|An Impulse-time Perturbation Approach for a Symmetric Extrainsensitive Input Shaper
Chang-Wan Ha*, Dongwook Lee, Keun-Ho Rew, and Kyung-Soo Kim
International Journal of Control, Automation, and Systems, vol. 16, no. 3, pp.1239-1246, 2018
Abstract : "In this study, symmetric perturbation extra-insensitive input shapers (SPEI-ISs) are proposed to enhance
the robustness of the impulse-time perturbation approach, particularly toward the low-frequency range, with respect
to the modeled natural frequency. These perturbation-based extra-insensitive input shapers (PEI-ISs) provide a
wider range of robustness than the well-known robust input shapers, which include derivative input shapers (e.g.,
ZVD, ZVDD, and ZVDDD shapers) and extra-insensitive input shapers (EI-ISs). However, robustness may be lost,
particularly at lower frequencies, as a result of asymmetric placement of the notch points on the sensitivity curve.
To address this issue, an SPEI-IS is derived by placing the notch points symmetrically to enhance robustness,
particularly in the low-frequency range. In single-, two- and three-hump cases, explicit solutions are presented to
demonstrate the usability of the proposed shapers. The robustness and transient response are evaluated through
simulation and experiment and are compared to the response of conventional robust input shapers. It is concluded
that the proposed SPEI-IS improves robustness and transient response."
Motion control, input shaping technique, command shaping, robust input shaper, and transient response.