System for sensing hands-on or off of steering wheel and method thereof

A system for detecting hands-on or off of a steering wheel, the system comprising:

• a first sensor detecting a direct hands-on sense value depending on a grip area of the steering wheel;
• a second sensor detecting an indirect hands-on sense value depending on a magnitude of a torque for rotating the steering wheel;
• and
• a controller connected to the first sensor and the second sensor and combining the direct hands-on sense value detected by the first sensor and the indirect hands-on sense value detected by the second sensor to each other to determine a grip state of the steering wheel depending on a combined hands-on sense condition, and then to display and warn a result of determining the grip state of the steering wheel through an output unit,
• wherein the controller is configured to set a plurality of direct hands-on sense regions and a direct hands-off sense region separately from each other depending on a magnitude of the direct hands-on sense value,
• wherein the controller is configured to set a plurality of indirect hands-on sense regions and an indirect hands-off sense region separately from each other depending on a magnitude of the indirect hands-on sense value,
• wherein the controller is configured to detect hands-on sense regions including the direct and indirect hands-on sense values separately from each other when the direct and indirect hands-on sense values are input into the hands-on sense regions,
• wherein the controller is configured to determine the grip state of the steering wheel from the hands-on sense condition in which the detected hands-on sense regions are combined to each other, and
• wherein the controller is configured to output a signal indicating the grip state of the steering wheel,
• wherein the direct hands-on sense region is subdivided into a direct hands on sense-strong region, a direct hands on sense-middle region, a direct hands on sense-weak region and a direct hands-off sense region depending on the magnitude of the direct hands-on sense value,
• wherein the indirect hands-on sense region is subdivided into an indirect hands on sense-strong region, an indirect hands on sense-middle region, an indirect hands on sense-weak region and an indirect hands-off sense region depending on the magnitude of the indirect hands-on sense value,
• wherein a hands-off switch counter generates and accumulates a number when the measured direct hands-on sense value is included in the direct hands on-weak region and the measured indirect hands-on sense value is included in the indirect hands-on sense region,
• wherein a current grip state of the steering wheel is detected and then be displayed and warned to a driver depending on the accumulated number of the hands-off switch counter, and
• wherein the hands-off switch counter is provided to determine the hands-on state and the hands-off state based on whether the accumulated number is greater than a reference number.