The ornamental design for a motionsensor, as shown and described.
FIG. 1 is a front, right, top perspective view of a motion sensor;
FIG. 2 is a back, left, bottom perspective view thereof;
FIG. 3 is a front elevation view thereof;
FIG. 4 is a back elevation view thereof;
FIG. 5 is a left side view thereof;
FIG. 6 is a right side view thereof;
FIG. 7 is a top plan view thereof; and,
FIG. 8 is a bottom plan view thereof.
The dashed broken lines depict portions of the motion sensor that form no part of the claimed design. The dot-dashed broken lines represent boundaries of the claimed motion and form no part of the claimed design.