Sliding mode control method with a feedforward compensation function

US5216342A · kind A · utility

Assignee

• FANUC CORPORATION · JP

Inventors

• Nobutoshi Torii · Hachioji, JP
• Ryo Nihei · Fujiyoshida, JP
• Tetsuaki Kato · Hadano, JP

Key dates

• Filing date: Jan 2, 1991
• Grant date: Jun 1, 1993
• Expiry date: Jan 2, 2011

Classification

• Technology area (CPC G): Physics
• CPC primary: G05B2219/42352
• WIPO field: Control
• WIPO sector: Instruments

Abstract

A sliding mode control method with a feedforward compensation function achieves a control response characteristic adapted to varying system parameters and properly maintains a manipulated variable affecting a controlled object. A position deviation (.epsilon.), speed deviation (.epsilon.), predicted maximum and minimum inertias (Jmax, J0), predicted maximum and minimum gravity loads (GRmax, GRmin), switching variable (s), integral element (.intg.(.epsilon.+C.multidot..epsilon.)), second differential (.theta.r) of the command position, and actual speed (.theta.) are periodically calculated on the basis of a command position (.theta.r), actual position (.theta.), inertia data, and gravity load data (100-102, 104, 107, 110, 114, 117, 120, 123, 127). Even when a nonlinear system parameter such as inertia varies, a proper torque command (T) is periodically calculated, as a manipulated variable, on the basis of a switching amount (T1) obtained by adding together five terms calculated in accordance with respective positive or negative signs of the switching variable, position deviation, integral element, second differential, and actual speed (105, 106, 108, 109, 111-113, 115, 116, 118, 11…