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Franklin, G. F.

Publications and source records attributed to Franklin, G. F..

11 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1991

Efficient control with an order (n) recursive inversion of the Jacobian for an n-link serial manipulator

A method is presented to order (n) recursively invert the Jacobian matrix for a serial n-link manipulator. By realizing that the Jacobian relationship involving accelerations is a special case for the forward dynamics problem, it is possible to obtain the Jacobian inverse by directly applying Rodriguez's (1987) recursive forward dynamics algorithm. In this technique, the n-link robot equation is formulated as a spatially recursive algorithm in the form of a filtering and smoothing problem. To compute the Jacobian inverse via this algorithm, the n-link manipulator is modeled with only a unit end-point mass and zero applied torques.

Meldrum, D. R.↗
NASA NTRS1988

Implementation of adaptive proximate time-optimal controllers

Following a review of the Proximate Time-Optimal Servomechanism (PTOS) and the adaptive version of PTOS (APTOS), implementation techniques are described which make both algorithms practical for discrete-time control of second-order plants with real roots. The double integrator plant and the real pole plus an integrator plant are both used as examples. The effects of unmodeled dynamics on the algorithms are discussed and illustrated by simulation and experiment.

Workman, M. L.↗
NASA NTRS1987

Adaptive proximate time-optimal servomechanisms - Continuous time case

A Proximate Time-Optimal Servo (PTOS) is developed, along with conditions for its stability. An algorithm is proposed for adapting the PTOS (APTOS) to improve performance in the face of uncertain plant parameters. Under ideal conditions APTOS is shown to be uniformly asymptotically stable. Simulation results demonstrate the predicted performance.

Workman, M. L.↗
NASA NTRS1987

Adaptive proximate time optimal servomechanisms: Discrete time case

Following a review of the continuous time proximate time-optimal servomechanism (PTOS), a discrete-time PTOS is developed, along with conditions for its stability. An algorithm is proposed for adapting PTOS when the plant parameters are not known yielding APTOS (adaptive PTOS). Under ideal conditions APTOs is shown to be uniformly asymptotically stable. Simulation results demonstrate the predicted performance, and experimental results validate the practically of APTOS.

Workman, M. L.↗
NASA NTRS1971

Guidance and control of flight vehicles

Progress reports on guidance and attitude control mechanisms of different flight vehicles are presented. The vehicles considered include orbiting spacecraft, supersonic aircraft, and general aviation aircraft. Data also cover orbital transfer using low thrust, automatic landing logic for aircraft, optimal and three dimensional turns for supersonic aircraft, and orbital rendezvous.

Breakwell, J. V.↗