Airbag controller and method

A controller for a vehicle includes a processor and a memory storing processor-executable instructions. The processor of the controller is programmed to receive a side-impact signal representing a collision to a side of the vehicle, receive an occupancy signal indicating that a first rear seat of the vehicle is occupied, and send an output control signal to deploy an airbag between a front seat adjacent the side of the vehicle and a second rear seat adjacent the side of the vehicle in response to the side-impact signal and the occupancy signal only when the second rear seat is unoccupied.

BACKGROUND

Vehicles, such as automobiles, may include airbags designed to inflate and be impacted by occupants of a rear seat during a front or side impact of the vehicle. For example, a side curtain airbag may deploy from above a door during a side collision, and the side curtain airbag may be impacted by an occupant in the rear seat adjacent to the side curtain airbag. For another example, an airbag may deploy rearward from a seatback of a front seat during a front impact, and an occupant in the rear seat behind the front seat may impact the airbag.

During a side impact to a side of the vehicle opposite an occupant sitting in a rear seat, the occupant may be urged laterally toward the impacted side by the force of the impact. While a seatbelt may mitigate some effects of a side impact to the occupant seated on the far side from the impact, not all states mandate wearing seat belts in the rear seats, and not all occupants choose to wear seatbelts.

DETAILED DESCRIPTION

With reference to the Figures, wherein like numerals indicate like parts throughout the several views, a controller32for a vehicle30includes a processor and a memory storing processor-executable instructions. The processor of the controller32is programmed to receive a side-impact signal representing a collision to a side34of the vehicle30, receive an occupancy signal indicating that a first rear seat of the vehicle30is occupied, and send an output control signal to deploy an airbag36between a front seat42adjacent the side34of the vehicle30and a second rear seat adjacent the side34of the vehicle30in response to the side-impact signal and the occupancy signal only when the second rear seat is unoccupied. (The adjectives “first,” “second,” and “third” are used throughout this document as identifiers and are not intended to signify importance or order.)

Deploying the airbag36during a side impact may reduce the likelihood of injury to an occupant from moving toward the side34at which the impact occurred. Moreover, the same airbag36may be deployed during a front impact. Using the same airbag36for both impact scenarios is more efficient and cost-effective.

With reference toFIG. 1, the vehicle30may include a front38, which is an end of the vehicle30facing in a forward direction of travel of the vehicle30, and two sides34, which are lateral from the direction of the forward travel of the vehicle30.

With reference toFIGS. 2A-E, the vehicle30includes a passenger cabin40to house occupants, if any, of the vehicle30. The passenger cabin40includes one or more front seats42disposed at a front of the passenger cabin40and one or more rear seats44,46,48disposed behind the front seats42. The passenger cabin40may also include third-row seats (not shown) at a rear of the passenger cabin40. A ceiling50may be disposed above the passenger cabin40.

InFIGS. 2A-E, the front seats42are shown to be bucket seats, and the rear seats44,46,48are shown to be bench seats, but the seats may be other types. The row of rear seats may include a left rear seat44, a middle rear seat46, and a right rear seat48. The terms “front seat” and “rear seat” refer to the position of a seat in a vehicle-forward direction relative to a different row of seating. In other words, if the vehicle30has three rows of seating, the second row in the vehicle-forward direction may be rear seats44,46,48relative to the first row and front seats42relative to the third row, and the third row may be rear seats44,46,48relative to the second row.

Each seat may include a seatback52, a seat bottom (not numbered), and a headrest. The headrest may be supported by the seatback52and may be stationary or movable relative to the seat back. The seatback52may be supported by the seat bottom and may be stationary or movable relative to the seat bottom. The seatback52, the seat bottom, and/or the headrest may be adjustable in multiple degrees of freedom. Specifically, the seatback52, the seat bottom, and/or the headrest may themselves be adjustable, in other words, adjustable components within the seatback52, the seat bottom, and/or the headrest, and/or may be adjustable relative to each other.

The airbags36may be configured to deploy between the front seats42and the rear seats44,46,48. The airbags36may be disposed in the seatbacks52of the front seats42, as shown inFIGS. 2A-E, or some or all of the airbags36may be disposed in the ceiling50above the front seats42.

The airbag36may be formed of any suitable airbag material, for example, a woven polymer. For example, the airbag36may be formed of woven nylon yarn, for example, nylon 6-6. Other suitable examples include polyether ether ketone (PEEK), polyetherketoneketone (PEKK), polyester, or any other suitable polymer. The woven polymer may include a coating, such as silicone, neoprene, urethane, and so on. For example, the coating may be polyorgano siloxane.

The airbags36may have an undeployed state, shown inFIGS. 2B, 2C, and2E; a first deployed state, shown inFIG. 2A; and a second deployed state, shown inFIG. 2D. In the undeployed state, the airbag36is folded and stored in the seatback52or the ceiling50. In the first and second deployed states, the airbag36extends from the seatback52or the ceiling50and is disposed between the seatback52of the front seat42and the rear seat44,46,48. A distance the airbag36extends away from the front seat42is longer for the airbag36in the first deployed state than the airbag36in the second deployed state. The difference between the first and second deployed states may be achieved by inflation patterns, tethers, vents, and/or release pins.

With reference toFIG. 3, an inflator54may be connected to the airbag36. In response to receiving a signal from, e.g., the controller32, the inflator54may inflate the airbag36with an inflatable medium, such as a gas. The inflator54may be, for example, a pyrotechnic inflator that uses a chemical reaction to drive inflation medium to the airbag36. The inflator54may be of any suitable type, for example, a cold-gas inflator.

A control system56may include the controller32, the inflator54, an impact sensor58, and an occupancy sensor60, all in communication through a communications network62.

The controller32may be a microprocessor-based controller. The controller32may include a processor, memory, etc. The memory of the controller32may store instructions executable by the processor. The controller32may be in communication with the inflator54, the impact sensor58, and the occupancy sensor60. The controller32may be in communication with the airbag36via the inflator54.

The control system56may transmit signals through a communications network62such as a controller area network (CAN) bus, Ethernet, Local Interconnect Network (LIN), and/or by any other wired or wireless communications network.

The impact sensor58may be in communication with the controller32. The impact sensor58is adapted to detect an impact to the vehicle30. The impact sensor58may be of any suitable type, for example, post-contact sensors such as accelerometers, pressure sensors, and contact switches; and pre-impact sensors such as radar, lidar, and vision-sensing systems. The vision systems may include one or more cameras, CCD image sensors, CMOS image sensors, etc. The impact sensor58may be located at numerous points in or on the vehicle30. The impact sensor58may be adapted to detect a direction of impact to the vehicle30, or multiple impact sensors58may detect impacts from different directions.

The occupancy sensor60is configured to detect occupancy of the seats. The occupancy sensor60may be visible-light or infrared cameras directed at the seats, weight sensors inside the seats, sensors detecting whether seat belts for the seats are buckled or unspooled, or other suitable sensors. The occupancy sensor60is in communication with the controller32via the communications network62.

FIG. 4is a process flow diagram illustrating an exemplary process400for responding to an impact to the vehicle30. The process400begins in a decision block405. In the decision block405, the controller32determines whether an impact has occurred and, if so, a direction of the impact. If the controller32receives a side-impact signal representing a collision to the side34of the vehicle30from the impact sensor58, then the controller32determines that a side impact has occurred. If the controller32receives a front-impact signal representing a collision to the front38of the vehicle30from the impact sensor58, then the controller32determines that a front impact has occurred. If the controller32receives no impact signals, then the controller32determines that an impact has not occurred, and, in a block435, the controller32does not send any signal to deploy the airbag36.

In the event of a side impact, next, in a decision block410, the controller32determines whether the rear seat spaced away from the side34experiencing the impact is occupied. In describing blocks410-420, the “first rear seat” refers to the rear seat spaced away from the side34experiencing the impact, and the “second rear seat” refers to the rear seat adjacent the side34experiencing the impact. If the impact is to the right side34of the vehicle30, the first rear seat is the left or middle rear seat44,46, and the second rear seat is the right rear seat48. The “third rear seat” refers to the middle rear seat46. If the controller32receives an occupancy signal from the occupancy sensor60indicating that the first rear seat of the vehicle30is occupied, or if the controller32receives an occupancy signal indicating that the third rear seat between the first and second rear seats is occupied, then the process400moves to the decision block415. If the controller32does not receive an occupancy signal with respect to the first or third rear seats, then, in the block435, the controller32does not send any signal to deploy the airbag36between the front seat42and the second rear seat.

After the decision block410, if the first or third rear seat is occupied, next, in a decision block415, the controller32determines whether the second rear seat is occupied. If the controller32receives a second occupancy signal from the occupancy sensor60indicating that the second rear seat is occupied, then, in the block435, the controller32does not send any signal to deploy the airbag36between the front seat42and the second rear seat. If the controller32determines that the second rear seat is unoccupied based on a lack of a signal indicating that the second rear seat is occupied from the occupancy sensor60, then the process400proceeds to a block420.

After the decision block415, if the second rear seat is unoccupied, next, in the block420, the controller32sends an output control signal to the inflator54to deploy the airbag36to the first deployed state between the front seat42adjacent the side34of the vehicle30and the second rear seat adjacent the side34of the vehicle30. The controller32may also send an output control signal to, e.g., the release pins so that the airbag36inflates to the first deployed state. The effect of the blocks405-420is that the controller32sends the output control signal in response to the side-impact signal and the occupancy signal for the first or third rear seat only when the second rear seat is unoccupied.

If the controller32determines in the decision block405that a front impact has occurred, next, in a decision block425, the controller32determines whether the rear seat is occupied. This step may occur for each of the rear seats44,46,48adjacent the sides34of the vehicle30. If the controller32receives an occupancy signal indicating that the rear seat is occupied, the process400proceeds to a block430. If the controller32determines that the rear seat is unoccupied based on a lack of a signal indicating that the rear seat is occupied, the controller32does not send any signal to deploy the airbag36between the front seat42and the rear seat.

After the decision block425, if the rear seat is occupied, next, in the block430, the controller32sends an output control signal to deploy the airbag36to the second deployed state between the front seat42and the rear seat. This step may occur for each of the rear seats44,46,48. The controller32may also send an output control signal to, e.g., the release pins so that the airbag36inflates to the second deployed state. The effect of the blocks405and425-430is that the controller32sends the output control signal in response to the front-impact signal and the occupancy signal.