A sensor mounting bracket includes: a first plate portion, a second plate portion, and a coupling element coupling the first and second plate portions. When X, Y, and Z axes perpendicular to each other are assumed, a second normal vector normal to a second mounting surface of the second plate portion has Y and Z components greater than 0 in a first state in which the first reference part is aligned with X direction and a first mounting surface of the first plate portion is in XZ plane, and a first normal vector normal to the first mounting surface has Y and Z components greater than 0 in a second state in which the second reference part is aligned with X direction and the second mounting surface is in XZ plane, the first normal vector being oriented differently from the second normal vector.
