Road surface submergence estimation device

A road surface submergence estimation device comprising:

• a motion sensor configured to acquire an actual acceleration of a vehicle;
• a torque acquisition sensor configured to acquire an actual torque transmitted from a driving source to wheels of the vehicle, the driving source being mounted in the vehicle;
• and
• an estimation processor configured to determine whether a predetermined submergence determination condition is satisfied using the actual acceleration and the actual torque, and when it is determined that the submergence determination condition is satisfied, estimates that a road surface on which the vehicle is traveling is submerged,
• wherein the estimation processor is also configured to determine that the submergence determination condition is satisfied at least when a first condition that a first parameter is larger than a first threshold is satisfied, the first parameter being a parameter that becomes larger as a difference between a first variable and a second variable becomes larger, the first variable being a variable that becomes larger as the actual acceleration becomes larger, and the second variable being a variable that becomes larger as an actual torque becomes larger.