Vehicle notification device and vehicle notification method
To make a notification to the driver so that the driver can distinguish or recognize the notification. A vehicle notification device ( 1 a ) inputs a first sweep signal whose frequency is changed in a predetermined frequency range, to a vibrator ( 4 ), calculates frequency characteristics of a vibration in the vehicle interior, detects a frequency range in which the signal level of vehicle-travel-time frequency characteristics is higher than the signal level of vehicle-stop-time frequency characteristics by a predetermined level amount or more, generates a second sweep signal whose frequency is changed in a range obtained by excluding the detected frequency range from the predetermined frequency range of the first sweep signal, and outputs the second sweep signal from the vibrator ( 4 ).
1. A vehicle notification device comprising:
a vibrator disposed in a seat in a vehicle interior;
a first signal generator configured to generate a first sweep signal by changing a frequency in a predetermined frequency range;
a measurement unit configured to measure a vibration in the vehicle interior;
a frequency analyzer configured to calculate vehicle-stop-time frequency characteristics and vehicle-travel-time frequency characteristics by measuring a vibration using the measurement unit in the vehicle interior during a vehicle stop and during vehicle travel while inputting the first sweep signal to the vibrator and to detect a frequency range in which a signal level of the vehicle-travel-time frequency characteristics is higher than a signal level of the vehicle-stop-time frequency characteristics by a predetermined level amount or more; and
a second signal generator configured to generate a second sweep signal by changing a frequency in a new frequency range obtained by excluding the frequency range detected by the frequency analyzer from the predetermined frequency range in which the frequency of the first sweep signal is changed, wherein
the vibrator generates a notification vibration on the basis of the second sweep signal generated by the second signal generator.
2. The vehicle notification device according to claim 1 , further comprising a correction processor configured to correct the second sweep signal so that an amplitude value of the second sweep signal varies with time, by multiplying the second sweep signal by a correction signal whose amplitude value varies with time, wherein
the vibrator generates the notification vibration on the basis of the second sweep signal corrected by the correction processor.
3. The vehicle notification device according to claim 2 , wherein amplitude characteristics of the correction signal are set on the basis of amplitude characteristics of a vibration that occurs in a vehicle when the vehicle passes over rumble strips.
4. A vehicle notification method performed by a vehicle notification device that generates a notification vibration using a vibrator disposed in a seat in a vehicle interior, the method comprising:
a first signal generation step of generating, by a first signal generator, a first sweep signal by changing a frequency in a predetermined frequency range;
a measurement step of measuring, by a measurement unit, a vibration in the vehicle interior;
a frequency analysis step of calculating, by a frequency analyzer, vehicle-stop-time frequency characteristics and vehicle-travel-time frequency characteristics by measuring a vibration using the measurement unit in the vehicle interior during a vehicle stop and during vehicle travel while inputting the first sweep signal to the vibrator and detecting a frequency range in which a signal level of the vehicle-travel-time frequency characteristics is higher than a signal level of the vehicle-stop-time frequency characteristics by a predetermined level amount or more;
a second signal generation step of generating, by a second signal generator, a second sweep signal by changing a frequency in a new frequency range obtained by excluding the frequency range detected in the frequency analysis step from the predetermined frequency range in which the frequency of the first sweep signal is changed; and
a notification vibration generation step of generating, by the vibrator, the notification vibration on the basis of the second sweep signal generated in the second signal generation step.
5. The vehicle notification method according to claim 4 , wherein the notification vibration generation step comprises if the frequency analyzer does not detect the frequency range in which the signal level of the vehicle-travel-time frequency characteristics is higher than the signal level of the vehicle-stop-time frequency characteristics by the predetermined level amount or more in the frequency analysis step, generating, by the vibrator, the notification vibration using the first sweep signal as the second sweep signal.
6. The vehicle notification method according to claim 4 , further comprising a correction step of correcting, by a correction processor, the second sweep signal so that an amplitude value of the second sweep signal varies with time, by multiplying the second sweep signal by a correction signal whose amplitude value varies with time, wherein
the notification vibration generation step comprises generating, by the vibrator, the notification vibration on the basis of the second sweep signal corrected in the correction step.
7. The vehicle notification method according to claim 6 , wherein amplitude characteristics of the correction signal used in the correction step are set on the basis of amplitude characteristics of a vibration that occurs in a vehicle when the vehicle passes over rumble strips.