The invention provides an auxiliary device for cooperating with a finger of a user's hand, which comprises a main body, a driving unit and a control unit.The main body comprises an opening, a fin body and a base.The fins form a plurality of accommodation spaces, and the openings are formed at least one of the fins and the base for a substance to be injected into or discharged from the accommodation spaces.The driving unit generates a first force to output the substance or a second force to extract the substance.The control unit is connected to the drive unit.The control unit generates a control signal to control the driving unit to generate a first force or a second force.The fins and the substrate present a first state when the substance is injected into the accommodation space, and a second state when the substance is discharged from the accommodation space.本創作提供一種輔具，供與一使用者的一手部之手指協同作動，其包含一主體、一驅動單元與一控制單元。主體包含一開口、一鰭片體與一基底。鰭片體形成複數容置空間，開口形成在鰭片體與基底之至少一者，以供一物質注入該等容置空間或該物質自該等容置空間排出。驅動單元產生第一作用力以輸出物質或產生第二作用力以抽取物質。控制單元連接驅動單元。控制單元產生一控制訊號，以控制驅動單元產生第一作用力或第二作用力。其中，當物質注入該等容置空間時，鰭片體與基底呈現一第一狀態，以及當物質自該等容置空間排出時，鰭片體與基底呈現一第二狀態。
