Contact-state obtaining apparatus and tire-deformation detecting apparatus

A contact-state obtaining apparatus for obtaining a contact state in which a tire of a wheel of a vehicle contacts a road surface, the apparatus comprising:

• a deformation detecting device which is supported by the wheel and which detects a deformation of the tire that is caused by a force exerted to the tire in a direction parallel to the road surface;
• and
• a contact-state obtaining portion which obtains, as said contact state, at least one of (a) a slipping state of the tire relative to the road surface and (b) the force exerted to the tire in a direction parallel to the road surface, based on the deformation of the tire detected by the deformation detecting device,
• wherein the deformation detecting device comprises a widthwise-direction-strain detecting portion which detects a strain of the tire in a widthwise direction thereof that is caused by the force exerted to the tire in a lateral direction thereof parallel to the road surface, and
• wherein the widthwise-direction-strain detecting portion comprises at least one sensor which detects a change of an actual length of a circumferentially continuous portion of the tire, the actual length being measured in a state of the tire in which the tire is not mounted on the wheel and does not support any weights of the vehicle, the change being caused by the force exerted to the tire in the lateral direction thereof parallel to the road surface.

A contact-state obtaining apparatus for obtaining a contact state in which a tire of a wheel of a vehicle contacts a road surface, the apparatus comprising:

• a deformation detecting device which is supported by the wheel and which detects a deformation of the tire that is caused by a force exerted to the tire in a direction parallel to the road surface;
• and
• a contact-state obtaining portion which obtains, as said contact state, at least one of (a) a slipping state of the tire relative to the road surface and (b) the force exerted to the tire in a direction parallel to the road surface, based on the deformation of the tire detected by the deformation detecting device,
• wherein the contact-state obtaining portion comprises:
• a ratio-related-amount obtaining portion which obtains a ratio-related amount that is related to a ratio of one of an adhering range in which the tire adheres to the road surface and a slipping range in which the tire slips on the road surface, to an other of the adhering range and the slipping range;
• and
• a ratio-related-amount-dependent contact-state obtaining portion which obtains, based on at least the ratio-related amount obtained by the ratio-related-amount obtaining portion, said at least one of (a) the slipping state of the tire and (b) the force exerted to the tire.

A contact-state obtaining apparatus for obtaining a contact state in which a tire of a wheel of a vehicle contacts a road surface, the apparatus comprising:

• a deformation detecting device which is supported by the wheel and which detects a deformation of the tire that is caused by a force exerted to the tire in a direction parallel to the road surface;
• and
• a contact-state obtaining portion which obtains, as said contact state, at least one of (a) a slipping state of the tire relative to the road surface and (b) the force exerted to the tire in a direction parallel to the road surface, based on the deformation of the tire detected by the deformation detecting device,
• wherein the deformation detecting device comprises an actual-length-change detecting portion which detects an amount of change of an actual length of a circumferentially continuous portion of the tire in a state of the tire in which the tire is not mounted on the wheel and does not support any weights of the vehicle, and
• wherein the contact-state obtaining portion comprises a friction-coefficient-dependent side-slip-angle obtaining portion which obtains a side slip angle of the wheel based on at least the amount of change of the actual length detected by the actual-length-change detecting portion and a friction coefficient with respect to the tire and the road surface.

A contact-state obtaining apparatus for obtaining a contact-state in which a tire of a wheel of a vehicle contacts a road surface, the apparatus comprising:

• a deformation detecting device which is supported by the wheel and which detects a deformation of the tire that is caused by a force exerted to the tire in a direction parallel to the road surface;
• and
• a contact-state obtaining portion which obtains, as said contact-state, a slipping state of the tire relative to the road surface, based on the deformation of the tire detected by the deformation detecting device,
• wherein the contact-state obtaining portion obtains, as the slipping state of the tire, a degree of slipping selected from the group consisting of an amount of slip, a slip ratio, and a side slip angle, and
• wherein the contact-state obtaining portion comprises a contact-length obtaining portion which obtains a contact length by which the tire contacts the road surface.

A contact-state obtaining apparatus for obtaining a contact state in which a tire of a wheel of a vehicle contacts a road surface, the apparatus comprising:

• a deformation detecting device which is supported by the wheel and which detects a deformation of the tire that is caused by a force exerted to the tire in a direction parallel to the road surface;
• and
• a contact-state obtaining portion which obtains, as said contact state, a slipping state of the tire relative to the road surface, based on the deformation of the tire detected by the deformation detecting device,
• wherein the deformation detecting device comprises a widthwise-direction-strain detecting portion which detects a strain of the tire in a widthwise direction thereof that is caused by the force exerted to the tire in a lateral direction thereof parallel to the road surface.