Field of the invention:

[0001] The present invention relates to a helmet and method for selecting and playing desired sound in the same.

Background of the invention:

[0002] In two wheelers, external noise is highly disturbing for a driver/rider. There are solutions for noise cancellation in helmets, but using an active noise cancellation technique. The active noise cancellation can be annoying because it may generate some additive noise in few scenarios instead of complete noise cancellation. The active noise cancellation captures the noise inside the helmet using a microphone and removes the noise by generating the anti-noise of the same signal, such that it gets cancelled out inside the helmet shell. A selective noise isolation is very complex in this approach, as the signal needs to be separated/identified first, followed by creating the anti-noise of the signal.

[0003] A patent literature US20050117771 discloses a sound production systems and methods for providing sound inside a headgear unit. Methods for generating a directional sound environment include providing a headgear unit having a plurality of microphones thereon. A sound signal is detected from the plurality of microphones. A transfer function is applied to the sound signal to provide a transformed sound signal, and the transformed sound signal provides an approximation of free field hearing sound at a subject's ear inside the headgear unit.

Brief description of the accompanying drawings:

[0004] An embodiment of the disclosure is described with reference to the following accompanying drawings,

[0005] Fig. 1 illustrates a block diagram of a helmet, according to an embodiment of the present invention, and [0006] Fig. 2 illustrates a method for selecting and playing a desired sound in the helmet, according to the present invention.

Detailed description of the embodiments:

[0007] Fig. 1 illustrates a block diagram of a helmet, according to an embodiment of the present invention. The helmet 100, comprises at least one microphone 104 located on the helmet 100 or on a shell 102 of the helmet 100 to detect a sound signal generated in a surrounding of the helmet 100. Further, at least one speaker 106 located on interior surface of the helmet 100. A controller 110 is provided in electronic communication with the at least one microphone 104 and the at least one speaker 106, characterized in that, the controller 110 adapted to select and play a desired sound from the detected sound signal, through the at least one speaker 106.

[0008] In accordance to an embodiment, plurality of microphones 104 are located on the shell 102 and at least two speakers 106 are provided on two sides of the interior of the helmet 100. Alternatively, stereo microphones 104 are used. The interior of the helmet 100 comprises coverings 122, such as earmuff or cushion, for the ear (pinna) of a wearer in such a manner that a complete noise isolation is obtained from the surrounding. The at least one speaker 106 is located inside the covering 122. The interior of the helmet 100 defines a cavity 108 for insertion of the wearer’s head. The cavity 108 is shown in dashed lines.

[0009] The at least one microphone 104 and the at least one speaker 106 are electrically connected to controller 110. The controller 110 is a control unit such as a microcontroller, comprising a memory element 116, a processing unit or processor 112, a transceiver unit 114 and other components as known in the art. The processor 112 executes the instructions stored in the memory element 116. The processor 112 processes the data received from the transceiver 114 or other hardware ports and the data stored in the memory element 116. [0010] The controller 110 selects and plays the desired sound based on a preference set by the wearer of the helmet 100. In order to select the desired sound, as set by the wearer, the controller 110 is adapted to process, by comparison, the detected sound signal with plurality of filters 118, each of the filter 1 18 comprises sound characteristic corresponding to the plurality of sources. The plurality of filters 118 are stored in the memory element 1 16 of the controller 110. The controller 110, then identifies and selects the desired sound from the detected sound signal based on the comparison. Example: the engine sound/noise varies for different motorcycles and for different models. Hence, an engine filter 1 18 comprises coefficients to cancel the engine noise for each mototcycle and corresponding model is stored in the memory element 116. Similarly, coefficients are stored for remaining plurality of filters 118, such as a wind filter 1 18, a siren filter 1 18, a traffic filter 1 18, etc.

[001 1] The sound signal comprises sound generated by, the plurality of sources, comprising at least one of a wind, an engine, a horn, an emergency siren and an announcement, other traffic related noises or sounds and the like. The sound signal is detected by at least one microphone 104.

[0012] In accordance to an embodiment of the present invention, the controller 1 10 processes, identifies, selects and plays the desired sound. The preference is received through the plurality of buttons (not shown) provided on the shell 102. Each button corresponds to a specific filter 118. One press activates the respective filter 118 to remove the sound, and a subsequent press deactivates the filter 118, indicating to allow the sound. The plurality of filters 1 18 are stored in the memory element 1 16 of the controller 110.

[0013] In another embodiment, the controller 110 processes, identifies, selects and plays the desired sound, but receives the preference from the wearer through an electronic device 120. The plurality of filters 1 18 are either stored in the memory element 116 of the controller 110 or in the electronic device 120. The electronic device 120 is selected from a group comprising a communication device, a smartphone, a music player, a wearable computing device and an infotainment unit of a vehicle.

[0014] In yet another embodiment of the present invention, the controller 1 10 sends the detected sound signal to the electronic device 120 through the transceiver 1 14 or through wired connection. Then, the electronic device 120 processes the sound signal, identifies and selects the desired sound, whereas the controller 110 only plays the desired sound received back from the electronic device 120.

[0015] According to an embodiment, a list of desired sound and undesired sound are frequently updated in a cloud server (not shown). The cloud server sends the updated list to the electronic device 120, through wired or wired connection.

[0016] The preference of the wearer is provided either by the buttons on the helmet 100 or through the electronic device 120. For example: In case the electronic device 120 is an infotainment unit of the two-wheeler, such as motorcycle or scooter, the buttons are provided on the infotainment unit or speedometer, either as a physical buttons or on a touch screen. In case of the electronic device 120 is a smart phone, the preference are provided through an application installed in the smart phone. The smartphone is connected to the helmet 100 through the wired, such as audio jack, micro Universal Serial Bus (USB) or wireless means known in the art, such as Bluetooth, Wi-Fi, etc. In another example, the electronic device 120 is a smart watch or smart glasses.

[0017] According to an embodiment of the present invention, the controller 110 is adapted to perform Selective Noise Cancellation (SNC) for the rider or driver. The noise corresponds to undesired sound present in the detected sound signal. The SNC is performed by using at least one of noise isolation head phones integrated inside the helmet 100 (and/or using noise isolating material inside the shell 102), and providing desired/essential sounds of the surrounding or real world to the at least one speaker 106 as electrical signals, which are captured/detected using at least one microphone 104.

[0018] In accordance to an embodiment, the controller 1 10 is adapted to combine the desired sound with an audio signal received from an electronic device 120, based on a psychoacoustic model. The controller 110 varies intensity of each of the desired sound and the audio signal to prevent masking of desired sound. The audio signal is selected from a music, a radio signal, a navigation audio, a phone call (ringtone or call during standstill) and an alarm. The psychoacoustic model is stored in the memory element 116 of the controller 110 or stored in the electronic device 120. The controller 1 10 combines or mixes the desired sound with the audio signals by analyzing the frequency contents based on psychoacoustic model, and thereby prevents the frequency masking issue. The controller 110 combines the signals in manner that, desired sound is not masked by the audio signal.

[0019] For example: consider a driver/rider is listening to an audio signal, such as radio, navigation, music, etc. in a traffic, where there is an ambulance, police vehicle, fire engine with respective siren in proximity to the vehicle . The controller 110 detects the siren along with the other desired and undesired sound signals. The controller 1 10 identifies the siren and increases the intensity of the siren, whereas the intensity of the audio signal which the wearer is listening to, is reduced. Thus, the driver/rider is aware of the surrounding emergency and rides accordingly. Once, the siren is no longer present, the controller 110 increases the intensity of the audio signal. The of increase or decrease of the intensity is calculated based on respective masking threshold for the detected sound signal, so that the rider or driver is made aware of the emergency sounds while driving. A hom and siren are considered to be mandatory desired sounds, whose intensity is controlled without human intervention. The present application is also applicable for helmets 100 worn by pillion riders. [0020] Another example comprises removal of only wind noise and allowing engine noise, or removal of engine noise and wind noise and allowing all other sounds. Thus, the controller 110 enables selection of at least one desired sound (other than mandatory sounds such as emergency siren, horn, etc.) and to filter out remaining sounds.

[0021] Fig. 2 illustrates a method for selecting and playing a desired sound in the helmet, according to the present invention. The method comprising the steps of, step 202 comprising, detecting a sound signal generated from plurality of sources in a surrounding of the helmet 100. A step 204 comprises processing, by comparison, the detected sound signal with at least one filter 118, each of the filter 118 comprises sound characteristic corresponding to the plurality of sources. A step 206 comprises, identifying a desired sound to be played and filtering out undesired sound from the detected sound signal. A step 208 comprises playing the desired sound through at least one speaker 106 in the helmet 100.

[0022] The method further comprises a step 210 comprising, combining the desired sound with an audio signal received from the electronic device 120 based on a psychoacoustic model. The combining of the desired sound and the audio signal is performed based on respective masking threshold, to ensure that the desired sound is not masked by the audio signal. In other words, the desired sound is prioritized over the audio signal, such that the wearer hears the desired sound and takes necessary action, such as moving to a side in case of an ambulance, or allowing a rear vehicle to overtake on detecting a honking, etc.

[0023] Consider an example, where there one microphone 104 and one speaker 106 arrangement on the helmet 100 is provided for each ear (left and right) of the wearer. The sound signal is detected in left and right side microphone 104. The controller 110 performs the SNC as per the preference set by the wearer and plays the desired sound through both the speakers 106. If the audio signal is also being played by the wearer, then the controller 110 combines the desired sound with the audio signal based on the psychoacoustic model and then plays through the two speakers 106. The intensity or amplitude of magnitude of the desired sound is increased and that of the audio signal is reduced for the time the desired sound is available. [0024] In accordance to an embodiment of the present invention, the present invention provides selective noise isolation or cancellation, in comparison to the active noise cancellation in the existing art. The selective noise or sound in the helmet 100 avoid distractions and enables concentration of the driver/rider. Further, the controller 110 combines the desired sound with the audio signals based on psychoacoustic analysis model to avoid masking.

[0025] It should be understood that embodiments explained in the description above are only illustrative and do not limit the scope of this invention. Many such embodiments and other modifications and changes in the embodiment explained in the description are envisaged. The scope of the invention is only limited by the scope of the claims.