Information transmission device

Abstract

The invention provides an information transmission device which can improve the predictability of an occupant for a behavior caused by acceleration and deceleration of a vehicle. An information transmission device (100) provided in a vehicle having a drive device for driving wheels and a brake device for braking the wheels is configured to comprise: a parameter detection unit (30a) for detecting a parameter relating to at least one of the driving force of the drive device and the braking force of the brake device; an excitation waveform generation unit (110) that generates an excitation waveform; an excitation unit (170) that excites the air around the occupant using the excitation waveform; and a gain adjustment unit (130) that increases the output gain of the excitation waveform in response to an increase in the absolute value of the differential value of the parameter.

Description

Technical Field

[0001] The present invention relates to an information transmitting device for transmitting information related to the behavior of a vehicle to an occupant of a vehicle. Background Art

[0002] In vehicles such as automobiles, as a technology related to outputting sound to passengers according to the state of the vehicle, for example, Patent Document 1 describes a method of presenting the steering amount of a steering wheel using sound that changes in conjunction with the steering amount in order to provide a driving assistance device that can easily identify a steering angle and a steering direction.

[0003] Specifically, it is recorded that the sound level becomes higher as the steering amount increases, or the intensity, pitch, timbre, sound pressure, frequency, position of the sound image, etc. of the sound are changed to present the steering amount of the steering wheel.

[0004] Patent document 2 describes a vehicle music generating device that simply generates music that reflects the behavior of a vehicle and the operation of a driver. The vehicle music generating device comprises: a storage unit that stores a plurality of sound source cycle patterns corresponding to respective information based on the operation of the driver of the vehicle or the behavior of the vehicle; and a control unit that selects a specific sound source cycle pattern from the plurality of sound source cycle patterns based on respective information and controls the output or stop of the output.

[0005] Prior art literature Patent Literature Patent Document 1: Japanese Patent Application Publication No. 2007-62706 Patent Document 2: Japanese Patent Application Publication No. 2016-66912 Summary of the invention

[0006] Technical issues Since there is a time response delay from the acceleration or braking operation of the vehicle (hereinafter collectively referred to as acceleration and deceleration operations) to the actual behavior of the vehicle body causing longitudinal acceleration, pitch angle, etc., depending on the conditions of the steering action, the occupants may sometimes feel discomfort and uneasiness due to the sudden generation of longitudinal acceleration, etc., and thus being unable to properly maintain their bodies.

[0007] In response to this, for example, measures such as reducing the responsiveness of the vehicle to acceleration and deceleration operations or improving the holding performance of the occupant on the seat or the like are considered.

[0008] However, if the responsiveness to acceleration and deceleration operations is reduced, the behavior of the vehicle becomes slow, which results in a loss of performance and marketability of the vehicle. In addition, it is difficult to appropriately respond to occupants of various body types with seat measures.

[0009] In view of the above-mentioned problems, an object of the present invention is to provide an information transmission device that improves the predictability of the behavior of the vehicle due to acceleration and deceleration by the occupant.

[0010] Technical Solution In order to solve the above-mentioned problems, an information transmission device of one embodiment of the present invention is characterized in that it is arranged in a vehicle, the vehicle has a driving device for driving wheels, and a braking device for braking the wheels, and the information transmission device comprises: a parameter detection unit, which detects a parameter related to at least one of the driving force of the driving device and the braking force of the braking device; an excitation waveform generating unit, which generates an excitation waveform; an excitation unit, which uses the excitation waveform to vibrate the air around the occupant; and a gain adjustment unit, which increases the output gain of the excitation waveform in response to an increase in the absolute value of the differential value of the parameter.

[0011] Thus, by generating a sound whose sound pressure increases with the increase in the absolute value of the differential value of a parameter related to at least one of the driving force of the driving device and the braking force of the braking device, it is possible to use the sound to make the occupants foresee the occurrence of behavior at the initial stage of vehicle acceleration or deceleration, before the vehicle actually generates longitudinal acceleration, pitch angle, etc.

[0012] This improves the predictability of the vehicle behavior by the occupants, and prevents the occupants from feeling a sense of abruptness regarding the vehicle behavior.

[0013] In the present invention, the excitation waveform may have a main frequency within a frequency band of 100 to 400 Hz.

[0014] This makes it possible to use Pacinian corpuscles or the like that are highly sensitive in the audible range and highly sensitive in terms of skin sensation, thereby improving the passenger's perception of sound and recognition of sound by skin sensation. Therefore, information can be more reliably transmitted to the passenger.

[0015] Here, it is more preferable to set the main frequency in the frequency band of 150 to 300 Hz so that a region where the receptor has better sensitivity can be used, thereby promoting the above-mentioned effect.

[0016] In the present invention, the increase rate of the output gain in the gain adjustment unit with respect to an increase in the absolute value of the differential value is maximum in a region where the absolute value of the differential value is small, and decreases as the absolute value of the differential value increases.

[0017] Thus, a large output gain can be set even in a region where the absolute value of the differential value is relatively small, and information can be appropriately transmitted to the occupant even in the early stage of acceleration or deceleration when the change in the driving force or the braking force is small.

[0018] For example, the output gain can be set based on a logarithmic function of the absolute value of the differential value.

[0019] In the present invention, the gain adjustment unit may set the output gain so that the sound pressure generated by the excitation of the excitation unit does not stand out at the ear of at least one occupant relative to background noise when the vehicle is traveling.

[0020] Thus, since the sound generated by the excitation of the excitation unit is buried in the background noise of the vehicle, it is possible to prevent the sound from being irritating to the passengers and to appropriately convey information.

[0021] In the present invention, the vehicle can be configured to include an input device, which performs an acceleration operation by a pedaling action starting from a predetermined position of a single pedal, and also performs a braking action by a return action starting from the predetermined position, and the gain adjustment unit makes the output gain set according to the return action larger than the output gain set according to the pedaling operation.

[0022] Thus, by increasing the output gain on the return operation side of the pedal where the driver is less likely to feel the reaction force, the vehicle body behavior accompanying deceleration can be appropriately anticipated.

[0023] Technical Effects As described above, according to the present invention, it is possible to provide an information transmission device that improves the predictability of the occupant's behavior caused by the acceleration and deceleration of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a diagram schematically showing a system configuration of a vehicle having a first embodiment to which the information transmission device of the present invention is applied.

[0025] Figure 2 It is a schematic diagram showing the structure of the pedal part in the first embodiment.

[0026] Figure 3 It is a diagram schematically showing the system configuration of the information transmission device according to the first embodiment.

[0027] Figure 4 It is a diagram schematically showing an example of an excitation waveform in the first embodiment.

[0028] Figure 5 It is a diagram schematically showing the timing of electrical pulses emitted by a receptor when stimulated.

[0029] Figure 6 is a graph showing the distribution of the sensitivity of Pacinian corpuscles and Meissner corpuscles with respect to frequency.

[0030] Figure 7 This is a diagram schematically showing an example of gain adjustment in the first gain adjustment unit according to the first embodiment.

[0031] Figure 8 This is a diagram schematically showing an example of the output history of the microphone in the first embodiment.

[0032] Fig. 9 This is a diagram showing an example of the correlation between the sound pressure and frequency of the background noise in the first embodiment.

[0033] Fig.10 This is a diagram schematically showing an example of gain adjustment in the second gain adjustment unit according to the first embodiment.

[0034] Fig.11 It is a diagram schematically showing the arrangement in the cabin of a vehicle in which the information transmission device according to the first embodiment is installed.

[0035] Explanation of symbols 1: Vehicle 10: Brake control unit 11: Vehicle speed sensor 12: Acceleration sensor 13: Brake pedal sensor 14: Reaction force generating device 15: Master cylinder 20: Hydraulic control unit 21: Wheel cylinder 30: Motor generator control unit 30a: Accelerator pedal sensor 31: Electric generator 40: Accelerator pedal 41: Bracket 42: Rod 43: Treading part 100: Information transmission device 110: Waveform generation unit 120: Differential calculation unit 130: First gain adjustment unit 140: Microphone 150: Sensing value calculation unit 160: Second gain adjustment unit 170 (170FR, 170FL, 170RR, 170RL): Speakers 200: Carriage 210: Driver's seat 220: Passenger seat 230: Backseat 240: Dashboard DETAILED DESCRIPTION

[0036] <First Embodiment> Hereinafter, a first embodiment of an information transmission device to which the present invention is applied will be described.

[0037] The information transmission device of the first embodiment is provided in an automobile (vehicle) such as a passenger car, for example, and transmits information on the behavior associated with acceleration and deceleration of the vehicle to passengers such as a driver and a fellow passenger.

[0038] In the first embodiment, the vehicle includes a pedal-type operating device that allows a driver to perform an acceleration operation (accelerator operation) and a slow braking operation by regenerative braking by operating a single pedal.

[0039] As an example, the vehicle is an electric vehicle such as a battery electric vehicle (BEV), a motor-electric hybrid vehicle (HEV), or a fuel cell vehicle (FCV) that uses a motor generator such as a permanent magnet synchronous motor, a coil-excited synchronous motor, or an induction motor as a driving power source.

[0040] Figure 1 It is a diagram schematically showing a system configuration of a vehicle including the information transmission device according to the first embodiment.

[0041] Figure 2 It is a schematic diagram showing the structure of the pedal part in the first embodiment.

[0042] The vehicle 1 includes a brake control unit 10, a hydraulic control unit 20, a motor generator control unit 30, and an accelerator pedal 40 (see Figure 2 ), information transmission device 100, etc.

[0043] Each of these units includes a microcomputer having an information processing unit such as a CPU, a storage unit such as a RAM and a ROM, an input / output interface, and a bus that connects them.

[0044] In addition, the units can communicate with each other via an in-vehicle LAN connection such as a CAN communication system or a direct connection.

[0045] The brake control unit 10 performs coordinated control of hydraulic friction braking and regenerative braking in accordance with an operation of a brake pedal (not shown).

[0046] In addition, the brake control unit 10 has a function of performing anti-lock brake control and behavior stabilization control.

[0047] The anti-lock brake control is a control that periodically reduces the braking force of a wheel when wheel lock, in which the rotation of the wheel stops, is detected during braking.

[0048] The behavior stabilization control is a control for generating a yaw moment in a restoring direction by using the braking force difference between the left and right wheels when an understeering behavior or an oversteering behavior occurs.

[0049] The brake control unit 10 is connected to a vehicle speed sensor 11 , an acceleration sensor 12 , a brake pedal sensor 13 , and a reaction force generating device 14 .

[0050] Furthermore, the brake device of the vehicle 1 further includes a master cylinder 15 .

[0051] The vehicle speed sensor 11 is provided on a hub bearing housing (not shown) that rotatably supports the wheels, and generates a vehicle speed signal corresponding to the rotational angular velocity of each wheel.

[0052] The brake control unit 10 calculates the running speed (vehicle speed) of the vehicle 1 based on the output of the vehicle speed sensor 11 .

[0053] The acceleration sensor 12 is provided in a so-called unsprung portion of a suspension device (not shown) that supports a wheel so as to be able to generate a stroke relative to a vehicle body.

[0054] The acceleration sensor 12 detects the vertical acceleration of a member provided under the spring, such as a suspension arm or a hub bearing housing.

[0055] The acceleration sensor 12 is a vibration input detection unit that detects vibration input from a road surface.

[0056] Furthermore, the brake control unit 10 is provided with a vehicle body longitudinal acceleration sensor, a vehicle body lateral acceleration sensor, a yaw rate sensor, and the like (not shown) for the above-mentioned behavior stabilization control and the like.

[0057] The brake pedal sensor 13 includes an encoder that detects the operation amount (depression amount) of the brake pedal.

[0058] The reaction force generating device 14 generates a reaction force in a direction to return the brake pedal to an initial position (a position not depressed) according to a command from the brake control unit 10 .

[0059] The reaction force generating device 14 generates a reaction force when regenerative braking is used, for example, using a driving power source such as an electric actuator.

[0060] The master cylinder 15 pressurizes brake fluid, which is a working fluid for friction braking, in response to a stepping operation of a tread portion of a brake pedal.

[0061] The brake fluid pressure generated by the master cylinder 15 is transmitted to the hydraulic control unit 20 via piping.

[0062] The hydraulic control unit (HCU) 20 is a hydraulic control device having a function of individually adjusting the brake fluid pressure of the wheel cylinder 21 of each wheel.

[0063] The hydraulic control unit 20 includes an electric pump for pressurizing the brake fluid, and a pressure-increasing valve, a pressure-reducing valve, a pressure-maintaining valve, and the like for controlling the brake fluid pressure of each wheel cylinder.

[0064] The hydraulic control unit 20 is connected to the master cylinder 15 , the wheel cylinder 21 , and the like via brake fluid pipes.

[0065] The brake fluid pressure generated by the master cylinder 15 is transmitted to the wheel cylinders 21 via the hydraulic control unit 20 .

[0066] The hydraulic pressure control unit 20 has a function of overriding the brake fluid pressure generated by the master cylinder 15 to increase or decrease the brake fluid pressure of each wheel cylinder.

[0067] The wheel cylinder 21 is provided at each wheel, and presses a brake pad against a disc rotor, for example, to generate a friction force (braking force) corresponding to the brake fluid pressure.

[0068] In addition, in the regenerative coordination control of the brake control unit 10, when the control share ratio of regenerative braking (brake device) is generated or the control share ratio of regenerative braking (brake device) is increased, the hydraulic control unit 20 has the function of reducing or cutting off the hydraulic pressure of the brake fluid transmitted from the master cylinder 15.

[0069] In this case, the brake control unit 10 generates a reaction force of the brake pedal using the reaction force generating device 14 in order to give the driver a feeling simulating the use of the hydraulic friction brake.

[0070] The brake control unit 10 has a function of performing slow braking (for example, a deceleration of about 0.1 to 0.3 G) by regenerative braking in response to the return movement of the accelerator pedal 40 from a predetermined position.

[0071] The motor generator control unit 30 centrally controls the motor generator 31 and its auxiliary machines.

[0072] The motor generator 31 is a rotating electric machine used as a power source (drive device) for traveling of the vehicle 1 .

[0073] The motor generator control unit 30 includes an inverter and the like for supplying electric power supplied from a power source such as a battery for traveling to the motor generator 31 .

[0074] The motor generator 31 can be mounted on the vehicle body (sprung portion) and can transmit driving force to the wheels via a differential (differential mechanism), a drive shaft, etc., but is not limited thereto and may be, for example, an in-wheel motor.

[0075] The motor generator control unit 30 switches between a drive mode in which the motor generator 31 generates output torque (driving force) and a regenerative power generation mode in which the motor generator 31 generates regenerative power and absorbs torque transmitted from the wheels to generate braking force.

[0076] In the driving mode, the motor generator control unit 30 performs control so that the actual torque actually generated by the motor generator 31 matches the requested torque set based on the operation amount of the accelerator pedal 40 and the like.

[0077] In the regenerative power generation mode, the motor generator control unit 30 controls the absorption torque in the motor generator 31 according to the requested braking force instructed from the brake control unit 10 .

[0078] Figure 2 The illustrated accelerator pedal 40 is a foot-operated operation unit for the driver to perform acceleration and braking operations.

[0079] The accelerator pedal 40 includes a bracket 41 , a rod portion 42 , a tread portion 43 , and the like.

[0080] The bracket 41 is a base portion that supports the rod portion 42 so as to be rotatable about a rotation axis along the vehicle width direction.

[0081] The bracket 41 includes a spring (not shown) that urges the rod portion 42 in the return direction (initial position side).

[0082] The bracket 41 is attached to a footrest T provided as a partition wall at the front portion of the vehicle compartment.

[0083] The rod portion 42 is a member that protrudes downward and obliquely rearward from the bracket 41 .

[0084] The tread portion 43 is a portion provided at a protruding end portion (an end portion on the side opposite to the bracket 41 side) of the rod portion 42 and abuts against the bottom surface of the passenger's foot.

[0085] like Figure 2 As shown, the tread portion 43 is capable of swinging in the front-rear direction around a fulcrum (pivot) of the rod portion 42 on the bracket 41 side.

[0086] A neutral position P1 is set between an initial position P0 where the tread portion 43 is not pressed by the passenger's foot and a fully open position P2 where the tread portion 43 is stepped on by the passenger's foot until the tread portion 43 contacts the stopper.

[0087] The accelerator pedal 40 uses a range from the neutral position P1 to the fully open position P2 for acceleration operation, and uses a range from the neutral position P1 to the initial position P0 for braking operation.

[0088] The braking force (deceleration G) obtained by the regenerative braking increases in accordance with the displacement amount (return amount) from the neutral position P1 to the initial position P0 side.

[0089] The motor generator control unit 30 is connected to an accelerator pedal sensor 30 a .

[0090] The accelerator pedal sensor 30 a includes an encoder that detects the rotational angle position of the rod portion 42 of the accelerator pedal 40 .

[0091] The accelerator pedal sensor 30 a is provided on the bracket 41 .

[0092] The motor generator control unit 30 detects the stroke S from the initial position of the tread portion 43 based on the output of the accelerator pedal sensor 30 a .

[0093] In order to control the regenerative braking, the stroke S detected by the accelerator pedal sensor 30 a is also transmitted to the brake control unit 10 .

[0094] The accelerator pedal sensor 30a functions as a parameter detection unit of the present invention.

[0095] The information transmission device 100 vibrates the air around the ears of the occupant through the speaker 170 disposed in the vehicle cabin, and notifies the occupant of a precursor to the occurrence of a vehicle behavior through an acoustic signal.

[0096] Figure 3 It is a diagram schematically showing the system configuration of the information transmission device according to the first embodiment.

[0097] The information transmission device 100 includes a waveform generation unit 110 , a differential operation unit 120 , a first gain adjustment unit 130 , a microphone 140 , a sensing value operation unit 150 , a second gain adjustment unit 160 , a speaker 170 , and the like.

[0098] The waveform generation unit 110 generates an excitation waveform which is a waveform of an acoustic signal generated by the speaker 170 .

[0099] Figure 4 It is a diagram schematically showing an example of an excitation waveform in the first embodiment.

[0100] exist Figure 4 In the figure, the horizontal axis represents time and the vertical axis represents voltage (amplitude).

[0101] For example Figure 4As shown in (a) of FIG. 8 , the excitation waveform can be set to a sine wave.

[0102] In addition, for example Figure 4 As shown in (b) of FIG. 8 , the excitation waveform can be a waveform obtained by superimposing (combining) a plurality of sinusoidal waves having different wavelengths.

[0103] In addition, the excitation waveform is not limited to these waveforms, and can be changed as appropriate.

[0104] For example, various waveforms such as rectangular waves, triangular waves, and waveforms simulating the sound of a vehicle running can be used alone as the excitation waveform, or various waveforms such as rectangular waves, triangular waves, and waveforms simulating the sound of a vehicle running can be combined with other waveforms for use.

[0105] In the first embodiment, the frequency of the excitation waveform can be set to, for example, 100 to 400 Hz, and more preferably, can be set to have a main frequency in the range of 150 to 300 Hz.

[0106] The reasons are described below.

[0107] As sensory receptors that sense vibrations when the air around the occupant is excited, there are Merkel cells, Meissner corpuscles, Pacinian corpuscles, and the like.

[0108] Figure 5 It is a diagram schematically showing the timing of electrical pulses emitted by a receptor when stimulated.

[0109] exist Figure 5 In the figure, the horizontal axis represents time, and the vertical axis represents pressure, and the electrical pulse generation states of Merkel cells, Meissner corpuscles, and Pacinian corpuscles, in order from the top.

[0110] The response of Merkel cells is relatively slow, corresponding to the DC component.

[0111] Meissner corpuscles correspond to the moment when the rate of change (velocity) of contact pressure is generated.

[0112] Pacinian corpuscles correspond to the instant of transient change and are the most sensitive of these receptors.

[0113] As a receptor through which passengers sense tiny vibrations as a combination of auditory and tactile information, Pacinian corpuscles are believed to have the highest sensitivity.

[0114] Figure 6 is a graph showing the distribution of the sensitivity of Pacinian corpuscles and Meissner corpuscles with respect to frequency.

[0115] exist Figure 6 In FIG. 1 , the horizontal axis represents the frequency and the vertical axis represents the amplitude at the threshold value, and it is shown that the smaller the value, the better the sensitivity.

[0116] like Figure 6 As shown, the Pacinian corpuscles exhibit good sensitivity in the region around 100 to 400 Hz, and particularly exhibit better sensitivity in the region around 150 to 300 Hz.

[0117] Such an area is included in the range of 20 Hz to 20 kHz which is generally set as the audible range of humans.

[0118] As an example, the main frequency of the excitation waveform can be set to 250 Hz.

[0119] The differential calculation unit 120 obtains information on the stroke S of the accelerator pedal 40 detected by the accelerator pedal sensor 30 a from the motor generator control unit 30 , and calculates a time-differentiated differential value ΔS.

[0120] The differential calculation unit 120 sequentially transmits the calculated differential values ​​ΔS to the first gain adjustment unit 130 .

[0121] The first gain adjustment unit 130 performs a first gain adjustment, which will be described below, on the fundamental wave of the excitation waveform generated by the waveform generation unit 110 .

[0122] The first gain adjustment is an adjustment for changing the gain G1 which is an output gain multiplied by the voltage of the excitation waveform according to the differential value ΔS (rate of change per unit time) of the stroke S (a parameter related to at least one of the driving force and the braking force) of the accelerator pedal 40 .

[0123] Figure 7 FIG. 1 is a diagram schematically showing an example of gain adjustment in the first gain adjustment unit.

[0124] exist Figure 7 In FIG. 1 , the horizontal axis represents the differential value ΔS of the stroke S of the accelerator pedal 40 , and the vertical axis represents the gain G1 multiplied by the voltage of the excitation waveform.

[0125] The gain G1 can be configured to increase in response to an increase in the absolute value of the differential value ΔS.

[0126] The increase rate of the gain G1 in the first gain adjustment unit 130 with respect to the increase in the absolute value of the differential value ΔS can be configured to be maximum in a region where the absolute value of the differential value ΔS is small and to decrease in response to the increase in the absolute value of the differential value ΔS.

[0127] When the depressed side and the return side of the accelerator pedal 40 are compared, if the absolute value of the differential value ΔS is equal, the gain G1 of the return side (deceleration operation) is set larger than the gain G1 of the depressed side (acceleration operation).

[0128] The determination between the depressed side and the return side of the accelerator pedal 40 can be made based on the sign of the differential value ΔS.

[0129] For example, the gain G1 in the first gain adjustment unit 130 can be calculated from the absolute value of the differential value ΔS of the stroke S using a logarithmic function.

[0130] The gain G1 is expressed by the following equation 1, for example.

[0131] Gain G1 = log (absolute value of stroke differential value ΔS × coefficient k) (Formula 1) The coefficient k can be set to a value that is set in, for example, the vehicle development stage in accordance with the vehicle characteristics (eg, the driving force and braking force characteristics with respect to changes in the stroke S, the center of gravity position, etc.).

[0132] The microphone 140 is a sound collecting device that is disposed in the vehicle compartment and collects background noise in the vehicle compartment.

[0133] Microphone 140 is preferably disposed at a position close to the ear of the occupant, and can be configured to be provided on a headrest portion of a seat, for example.

[0134] The output of the microphone 140 is transmitted to the sensing value calculation unit 150 .

[0135] The sensing value calculation unit 150 extracts a component of a predetermined frequency band from the background noise of the vehicle acquired by the microphone 140 , and transmits the sound pressure of the extracted component to the second gain adjustment unit 160 as a sensing value.

[0136] Figure 8 This is a diagram schematically showing an example of the output history of a microphone.

[0137] exist Figure 8 In FIG. 1 , the horizontal axis represents time, and the vertical axis represents the sound pressure of the background noise acquired by the microphone 140 .

[0138] The sensing value calculation unit 150 performs a fast Fourier transform (FFT) process on the sound signal of the background noise acquired by the microphone 140 to convert the sound signal into a frequency domain, and further performs a bandpass filter process to extract a component of a predetermined frequency band.

[0139] The extracted frequency band is set to include the main frequency of the excitation waveform output by the waveform generation unit 110 .

[0140] The sensing value calculation unit 150 sets the average sound pressure of the extracted frequency band as the sensing value used in the second gain adjustment.

[0141] Fig. 9 This is a diagram showing an example of the correlation between the sound pressure and frequency of background noise.

[0142] exist Fig. 9 In the figure, the horizontal axis represents frequency and the vertical axis represents sound pressure.

[0143] The bandpass filter can be configured to extract, for example, a frequency band around the main frequency (250 Hz as an example) of the excitation waveform in the waveform generation unit 110 .

[0144] The sound pressure in the extracted frequency band (as an example, the average value of the frequency band) is provided to the second gain adjustment unit 160 as a sensing value.

[0145] The second gain adjustment unit 160 further performs a second gain adjustment, which will be described below, on the excitation waveform after the first gain adjustment.

[0146] Since the second gain adjustment adjusts the output amplitude of the excitation waveform in response to changes in background noise (drive system noise, aerodynamic noise, road noise, etc.) when the vehicle is traveling, the gain of the excitation waveform is changed according to the sensed value of the noise in the vehicle cabin.

[0147] The second gain adjustment unit 160 performs second gain adjustment based on the output of the sensing value calculation unit 150 .

[0148] The second gain adjustment unit 160 sets the gain G2 based on the sensing value output by the sensing value calculation unit 150 .

[0149] Fig.10 FIG. 1 is a diagram schematically showing an example of gain adjustment in the second gain adjustment unit.

[0150] exist Fig.10 In FIG. 1 , the horizontal axis represents the sensed value, and the vertical axis represents the gain G2 multiplied by the voltage of the excitation waveform.

[0151] The gain G2 can be configured to increase as the sensed value increases.

[0152] Gain G2 is set so that the sound pressure of the sound output from speaker 170 based on the excitation amplitude does not stand out with respect to the sound pressure of the background noise near the ears of the occupant.

[0153] Preferably, the gain G2 may be set so that the sound based on the excitation amplitude is mixed into the background noise of the vehicle and reaches a sound pressure level that the occupant can hear unconsciously.

[0154] The output value (voltage) A of the excitation waveform after the first gain adjustment and the second gain adjustment described above is expressed as Equation 2.

[0155] Output value A = waveform generation unit output value × gain G1 × gain G2 = waveform generation unit output value × log (absolute value of stroke differential value ΔS × coefficient k) × gain G2 (Formula 2) Speaker 170 is a vibration device that is disposed in the vehicle cabin and uses output value A to vibrate the air around the occupants in the vehicle cabin to generate sound.

[0156] The arrangement of the speaker 170 will be described in detail later.

[0157] Speaker 170 may be configured to be shared with a speaker used for sound reproduction of a car audio system, for example.

[0158] In addition, the information delivery device 100 may be provided with a dedicated speaker 170 .

[0159] Fig.11 It is a diagram schematically showing the arrangement in the cabin of a vehicle in which the information transmission device according to the first embodiment is installed.

[0160] Inside the vehicle compartment 200 , a driver's seat 210 , a passenger seat 220 , a rear seat 230 , a dashboard 240 , and the like are provided.

[0161] The driver's seat 210 and the passenger seat 220 are front seats disposed at the front of the vehicle compartment.

[0162] The driver's seat 210 and the passenger seat 220 are arranged side by side in the vehicle width direction.

[0163] exist Fig.10 In the illustrated example, the vehicle is a so-called right-hand drive vehicle, and the driver's seat 210 is provided on the right side and the passenger seat 220 is provided on the left side relative to the left-right center of the vehicle body.

[0164] The driver's seat 210 and the passenger seat 220 each include a cushion portion for placing the occupant's buttocks and thighs, a seat back portion disposed behind the occupant's back, and a headrest portion provided behind the occupant's head.

[0165] The rear seat 230 is a long seat arranged behind the driver's seat 210 and the passenger seat 220 .

[0166] The rear seat 230 can accommodate, for example, two passengers sitting side by side transversely.

[0167] The rear seat 230 includes a cushion portion on which the buttocks and thighs of the occupant are placed, a seat back portion disposed behind the back of the occupant, and a headrest portion provided behind the head of the occupant.

[0168] The right side seating portion of the rear seat 230 is arranged behind the driver's seat 210 , and the left side seating portion is arranged behind the passenger seat 220 .

[0169] The instrument panel 240 is provided near the front end of the vehicle interior 200 and houses, for example, an instrument panel, a ventilation, air-conditioning and heating device, an infotainment device, and the like.

[0170] The instrument panel 240 is arranged to face the passengers seated in the driver's seat 210 and the passenger seat 220 .

[0171] exist Fig.11 In the illustrated example, four speakers 170 are provided in a separated manner in the front, rear, left, and right sides of the vehicle interior 200 , for example.

[0172] In the following description, each speaker 170 is denoted by a suffix corresponding to the position.

[0173] Right front speaker 170FR is disposed near the right end portion of instrument panel 240 .

[0174] The speaker 170FR is a directional speaker directed toward the head (ear) of the occupant sitting in the driver's seat 210 .

[0175] The left front speaker 170FL is arranged near the left end portion of the instrument panel 240 .

[0176] Speaker 170FL is a directional speaker directed toward the head (ear) of the occupant sitting in passenger seat 220 .

[0177] The right rear speaker 170RR is arranged at the headrest portion of the driver's seat 210 .

[0178] Speaker 170RR is a directional speaker that is directed toward the head (ear) of the occupant sitting on the right side of rear seat 230 .

[0179] The left rear speaker 170RL is disposed in the headrest portion of the passenger seat 220 .

[0180] Speaker 170RL is a directional speaker that is directed toward the head (ear) of the occupant sitting on the left side of rear seat 230 .

[0181] In the first embodiment, through the above structure, when the driver steps on the accelerator pedal 40 (acceleration operation) or returns (deceleration operation) to cause a change in the stroke S of the accelerator pedal 30, a sound with an amplitude corresponding to the differential value ΔS of the stroke S is emitted from the speaker 170 to the occupant.

[0182] Since this sound is masked by the running sound of the vehicle (background noise), it is difficult for the occupants to consciously recognize it as a sound, but the occupants can unconsciously foresee the vehicle behavior accompanied by the occurrence of fore-and-aft acceleration and pitch.

[0183] According to the first embodiment described above, the following effects can be obtained.

[0184] (1) By generating a sound whose sound pressure increases in response to an increase in the absolute value of the differential value ΔS of the stroke S of the accelerator pedal 40, it is possible to use the sound to make the occupants anticipate the occurrence of behavior in the early stage of vehicle acceleration or deceleration before the vehicle actually generates longitudinal acceleration, pitch angle, etc., wherein the stroke S of the accelerator pedal 40 is a parameter related to at least one of the driving force of the motor generator 31 and the braking force of the regenerative braking.

[0185] This improves the predictability of the vehicle behavior by the occupants, and prevents the occupants from feeling a sense of abruptness regarding the vehicle behavior.

[0186] Therefore, the occupant can prepare by applying force to the body before the acceleration or the like occurs, and can prevent the seated posture from being unexpectedly unstable.

[0187] (2) Since the excitation waveform has a main frequency in the frequency band of 100 to 400 Hz, more preferably 150 to 300 Hz, it is possible to use Pacinian corpuscles, which are highly sensitive in the audible range and highly sensitive in terms of skin sensation, etc., and the occupant's sound perception and skin sensation recognition based on sound become better. Therefore, information can be transmitted to the occupant more reliably.

[0188] (3) By using a logarithmic function to set the gain G1 according to the absolute value of the differential value ΔS of the stroke S of the accelerator pedal 40, a large gain G1 can be set even in a region where the absolute value of the differential value ΔS is relatively small, and information can be appropriately transmitted to the occupant even in the early stage of acceleration or deceleration when the stroke S and the differential value ΔS are small.

[0189] In addition, it is possible to prevent the output gain from becoming excessively large in a region where the absolute value of the differential value ΔS is large.

[0190] (4) By setting the gain G2 so that the sound pressure generated by the excitation of the speaker 170 does not stand out at the ear of at least one occupant relative to the background noise of the vehicle when the vehicle is running, the sound generated by the excitation of the speaker 170 is buried in the background noise of the vehicle, thereby preventing the occupant from feeling irritated and enabling information to be appropriately transmitted.

[0191] (5) In a configuration in which an acceleration operation is performed by a pedaling action starting from a predetermined position of a single accelerator pedal 40, and a braking operation is also performed by a return operation starting from the predetermined position, by making the output gain set based on the return action larger than the output gain set based on the pedaling operation, the output gain can be increased on the return operation side of the pedal where the driver is less likely to feel the reaction force, and the vehicle behavior accompanying deceleration can be appropriately anticipated.

[0192] <Second Embodiment> Next, a second embodiment of the information transmission device to which the present invention is applied will be described.

[0193] In each of the embodiments described below, the same reference numerals are assigned to the same parts as those in the previous embodiments, and the description thereof will be omitted, and mainly the differences will be described.

[0194] The information transmission device of the second embodiment is provided in a vehicle that performs a driving operation (acceleration operation) through an accelerator pedal and a braking operation (deceleration operation) only through a brake pedal independent of the accelerator pedal, thereby replacing the structure in which a single pedal is used to control the driving force and the braking force as in the above-described first embodiment.

[0195] In the second embodiment, the output gain setting of the excitation waveform corresponding to the differential value of the operation amount (stroke) of the accelerator pedal and the output gain setting of the excitation waveform corresponding to the differential value of the operation amount (stroke) of the brake pedal are independently set.

[0196] It should be noted that the output of the excitation waveform corresponding to the operation amount of the accelerator pedal and the output of the excitation waveform corresponding to the operation amount of the brake pedal can be performed together, but it can also be configured to perform only either one of them.

[0197] In the second embodiment described above, the same effects as those of the first embodiment (except for the effect described in item (5)) can also be obtained.

[0198] <Third Embodiment> Next, a third embodiment of the information transmission device to which the present invention is applied will be described.

[0199] In the third embodiment, the vehicle has a function of performing autonomous driving such as steering operation and acceleration / deceleration operation independently of the driver's driving operation.

[0200] The vehicle of the third embodiment has, in addition to the structure of the vehicle of the first embodiment, an autonomous driving control unit (not shown).

[0201] The autonomous driving control unit uses various sensors such as a stereo camera device, a millimeter-wave radar device, and a laser scanner device, and a high-precision 3D map to recognize the environment around the vehicle.

[0202] The autonomous driving control unit generates an autonomous driving scenario including information related to the driving route, speed, etc. of the vehicle based on the recognized environment.

[0203] Based on the autonomous driving scenario, the autonomous driving control unit provides instructions to the power steering control unit 50, the motor generator control unit 30, the brake control unit 10, etc. to control the steering and acceleration / deceleration of the vehicle.

[0204] In the third embodiment, the information transmission device 100 uses the request value of the driving force applied from the automatic driving control unit to the electric generator control unit 30 (a parameter related to the driving force) and the request value of the braking force applied from the automatic driving control unit to the brake control unit 10 (a parameter related to the braking force) as input, thereby replacing the stroke S of the accelerator pedal 40 in the first embodiment.

[0205] As the requested value of the driving force, for example, a requested torque value of the motor generator can be used.

[0206] As the requested value of the braking force, for example, a target deceleration of the vehicle, a target brake fluid pressure of a hydraulic brake, a regenerative power generation amount of a motor generator when regenerative braking is used, etc. can be used.

[0207] According to the third embodiment described above, in a vehicle performing automatic driving, when acceleration or deceleration based on automatic driving control is started, a sound corresponding to the absolute value of the differential value of a parameter related to the driving force and the braking force is also generated, thereby enabling the occupants to foresee the vehicle behavior accompanied by the front and rear acceleration, the pitch angle, etc., and preventing the occupants from feeling abrupt about the vehicle's behavior.

[0208] (Variation) The present invention is not limited to the above-described embodiment, and various modifications and changes can be made, and these modifications and changes are also within the technical scope of the present invention.

[0209] (1) The configurations of the information transmission device and the vehicle are not limited to the above-described embodiments, and can be modified as appropriate.

[0210] For example, the hardware configuration of the information transmission device and the specific method of adjusting the gain of the excitation waveform are not limited to the configurations of each embodiment, and can be modified as appropriate.

[0211] (2) In the first embodiment, for example, the stroke of the pedal is used as a parameter related to the driving force of the driving device and the braking force of the braking device. However, the parameter is not limited thereto and can be changed as appropriate.

[0212] For example, the requested torque (target torque) of the running power source can be used as the parameter related to the driving force. When the running power source is an internal combustion engine, the throttle opening, fuel injection amount, etc. can be used as the parameter related to the driving force.

[0213] As parameters related to the braking force, for example, brake fluid pressure of a hydraulic brake (typically master cylinder pressure), a depression amount (stroke) of a brake pedal for brake operation by foot operation, a depression force, etc. can be used.

[0214] (3) In each embodiment, as an example, the level of the background noise of the vehicle is acquired using a microphone, but the present invention is not limited thereto and the level of the background noise may be acquired using other methods. For example, the level of the background noise may be estimated based on the acceleration of the unsprung portion of the vehicle related to the input from the road surface and the output value of the torque sensor of the steering device (torsion bar torque).

Claims

1. An information transmission device, It is characterized in that Installed in the vehicle, The vehicle includes a driving device for driving wheels and a braking device for braking the wheels. The information transmission device comprises: a parameter detection unit that detects a parameter related to at least one of the driving force of the driving device and the braking force of the braking device; an excitation waveform generating unit that generates an excitation waveform; an excitation unit for exciting the air around the occupant using the excitation waveform; as well as A gain adjustment section increases the output gain of the excitation waveform in response to an increase in the absolute value of the differential value of the parameter.

2. The information transmission device according to claim 1, It is characterized in that The excitation waveform has a main frequency included in a frequency band of 100 to 400 Hz.

3. The information transmission device according to claim 1 or 2, It is characterized in that An increase rate of the output gain in the gain adjustment unit with respect to an increase in the absolute value of the differential value becomes maximum in a region where the absolute value of the differential value is small, and decreases as the absolute value of the differential value increases.

4. The information transmission device according to claim 1 or 2, It is characterized in that The gain adjustment unit sets the output gain so that the sound pressure generated by the excitation of the excitation unit does not stand out at the ear of at least one occupant relative to background noise when the vehicle is traveling.

5. The information transmission device according to claim 1 or 2, It is characterized in that The vehicle includes an input device that performs an acceleration operation by a stepping action from a predetermined position of a single pedal and also performs a braking action by a return action from the predetermined position. The gain adjustment unit makes the output gain set according to the returning motion larger than the output gain set according to the stepping motion.

Images