A new computational structure for real-time dynamics

Izaguirre, A; Hashimoto, Minoru

doi:10.1177/027836499201100407

Title: A new computational structure for real-time dynamics

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Abstract

The authors present an efficient structure for the computation of robot dynamics in real time. The fundamental characteristic of this structure is the division of the computation into a high-priority synchronous task and low-priority background tasks, possibly sharing the resources of a conventional computing unit based on commercial microprocessors. The background tasks compute the inertial and gravitational coefficients as well as the forces due to the velocities of the joints. In each control sample period, the high-priority synchronous task computes the product of the inertial coefficients by the accelerations of the joints and performs the summation of the torques due to the velocities and gravitational forces. Kircanski et al. (1986) have shown that the bandwidth of the variation of joint angles and of their velocities is an order of magnitude less than the variation of joint accelerations. This result agrees with the experiments the authors have carried out using a PUMA 260 robot. Two main strategies contribute to reduce the computational burden associated with the evaluation of the dynamic equations. The first involves the use of efficient algorithms for the evaluation of the equations. The second is aimed at reducing the number of dynamic parameters by identifying beforehand the linearmore »« less

Authors:

Izaguirre, A ^[1]; Hashimoto, Minoru ^[2]

New Jersey Inst. of Tech., Newark (United States)
Univ. of Electrocommunications, Tokyo (Japan)

Publication Date:: Sat Aug 01 00:00:00 EDT 1992

OSTI Identifier:: 6997668

Resource Type:: Journal Article

Journal Name:: International Journal of Robotics Research; (United States)

Additional Journal Information:: Journal Volume: 11:4; Journal ID: ISSN 0278-3649

Country of Publication:: United States

Language:: English

Subject:: 42 ENGINEERING; MANIPULATORS; CONTROL; COMPUTER CALCULATIONS; COMPUTERIZED CONTROL SYSTEMS; POSITIONING; REAL TIME SYSTEMS; SYNCHRONIZATION; TASK SCHEDULING; CONTROL SYSTEMS; DATA PROCESSING; EQUIPMENT; LABORATORY EQUIPMENT; MATERIALS HANDLING EQUIPMENT; ON-LINE CONTROL SYSTEMS; ON-LINE SYSTEMS; PROCESSING; REMOTE HANDLING EQUIPMENT; 420200* - Engineering- Facilities, Equipment, & Techniques

Citation Formats


                    Izaguirre, A, and Hashimoto, Minoru. A new computational structure for real-time dynamics.  United States: N. p., 1992. 
        Web.  doi:10.1177/027836499201100407.

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                    Izaguirre, A, & Hashimoto, Minoru. A new computational structure for real-time dynamics.  United States.  https://doi.org/10.1177/027836499201100407

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                    Izaguirre, A, and Hashimoto, Minoru. 1992.  
        "A new computational structure for real-time dynamics".  United States.  https://doi.org/10.1177/027836499201100407.

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@article{osti_6997668,

  title        = {A new computational structure for real-time dynamics},

  author       = {Izaguirre, A and Hashimoto, Minoru},

  abstractNote = {The authors present an efficient structure for the computation of robot dynamics in real time. The fundamental characteristic of this structure is the division of the computation into a high-priority synchronous task and low-priority background tasks, possibly sharing the resources of a conventional computing unit based on commercial microprocessors. The background tasks compute the inertial and gravitational coefficients as well as the forces due to the velocities of the joints. In each control sample period, the high-priority synchronous task computes the product of the inertial coefficients by the accelerations of the joints and performs the summation of the torques due to the velocities and gravitational forces. Kircanski et al. (1986) have shown that the bandwidth of the variation of joint angles and of their velocities is an order of magnitude less than the variation of joint accelerations. This result agrees with the experiments the authors have carried out using a PUMA 260 robot. Two main strategies contribute to reduce the computational burden associated with the evaluation of the dynamic equations. The first involves the use of efficient algorithms for the evaluation of the equations. The second is aimed at reducing the number of dynamic parameters by identifying beforehand the linear dependencies among these parameters, as well as carrying out a significance analysis of the parameters' contribution to the final joint torques. The actual code used to evaluate this dynamic model is entirely computer generated from experimental data, requiring no other manual intervention than performing a campaign of measurements.},

  doi          = {10.1177/027836499201100407},

  url          = {https://www.osti.gov/biblio/6997668},
  journal      = {International Journal of Robotics Research; (United States)},

  issn         = {0278-3649},

  number       = ,

  volume       = 11:4,

  place        = {United States},

  year         = {Sat Aug 01 00:00:00 EDT 1992},

  month        = {Sat Aug 01 00:00:00 EDT 1992}

}

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