Low-speed antiskid control for multigain hydraulic valve brake system

摘要

A low-speed antiskid control for a multigain hydraulic valve brake system for an airplane is disclosed. The antiskid control includes low- and high-pressure bias modulation (PBM) high step thresholds. At high speeds the low PBM threshold is used to control a PBM high step firing. At low speeds, the high PBM threshold is used to prevent a PBM high step firing unless a deep skid is occurring. The use of a high threshold at low airplane speeds prevents a low speed control loss due to PBM high step firing reducing brake pressure to below minimum brake contact pressure. <IMAGE>