Wireless airbag control system

Abstract

A wireless airbag control system includes a central master electronic control module having an RF transceiver. One or more slave nodes are provided, each slave node being associated with an airbag that is mounted to perform an operating function with respect to a mechanical device. Each slave node further includes an RF transceiver, a central processing unit and a CAN controller. Two-way communication is shared between the slave nodes and the master electronic control module on a prioritized message basis.

Claims

1. A wireless airbag control system comprising: a) a central master electronic control module having an RF transceiver and including a processor to selectively communicate prioritized messages to a plurality of slave nodes; b) a plurality of airbag devices capable of repeatable inflation and deflation, wherein each of said airbag devices is mounted to perform a controlled, repeatable operating function to deploy and retract an attached mechanical device; c) a plurality of slave nodes, each slave node being associated with one of said airbag devices, wherein each slave node further comprises an RF transceiver, a central processing unit, and a CAN controller; wherein each slave node further includes a terminating resistor; and wherein each slave node is connected to operate a plurality of associated airbag valve control devices to selectively allow air to enter and leave each airbag.

2. A wireless airbag control system as in claim 1 wherein each slave node is connected to a plurality of pressure sensors and wherein said control system controls air pressure in a plurality of associated airbags and adjusts the force exerted by each associated airbag to correlate actual load with a commanded load.

3. A wireless airbag control system as in claim 1 wherein each slave node is connected to one or more sensors for determining airbag position or force being applied.

4. A wireless airbag control system as in claim 3 wherein each said sensor for determining airbag force being applied is a strain gauge and wherein said control system controls air pressure in each associated airbag based on signals from each said sensor to correlate pressure with a commanded set point.

5. A wireless airbag control system as in claim 1 wherein each slave node is connected to one or more pressure sensors and wherein said control system controls air pressure in each said associated airbag to adjust the force exerted to correlate actual load with a commanded load.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The foregoing features and advantages of the invention will become apparent to those skilled in the art from the following detailed description of one or more preferred embodiments, especially when considered in conjunction with the accompanying drawings in which like numerals depict like parts:

(2) FIG. 1 is a schematic representation of a control system for a multi-unit arrangement using a wireless airbag control system to selectively operate one or more devices in a plurality of devices that have airbag actuators;

(3) FIG. 2 is a schematic representation of a wireless airbag control system in accordance with the invention showing single and dual-acting airbags;

(4) FIG. 3 is a schematic representation that depicts a control system mounted on a uni-directional or single acting airbag unit having a single inflatable chamber;

(5) FIG. 4 is a schematic drawing similar to FIG. 3 for a bi-directional dual-chamber airbag unit; and

(6) FIG. 5 is a schematic diagram of a control system associated with a processor housing for the airbag of FIG. 4.

DETAILED DESCRIPTION

(7) The detailed description of the illustrative embodiments is intended to illustrate representative examples of the inventive concepts and is not intended to exhaust or limit the scope of those concepts. The examples are to be read in connection with the accompanying drawings, which are to be considered part of the entire written description of this invention. In the description, relative terms such as “lower”, “upper”, “horizontal”, “vertical”, “above”, “below”, “up”, “down”, “top” and “bottom”, “left” and “right”, as well as derivatives thereof (e.g., “horizontally”, “downwardly”, “upwardly”, etc.) should be construed to refer to the orientation as then described or as shown in the drawings under discussion. These relative terms are for convenience of description and do not require that the apparatus be constructed or operated in a particular orientation. Terms such as “connected”, “connecting”, “attached”, “attaching”, “join” and “joining” are used interchangeably and refer to one structure or surface being secured to another structure or surface or integrally fabricated in one piece, unless expressively described otherwise.

(8) It should be noted that inflatable pneumatic operators in the form of conventional airbags have been found to be a preferred type of pneumatic operator, but other such devices could also be used.

(9) The term “airbag”, as used herein, is defined to mean any type of inflatable pneumatic operator, without limitation, including convoluted and non-convoluted devices with single and multiple air access ports, and ports at different locations. Single and double-acting units are also included.

(10) The schematic representation of FIG. 1 depicts a multi-node wireless airbag control system generally at 10 having central master electronic control module 12 which may be located in a vehicle or at a machine operator's station and which communicates with a plurality of devices that use airbag actuators 10 using a wireless communication system that includes a plurality of slave modules or electronic control units (ECUs) also known as nodes 14, all of which are controlled by wireless transceivers 16 which communicate with a control module transceiver 18. A power supply for the master electronic control module is shown at 20. Each node further includes a power supply 22; at least one output to an airbag actuator as at 24 and receives input form each connected device as at 26. While FIG. 1 depicts 12 controlled nodes, such a setup can be used in a system that treats any number of devices that use airbag actuators.

(11) It will be appreciated that the complexity of an Electronic Control Unit (ECU) or node can range from a simple I/O device up to an embedded computer with a CAN interface and sophisticated software. Each node requires a:

(12) 1) Central processing unit, microprocessor, or host processor The host processor decides what the received messages mean and what messages it wants to transmit. Sensors, actuators and control devices can be connected to the host processor.

(13) 2) CAN controller; often an integral part of the microcontroller Receiving: the CAN controller stores the received serial bits from the bus until an entire message is available, which can then be fetched by the host processor (usually by the CAN controller triggering an interrupt). Sending: the host processor sends the transmit message(s) to a CAN controller, which transmits the bits serially onto the bus when the bus is free.

(14) 3) Transceiver Defined by ISO 11898-2/3 Medium Access Unit [MAU] standards Receiving: it converts the data stream from CANbus levels to levels that the CAN controller uses. It usually has protective circuitry to protect the CAN controller. Transmitting: it converts the data stream from the CAN controller to CANbus levels.

(15) Each node is able to send and receive messages, but not simultaneously. A message or Frame consists primarily of the ID (identifier), which represents the priority of the message, and up to eight data bytes. A CRC, acknowledge slot [ACK] and other overhead are also part of the message. The improved CAN FD extends the length of the data section to up to 64 bytes per frame. The message is transmitted serially onto the bus using a non-return-to-zero (NRZ) format and may be received by all nodes.

(16) The devices that are connected by a CAN network are typically sensors, actuators, and other control devices. These devices are connected to the bus through a host processor, a CAN controller, and a CAN transceiver.

(17) At the beginning of every message sent on a CANbus system the first few bits of information is a priority level. When a new message cycle begins every node sends out its priority and is also listening to every other nodes message priority. At the end of the message priority phase of the message only the node with the highest priority message continues to transmit and all of the other nodes receive the message. Every node hears every message, but only acts upon commands that are directed at it, completely ignoring the rest. In conventional wiring harnesses every node sends its information to nodes it needs to talk to using individual wires to each other node. On a system where there is a great plurality of nodes, a CANbus system eliminates an abundance of wires that can be the cause of a great number of problems.

(18) The application of the present invention is designed to control airbag actuators with internal valves, preferably with some kind of sensor to determine how much load the airbag is creating. As indicated, in order to connect airbags to a CANbus system, each airbag becomes a node. Each airbag node requires a processor that can receive and send CANbus format messages. The processor must also be able to send and receive analog and or digital signals to the valves and sensors depending on the system requirements. Each airbag/node also requires a terminating resistor. The ones that are depicted in FIGS. 3 and 4 are external and can be removed to continue the chain to another node.

(19) In some alternate applications, a sensor may not be required as, for example, on a retractable auxiliary axle associated with a heavy truck. The only thing that is required is an up or down command and opening the proper valve to inflate the proper airbag. In some cases, a sensor could be used to fine tune the amount of force being applied. Pressure sensors to determine the air pressure inside the airbags or strain gauges used to determine the amount of force being applied to an object can be used. Whatever the type of sensor or units of measure that are being used to quantify the load the airbag is creating, the processor needs to be able to correlate actual load against commanded load. The processor should also be able to open and close the appropriate valves on the airbag until the actual load is within a predetermined system tolerance of the commanded load.

(20) As shown in the figures, the processor will be located in a housing attached to the airbag. Inside the processor housing the processor will have memory capacity to retain information that will be necessary for the processor to do its job. The processor will receive and send messages in CAN format, generate analog or digital signals from the CAN format messages it receives. The processor will send and receive a plurality of signals in analog and digital formats according to system requirements. The processor can be operatively connected to a single or a plurality of sensors to determine the actual load the airbag or airbags are creating. The processor will also be operatively connected to one or a plurality of control valves to change the position of the airbag or airbags. This will allow the processor to make commanded changes to the position of the airbag or the force the airbag is creating according to the information it is receiving from the sensors so that the commanded position or force matches what the sensor reads. The number of sensors and control valves will depend on the type of airbag used and its intended purpose.

(21) The processor inside the processor housing will be operatively coupled to a wireless transceiver to send and receive CAN messages for mobile applications or applications that are not conducive to running a CANbus cable. The processor housing is provided with an external connection for a terminating resistor. Optionally, the terminating resistor can be mounted inside the processor housing for certain applications. External terminating resistors allow the airbag nodes to also be connected to a wired CANbus system.

(22) The present invention uses wireless radio transceivers to send CANbus messages between the control interface and the individual airbags or sets of airbags. To do this, as indicated, every airbag becomes a CANbus node with a processor.

(23) A schematic wireless airbag control system diagram is shown in FIG. 2. The system includes a virtual, terminal or control panel 30 that coordinates and controls operation of the system through wired CANbus system 32 and control transceiver 34 that communicates with wireless transceivers 36, 38, 40, and 42 which are connected to control processors in housings 44, 46, 48 and 50, respectively. Two types of dual-acting airbags are shown at 52 and 54 in which one or both sides can be inflated. Airbag 52 is non-convoluted and airbag 54 is convoluted. Likewise, single-acting airbags are shown at 56 and 58. A common electric power system used to operate valving associated with inflating and deflating the airbags is designated 60.

(24) FIGS. 3 and 4 depict views of un-directional or single-acting and bi-directional or double-acting airbags, respectively, with attached wireless CANbus controls. This, in FIG. 3, there is shown a single-acting airbag unit 70 with an attached processor housing 72, associated radio transceiver 74 and external terminating resistor 76. A processor controller, not shown, is connected to an airbag valve solenoid system 78 by a signal wire 80 to inflate and exhaust the single expanding bag portion 82. A pressure sensor is shown at 84.

(25) FIG. 4 is similar to FIG. 3 depicting a bi-directional or double-acting airbag 90 with inflatable chamber aspects 92 and 94. This unit includes processor housing 96 that houses a processor that controls an airbag solenoid system indicated by 98 with connection signal wire 100. Signal wires 102 and 104 connect upper and lower pressure sensors 106 and 108. A radio transceiver is shown at 110 and a terminal resistor at 112.

(26) FIG. 5 is a schematic diagram of a control system associated with a processor housing shown at 120. It includes an internal processor or plurality of processors 122. The processor or processors connect to communicate with a memory 124 and an electric power input 126. Two-way communication is also shown with an input/output (I/O) module 128 which connects the processor(s) with an RF transceiver 130 and a terminal resistor 132. Connection is also made with airbag valve outputs at 134 with signals to upper and lower valves (FIG. 4) at 136 and 138. Information is received from one or more airbag sensors at 140 through inputs at 142.

(27) In operation, the master electronic control module is operated to coordinate the operation of each associated airbag node and can selectively initiate inflation, deflation, adjust pressure, etc., of one or a plurality of airbags to coordinate operation of a plurality of airbag actuators on a mechanism(s) on any given mechanical system. Communication is by sending and receiving messages using RF transceivers and prioritized messages.

(28) This invention has been described herein in considerable detail in order to comply with the patent statutes and to provide those skilled in the art with the information needed to apply the novel principles and to construct and use embodiments of the example as required. However, it is to be understood that the invention can be carried out by specifically different devices and that various modifications can be accomplished without departing from the scope of the invention itself.