Travel control device

A travel control device of a forklift including

• a vehicle,
• a drive wheel that is provided on the vehicle and that configured to drive the vehicle,
• a straddle leg that is provided on the vehicle and is configured to travel together with the vehicle, and
• a cargo handling device that is provided on the straddle leg and is driven such that a fork is configured to ascend and descend in a vertical direction and configured to move forward and backward in a traveling direction of the vehicle, the travel control device comprising:
• a center-of-gravity position detection unit configured to detect a center-of-gravity position of the forklift including a cargo when the cargo is placed on the fork;
• a correspondence relationship information acquisition unit configured to acquire correspondence relationship information in which a lifting height indicating a position of the fork in the vertical direction, a reach length indicating a protrusion amount of the fork in the traveling direction, and an acceleration for positioning a zero moment point in a stable region are associated with each other, based on the center-of-gravity position;
• a cargo handling device information acquisition unit configured to acquire the lifting height and the reach length of the fork;
• an allowable acceleration acquisition unit configured to acquire an allowable acceleration from the correspondence relationship information based on the lifting height and the reach length acquired by the cargo handling device information acquisition unit;
• a target reach length acquisition unit configured to acquire a target reach length from the correspondence relationship information based on the lifting height and a maximum acceleration when the allowable acceleration is less than the maximum acceleration of the forklift;
• a cargo handling device drive unit configured to drive the cargo handling device such that the reach length of the fork is the target reach length;
• and
• a drive wheel control unit configured to drive the drive wheel such that the forklift is accelerated at an acceleration greater than the allowable acceleration when the reach length of the fork is the target reach length.