In this paper we introduce a new passive multioutput lowfrequency vibration sensor that can measure acceleration and speed of the waves. Using the passive servo feedback control technique, the sensor shows the characteristics of a speed pendulum, which, however, is not the usual speed pendulum in largedamping state. A detailed mathematical analysis is carried out on the characteristics of the pendulum body. Simultaneous measurements of both acceleration and speed can be achieved using only one transducing mode. It is proved that the speed output is the output of the speed pendulum speedometer and the acceleration output is the output of the speed pendulum accelerometer. We also analyze the characteristics of the sensor, especially analyze the acceleration output characteristics in detail. Finally, the sensor was tested, and good frequencyresponse characteristics of acceleration output and speed output of the sensor in the frequency range from 0.1 Hz to 100 Hz were obtained, which satisfies the requirement of lowfrequency engineering vibration measurements, and the goal of using one sensor to measure both acceleration and speed at the same time is achieved.