The invention relates to a device (80) and to a method for navigating and/or guiding the path of a vehicle (200), in particular of a wheelchair, and to a vehicle, in order to achieve increased safety and comfort during operation of the vehicle. The device (80) comprises at least one first sensor, in particular an inertial navigation unit (11), which is designed and arranged so as to detect at least one first body part, in particular an absolute position and/or position and/or rotation and/or translation, of a passenger of the vehicle (200) and to output first sensor signals (S1), and a second sensor, in particular an image-based sensor (21, 22), which is designed and arranged so as to detect at least the first body part of the passenger and/or its features and to output second sensor signals (S2). A control unit (100) receives the sensor signals (S1, S2), ascertains first control signals (ST1) based on the first sensor signals (S1), and it is ascertained, based on the second sensor signals (S2), whether the first control signals (ST1) comply with at least first reliability criteria. A safety mode is adopted when the first reliability criteria are not complied with.