSP FPGA M-LVDS serial data bus Torque ripple Flexible joint 


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Copyright information

© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  • J. B. Huang
    • 1
    Email author
  • Z. W. Xie
    • 1
  • H. Liu
    • 1
    • 2
  • K. Sun
    • 1
  • Y. C. Liu
    • 1
  • Z. N. Jiang
    • 1
  1. 1.Institute of RoboticsHarbin Institute of TechnologyHarbinPeople’s Republic of China
  2. 2.Institute of Robotics and MechatronicsGerman Aerospace Center (DLR)OberpfaffenhofenGermany

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