Actuators are pivotal for empowering robots to execute a wide array of tasks and adapt to diverse surroundings. However, conventional actuators with low switching frequency and prolonged response time significantly comprise the adaptability of robots, restricting them to single operation condition. This paper presents a solution to this issue by introducing a magnetorheological (MR) actuator with real-time controllable damping. Compared to conventional actuators, the MR actuator boasts exceptional dexterity, featuring a significantly elevated switching frequency and swifter response time. To validate the MR actuator's remarkable dexterity, rapid commutation tests and transient response experiments were conducted. Impressively, the MR actuator achieved a stable switching frequency up to 10 Hz, surpassing that of conventional actuators (2 Hz). Moreover, it demonstrated reduced response time and heightened energy efficiency. Beyond robotics, MR actuators also find applications in areas which require improved machinery precision and production efficiency.