Aiming　at　enhancing　the　vehicle　comfort　and　handling　performances,　this　article　concerns　with　the　development　of　the　vibration　control　method　for　the　semiactive　suspension　systems　installed　with　electrohydraulic　dampers.　To　reject　the　external　disturbances　induced　by　the　irregular　road　profile,　sliding　mode　was　intensively　investigated　for　vibration　control　owing　to　its　robust　feature　of　insensitivity　to　the　parametric　uncertainty　and　external　disturbances.　However,　the　unknown　nonlinearity　of　damper　behaviors　leads　to　model　mismatch　to　cause　the　high-frequency　switching　of　sliding-mode　controllers.　Consequently,　the　severe　chattering　phenomenon　produces.　Although　saturated　function　is　available　to　alleviate　the　chattering　problem　of　sliding-mode　control,　there　is　always　a　tradeoff　problem　between　tracking　accuracy　and　chattering　suppression.　To　solve　this　problem,　this　study　provides　a　new　intelligent　robust　control　method　for　simultaneous　improvements　of　tracking　accuracy　and　chattering　suppression.　Given　the　computational　efficiency,　an　improved　extreme　learning　machine　(ELM)　is　proposed　to　intelligently　approximate　and　compensate　the　unmodeled　dynamics　with　unknown　nonlinearity　to　restrain　the　chattering　problem,　where　a　new　adaptive　learning　law　is　designed　in　the　premise　of　Lyapunov　stability.　To　validate　the　effectiveness　and　efficiency　of　the　proposed　ELM-based　robust　control,　a　quarter-car　test　rig　was　set　up　for　the　hardware-in-the-loop　test.　Experimental　results　show　that　the　proposed　controller　outperforms　the　sliding-mode　controller　with　saturated　function　in　depressing　the　sprung　mass　acceleration　and　tire　deflection,　showing　its　significance　in　both　control　performance　enhancement　and　chattering　elimination.　©　1996-2012　IEEE.