Abstract: A brake handle structure for a bicycle contains: at least one body, at least one rotatory arm, at least one brake lever, at least one angle signal sensor, and at least one power failure sensor. The at least one body includes a connection portion, an extension, and an engagement portion. The at least one rotatory arm includes a pulling segment, a coupling orifice, and a receiving orifice. The at least one brake lever includes a fixing segment connected with at least one electromagnetic clutch which includes a bolt attracted electromagnetically by the at least one electromagnetic clutch after conducting a power, and a defining orifice is defined adjacent to the at least one electromagnetic clutch. The at least one angle signal sensor is configured to sense and send a rotating angle of the rotatable column. The at least one power failure sensor has a movable sensing head.

Abstract: A method of operating an anti-lock braking system (ABS) of a bicycle comprising steps of: judging whether a power of a battery meets a set value; judging a moved angular position of a brake lever; outputting electric currents to operate the ABS; and judging whether a running speed of the bicycle is zero. When the power meets the set value, the ABS is turned on, and when the power of the battery is low, the ABS is not turned on. After the brake lever is pressed, the control unit judges whether the moved angular position of the brake lever reaches a set position. When the moved angular position does not reach the set position, the ABS is not turned on. When the moved angular angle reaches the set position, the ABS is turned on. The control unit outputs the electric currents to turn on the ABS, thus braking the bicycle.