GB2537680A

GB2537680A - Vehicle control system & method

Info

Publication number: GB2537680A
Application number: GB1507007.1A
Authority: GB
Inventors: Thompson Vincent
Original assignee: Ttn Tech Ltd
Current assignee: Ttn Tech Ltd
Priority date: 2015-04-24
Filing date: 2015-04-24
Publication date: 2016-10-26
Also published as: GB201507007D0

Abstract

A control system for a vehicle (1 see fig 1) includes a controller (7 see fig 1) arranged to inhibit acceleration in response to receiving an actuation input signal or signals(s); and subsequently to cease inhibiting acceleration in response to receiving at least one input signal indicative of an operational condition of a brake system (3 see fig 1), when the controller (7) determines that at least one brake system operational condition is met. The invention is aimed at reducing sudden unintended accelerations. Control steps 102, 106 for determining to inhibit a throttle may include determining if a park brake is applied, determining if the vehicle is stationary and determining door opening. Control steps 110, 111 for determining to reinstate throttle control may include determining if a footbrake is applied for a duration and determining if the park brake is released, which would for example involve handbrake release.

Description

Vehicle Control System & Method The present invention relates to a control system for a vehicle, a vehicle including the vehicle control system and a method for controlling a vehicle.

Sudden Unintended Acceleration (SUA) is the unintended, unexpected, uncontrolled acceleration of a vehicle. Typically SUA incidents occur from a stationary position or a very low initial speed, accompanied by an apparent loss of braking operating effectiveness. SUA incidents have led to catastrophic consequences, including deaths of pedestrians and occupants of the vehicles involved.

There have been many recorded incidents of SUA. There have been several studies into the causes of SUA incidents. The studies have identified two main categories of causes for SUA: I) driver error; and 2) equipment failure.

For any given incident, it is not always clear what the cause was. Drivers frequently report that the brakes failed to operate, and it was this equipment failure that led to a crash occurring. In some incidents, where a driver has blamed brake failure the subsequent investigation found no evidence of equipment failure, but instead concluded that the resulting accident occurred as a result of driver error, in particular due to pedal misapplication.

Pedal misapplication is when the driver accidently presses the accelerator pedal when he intends to apply the brakes. In this situation, the driver thinks he is applying pressure to the brake pedal, but instead is actually pressing the accelerator pedal. Because the driver is convinced that he is pressing the correct pedal and that for some reason the brake system does not appear to he working, in response to the vehicle accelerating, the driver's instinct is to press the pedal harder in an attempt to make the brake system work. This leads to increased acceleration of the vehicle, the driver often losing control of the vehicle and crashing into nearby objects and pedestrians.

SUAs frequently occur when a driver is picking up/dropping of passengers, and subsequently tries to find a gap in the traffic. What initially appears to be a sufficiently large gap to drive into, may close down more quickly than expected, causing the driver to change his mind. At the critical point in time when the driver changes his mind, the driver has his foot positioned over the accelerator pedal. However, instead of moving his foot to the brake pedal, perhaps due to the pressure of the situation, he does not do so, but rather presses on the accelerator by mistake.

hi some instances, pedal misapplication may be related to pedal design and placement, for example if the brake and accelerator pedals are too close to each other, or if the accelerator pedal is too large.

Some studies indicate that failure of some of the following equipment may cause SUA incidents to occur: unresponsive (entrapped) pedals; electronic throttle control or cruise control failure (drive-by-wire failure); and sticking throttle (unrelated to pedal position).

An unresponsive pedal may result from, for example a broken mechanical linkage or electrical connection, incursion of object below the pedal or some other mechanical interference with the pedal's operation. This can involve either the accelerator or brake pedal.

Throttle control may lag demand or may stick in a particular position. When the driver pushes harder with his right foot to overcome this, the throttle control may overcome the interference, and the vehicle may then suddenly accelerate at a much greater rate than wanted by the driver, thus creating too much power and a sudden lurch forward.

A further insight from SUA studies is that the SUA problem occurs most frequently, though not exclusively, in vehicles having automatic transmissions.

Accordingly the present invention seeks to provide a vehicle control system, vehicle and method that mitigates at least one of the aforementioned problems, or at least provides an alternative to existing systems.

According to one aspect of the invention there is provided a controller arranged to: receive at least one actuation input signal; inhibit vehicle acceleration in response to receiving the actuation input signal(s); receive at least one input signal that is indicative of an operational condition of a vehicle brake system; and cease inhibiting vehicle acceleration in response to the controller determining from the brake system input signal(s) that at least one brake system operational condition is met.

The invention prevents, or at least significantly reduces, the possibility of a SUA event occurring, for example when the vehicle is stationary and the driver wants to accelerate away from the stationary condition. In this situation, the vehicle drive source is available, for example an engine is in an idling condition. The control system achieves this by temporarily removing acceleration control from the driver, monitoring the operational status of the brake system, and only returning acceleration control to the driver when the controller determines that the or each predetei tined brake system operational condition is met.

If the driver presses the accelerator pedal without the brake system's operational condition(s) having been met, the vehicle will not accelerate.

Advantageous optional features are disclosed in the dependent claims and in the statements of invention below.

In preferred embodiments, the controller ceases inhibiting vehicle acceleration when a plurality of operational conditions are met.

The brake system includes at least one driver operated control, and the controller is arranged to cease inhibiting vehicle acceleration, at least partly, in response to the controller determining from the at least one brake system input signal that the driver operated control is operated. The driver operated control comprises one of a brake pedal and a handbrake.

The brake system includes a plurality of driver operated controls, and the controller is arranged to cease inhibiting vehicle acceleration, at least partly, in response to the controller determining from the brake system input signals that each driver operated control is operated. The plurality of driver operated controls includes at least one of a brake pedal and a handbrake.

The brake system includes a stopping brake system and the controller is arranged to receive an input signal that is indicative of an operational condition of the stopping brake system. The stopping brake system is the vehicle's normal means of slowing the vehicle, while driving.

The controller is arranged to determine from the stopping brake input signal the actuation status of the stopping brake system. That is, whether the stopping brake is applied / not applied. The controller is arranged to cease inhibiting vehicle acceleration, at least partly, in response to the controller determining from the input signal that the stopping brake system is applied.

The stopping brake system includes a stopping brake and a driver operated control for actuating the stopping brake. The driver operated control is typically a foot operated control, such as a brake pedal. The controller is arranged to cease inhibiting vehicle acceleration, at least partly, in response to the controller determining from the brake system input signal(s) that at least one of the stopping brake and the driver operated control is applied. Accordingly, if the driver accidently presses the accelerator pedal instead of the brake pedal, the vehicle does not accelerate, since it is a necessary condition of having acceleration control returned to the driver that the brake pedal is pressed first. This prevents, or at least significantly reduces the possibility of an SUA event occurring from a stationary condition. In preferred embodiments the controller is arranged to cease inhibiting vehicle acceleration, at least partly, in response to the controller determining from the input signal that the stopping brake system is applied for a period of time that is greater than or equal to a predetermined period of time. This requires the driver to press brake pedal for at least a predetermined period of time, for example at least 1 second, preferably at leas( 1.5 seconds, and more preferably still at least 2 seconds, before acceleration control is returned to the driver. This provides an additional safety margin The vehicle brake system includes a park brake system and the controller is arranged to receive an input signal that is indicative of an operational condition of the park brake system.

The controller is arranged to determine from the input signal the actuation status of the park brake system. That is, whether the park brake is engaged / disengaged. The controller is arranged to cease inhibiting vehicle acceleration, at least partly, in response to the controller determining from the park brake input signal that the park brake system is disengaged. Thus, in preferred embodiments, the driver is required to initially apply the park brake when the vehicle comes to a halt, and to subsequently disengage the park brake in order to have acceleration control returned. Accordingly, if the driver stops the vehicle and does not engage the park brake system within a predetermined period of time, the vehicle cannot be accelerated.

The park brake system includes a park brake and a driver operated control for actuating the park brake. The driver operated control is preferably a manually operated control, such as a handbrake. The controller is arranged to cease inhibiting vehicle acceleration, at least partly, in response to the controller determining from the at least one brake system input signal that at least one of the park brake and the driver operated control is operated. This prevents, or at least significantly reduces the possibility of an SUA event occurring from a stationary condition, since the driver has to temporarily apply the park brake, in order to accelerate the vehicle.

In preferred embodiments, the plurality of operational conditions relate to at least one of: the stopping brake system; and the park brake system.

The controller is arranged to receive an input signal that is indicative of an operational condition of a vehicle door system.

The controller is arranged to cease inhibiting vehicle acceleration, at least partly, in response to the controller determining from the door system input signal that the vehicle door is closed. The controller is arranged to return acceleration control to the driver when the controller determines from the door system input signal that the vehicle door is closed. This is particularly useful for public transportation vehicles such as buses, mini-buses and coaches. Monitoring the operational status of the vehicle door helps to ensure that passengers are not at risk of falling out of the vehicle, before it moves off.

For non-public transport vehicles, such as lorries, refuse collection vehicles, cement mixers, etc, where the driver would typically have the door closed when driving, this feature is less useful. Therefore, in some embodiments, it is preferred not to receive input signals from the door system.

The vehicle door system includes at least one door control arranged to open and/or close at least one vehicle door. The controller is arranged to cease inhibiting vehicle acceleration, at least partly, in response to the controller determining from the door system input signal that the at least one door control is operated.

In preferred embodiments, the plurality of operational conditions relate to at least one of: the stopping brake system; the park brake system; and the door system. Preferably the plurality of operational conditions relate to at least two of: the stopping brake system; the park brake system; and the door system.

In preferred embodiments, the controller is arranged to determine from the actuation input signal that the vehicle is stationary; and inhibit vehicle acceleration, at least partly, in response to determining that the vehicle is stationary.

In some embodiments, the at least one actuation input signal includes a vehicle door system input signal, which is indicative of an operational condition of at least one vehicle door; and the controller is arranged to inhibit vehicle acceleration, at least partly, in response to determining that an operational condition of the vehicle door is met.

In some embodiments, the at least one actuation input signal includes a park brake system input signal, which is indicative of an operational condition of the park brake; and the controller is arranged to inhibit vehicle acceleration, at least partly, in response to determining that the park brake is engaged. The controller can determine that the vehicle is stationary, at least partly, when it determines that the park brake is engaged.

In some embodiments, the at least one actuation input signal includes an input signal indicative of vehicle road speed; and the controller is arranged to inhibit vehicle acceleration, at least partly, in response to determining that the vehicle road speed is less than or equal to a predetermined road speed value. For example, the controller can determine that the vehicle is stationary, at least partly, when it determines that the vehicle road speed is zero. The vehicle road speed input signal can be received, for example from at least one of a speed sensor and a positioning system, such as a Global Positioning System (GPS).

hi some embodiments, the at least one actuation input signal includes an impact detection sensor input signal; and the controller is arranged to inhibit vehicle acceleration, at least partly, in response to determining from the impact detection sensor input signal that the vehicle has collided with an object. This prevents vehicle acceleration after the vehicle has collided with an object, for example another vehicle, pedestrian and/or street furniture.

The controller is arranged to inhibit vehicle acceleration by inhibiting actuation of at least one vehicle control. The controller is arranged to inhibit operation of the vehicle control by at least one of: blocking normal control signals to the vehicle control; issuing a control signal to control operation of the vehicle control; issuing a control signal to a further control, wherein the further control inhibits operation of the vehicle control.

The at least one vehicle control is preferably arranged to control operation of a vehicle drive source. The vehicle drive source control is arranged to control the application of automotive power to a drive train, and thus control the rate at which the vehicle accelerates. The controller is arranged to inhibit acceleration of the vehicle by inhibiting operation of the drive source. The vehicle drive source can he any suitable type, for example a combustion engine (petrol or diesel); electric motor; and hybrid drive. The means of inhibiting operation of the vehicle drive source control is selected according to the way in which vehicle drive source control is normally actuated, for example electronically (so called drive-by-wire), electro-mechanically or mechanically. For example, the further control can be a mechanical device which is arranged to block movement of the vehicle control, thereby inhibiting vehicle acceleration.

In preferred embodiments the vehicle control includes at least one of an engine control unit (ECU); an electric motor controller; or an equivalent control for regulating the application of power for vehicles including other drive sources. In preferred embodiments the controller interacts with the ECU and/or electric motor controller to modify the output signal to the vehicle power source, thereby inhibiting vehicle acceleration.

For vehicles including a combustion engine, the ECU is typically arranged to control a throttle, and the controller is arranged to inhibit operation of the throttle.

The vehicle controller is arranged to receive at least one of the input signals and/or send control signals via a local network, such as a vehicle CAN bus and/or a hardwired network for non-CAN bus vehicles.

According to another aspect of the invention there is provided a vehicle including a control system according to any configuration described herein. The vehicle can be of any type, for example any road vehicle such as a bus, van, coach, car, lorry, mini-bus, heavy goods vehicle, cement mixer, and refuse collection vehicle.

The vehicle includes a brake system having at a least one sensor for detecting an operational condition of the braking system.

The brake system includes a stopping brake system and a sensor for sensing the actuation status of the stopping brake system. The stopping brake sensor is arranged to monitor the operational status of at least one of: a driver operated control, such as a brake pedal; a signal in a brake signal communications means, such as the pressure of hydraulic fluid in a hydraulic brake line, air pressure in a pneumatic line, tension in a brake wire, or an electrical signal in a brake-by-wire system; and/or (he position of a stopping brake component, such as brake pad or brake calliper.

The brake system includes a park brake system and a sensor for sensing the actuation status of the park brake system. The park brake system sensor is arranged to monitor the operational status of at least one of: a driver operated control, such as a handbrake; a signal in a brake signal communications means, such as the pressure of hydraulic fluid in a hydraulic brake line, air pressure in a pneumatic line, tension in a park brake wire or an electrical signal in a brake-by-wire system; and/or the position of a stopping brake component, such as brake pad or brake calliper.

The vehicle includes at least one door and a sensor for detecting the open-closed status of the at least one door.

The vehicle includes at least one of a vehicle road speed sensor and a positioning system such as a Global Positioning System.

The vehicle includes at a vehicle impact sensor.

The vehicle includes at an automatic transmission system. The invention is particularly suited to vehicles including automatic transmissions.

The vehicle includes a local network such as a CAN bus and/or a hardwired network for non-CAN bus vehicles, wherein the controller is connected to the local network and is arranged to receive at least one of the input signals from the local network and/or issue at least one control signal via the local network.

According to another aspect of the invention there is provided a method for controlling operation of a vehicle, said vehicle including a brake system and a control system including at least one controller; the method including the controller receiving an actuation input signal; the controller, in response to receiving the actuation input signal, inhibiting vehicle acceleration; the controller receiving at least one input signal that is indicative of an operational condition of the vehicle brake system; and the controller ceasing inhibiting vehicle acceleration in response to the controller detemtining from the brake system input signal(s) that at least one operational condition is met.

In preferred methods, the controller ceases inhibiting vehicle acceleration when a plurality of operational conditions are met.

The brake system includes a stopping brake system having a sensor, and including the controller receiving an input signal from the sensor that is indicative of the operational status of the stopping brake system, and the controller ceases inhibiting vehicle acceleration when it determines that the stopping brake is applied for a predetermined period of time.

The vehicle includes at brake system includes a park brake system and a sensor, and including the controller receiving an input signal from the sensor that is indicative of the operational status of a park brake system, and the controller ceases inhibiting vehicle acceleration when it determines that the park brake is disengaged.

The vehicle includes a door and a door sensor, and including the controller receiving an input signal from the door sensor that is indicative of the open-closed status of the door, and the controller ceases inhibiting vehicle acceleration when it determines that the door is 25 closed.

The vehicle includes a power source control which is arranged to control the application of automotive force to a drivctrain, and including the controller inhibiting acceleration of the vehicle by inhibiting operation of the power source control until the at least one operational condition is met.

The controller is arranged to cease inhibiting vehicle acceleration when a plurality of operational conditions are met in a predetermined order.

In sonic embodiments, the driver is required to undertake a specific sequence of actions each time the vehicle stops in order for acceleration control to be returned to the driver. For example, one possible sequence of actions is: 1) park brake engaged; 2) door closed (if the door is open); 3) stopping brake applied; and 4) park brake disengaged. This is particularly useful for public transport vehicles, which stop to enable passengers to embark/disembark. Another possible sequence is: 1) park brake engaged; 2) stopping brake applied; and 3) park brake disengaged. In some embodiments, the order in which the park brake is disengaged and the stopping brake applied is not critical. That is, in some embodiments, the stopping brake can be applied before, during or after the park brake is disengaged. The controlled sequence of actions significantly reduces the likelihood of an SUA occurring, when moving off from a stationary position.

According to another aspect of the invention there is provided a control system for a vehicle, said control system including a controller arranged to: receive an input signal from a park brake system; and inhibit vehicle acceleration in response to the controller determining from the park brake input signal that the park brake is engaged.

According to another aspect of the invention there is provided a control system for a vehicle, said control system including a controller arranged to: receive an input signal that is indicative of vehicle road speed; and inhibit vehicle acceleration in response to the controller determining from the input signal that the vehicle is stationary.

According to another aspect of the invention there is provided a control system for a vehicle, said control system including a controller arranged to: receive an input signal from an impact detection sensor; and inhibit vehicle acceleration in response to the controller determining from the sensor input signal that the vehicle has collided with an object. This prevents the vehicle from accelerating after a vehicle collision has occurred.

According to another aspect of the invention there is provided a control system for a vehicle, said control system including a controller arranged to: receive an input signal from a vehicle door system; and inhibit vehicle acceleration in response to the controller determining from the vehicle door input signal that a vehicle door operating condition is met. In sonic embodiments, the operating condition is at least one vehicle door is open. In some embodiments, the operating condition is at least one vehicle door is closed.

According to another aspect of the invention there is provided a control system for a vehicle, said control system including a controller an-anged to: receive input signal(s) from a stopping brake system; and cease inhibiting vehicle acceleration in response to the controller determining from the stopping brake input signals) that the stopping brake is applied. Advantageously the controller is arranged to cease inhibiting vehicle acceleration in response to the controller determining from the stopping brake input signal(s) that the stopping brake is applied for at least a predetermined period of time.

According to another aspect of the invention there is provided a control system for a vehicle, said control system including a controller Luranged to: receive input signal( s) from a park brake system; and cease inhibiting vehicle acceleration in response to the controller determining from the park brake input signal(s) that the park brake is disengaged.

According to another aspect of the invention there is provided a control system for a vehicle, said control system including a controller arranged to: determine that the vehicle is stationary; inhibit operation of a drive source control in response to determining that the vehicle is stationary; receive at least one input signal from a vehicle brake system; and cease inhibiting operation of the drive source control in response to the controller determining from the brake system input signal(s) that a brake system driver operated control is operated.

According to another aspect of the invention there is provided a control system for a vehicle, said control system including a controller arranged to: determine that the vehicle is stationary; inhibit operation of a drive source control in response to determining that the vehicle is stationary; and to cease inhibiting operation of the drive source control in response to the driver actuating at least one vehicle control, said vehicle control being a control other than an accelerator control.

According to another aspect of the invention there is provided a control system for a vehicle, said control system including a controller arranged to: inhibit vehicle acceleration in response to determining that the vehicle is stationary; receive at least one input signal that is indicative of an operational condition of at least one vehicle system; and to cease inhibiting vehicle acceleration in response to the controller determining from the at least one vehicle system input signal that the at least one operational condition is met.

An embodiment of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 is a schematic diagram of a vehicle in accordance with the invention; Figure 2 is a schematic diagram of a vehicle controller in accordance with the invention; and Figure 3 a schematic diagram of a control sequence used by the controller of Figure 2.

Figure 1 shows a schematic diagram of part of a vehicle 1 in accordance with the invention. The vehicle is a road vehicle, such as a bus, van, coach, car, lorry, mini-bus, heavy goods vehicle, cement mixer, and refuse collection vehicle. The vehicle 1 includes a brake system 3, a door system 5, a controller 7, wheels 9, engine 11, engine control unit (ECU) 13, an accelerator pedal 15, an automatic transmission system (not shown), and a local network 16 such as a CAN bus or a hardwired network.

The brake system 3 includes a stopping brake system and a park brake system. The stopping brake system is the normal means by which the driver slows the vehicle when 20 driving.

The stopping brake system includes a brake pedal 17. a sensor 19 arranged to monitor the operational position of the brake pedal 17 and brake units 21, which are each arranged to apply a brake load to their respective wheels 9 in response to the driver operating the brake pedal 17. By determining the position of the brake pedal 17, it is possible to determine the operational status of the stopping brake system. It will be appreciated by the skilled person that the operational status of the stopping brake system can be determined from other braking system components, such as by measuring pressure in a hydraulic brake line, monitoring electrical signals in a brake-by-wire system, or monitoring the operational position of another component such as a brake caliper or brake pad.

The sensor 19 is connected to the local network 16. The controller 7 receives input signals from the sensor 19 via the local network 16. The controller 7 is arranged to determine the operational status of the stopping brake system from the input signals received from that sensor 19.

The park brake system includes a handbrake 23, the brake units 21 and/or other brake units (not shown), and a sensor 25. The park brake system is used by the driver when a vehicle is stationary to maintain the parked position of the vehicle. The sensor 25 is arranged to monitor the position of the handbrake 23. The sensor 25 is connected to the local network 16. The controller 7 receives input signals from the sensor 25 via the local network 16. The controller 7 is arranged to determine the operational status of the park brake system from the input signals received from that sensor 25. By monitoring the operational position of the handbrake 23 it is possible for the controller 7 to determine the operational status of the park brake system. Of course it will be appreciated by the skilled person that it is possible to monitor other parts of the park brake system in order to determine the operational status of the power brake system, for example by monitoring tension in a brake wire, measuring pressure in a hydraulic brake line, monitoring electrical signals in a brakeby-wire system, or the operational position of a brake caliper or brake pad.

The controller 7 is able to determine, at least in part, from the park brake input signal if the vehicle is stationary.

The vehicle door system 5 includes a vehicle door 27, a door control 29 and a sensor 31. The door 27 is opened and closed by the driver operating the door control 29. The sensor 31 senses the open/closed condition of the door 27. The sensor 31 is connected to the local network 16. The controller 7 7 receives input signals from the sensor 31 via the local network 16. The controller 7 is able to determine the open/closed status of the door 27 from the input signals received from the sensor 31. It will of course be appreciated that the controller 7 can be arranged to monitor the switching status of door control 29 in order to determine the operational condition of the door system 5.

The controller 7 receives an input signal from a vehicle road speed sensor 35, via the local network 16. The vehicle road speed sensor 35 is typically the normal sensor used to supply a speed signal to the vehicle road speedometer. The controller 7 is arranged to determine, at least in part, from the vehicle road speed input signal when the vehicle is stationary.

The controller 7 receives an input signal from a collision impact sensor 37. The controller 7 is able to determine from that impact sensor input signal when the vehicle 1 has collided with an object such as another vehicle, wall, street furniture, etc. The controller 7 is connected to the ECU 13 via the local network 16. The ECU 13 is arranged to control operation of the engine 11. The ECU 13 controls the output of the engine 11 to a drive train (not shown) in response to a demand requested by the driver operating the accelerator pedal 15. The ECU 13 controls a throttle, which matches the engine output to the acceleration demand requested by the driver. The controller 7 is arranged to send control signals to the ECU 13 to inhibit vehicle acceleration in response to the initiation of a control protocol. The controller 7 is arranged to send control signals (or to stop sending control signals) to the ECU 13 to cease inhibiting vehicle acceleration in response to the controller determining from the input signals received that certain operational conditions have been met. The controller 7 is arranged to issue a control signal to the ECU 13 in order to inhibit vehicle acceleration, by modifying the normal demand signal applied to the ECU from the accelerator pedal 15. By interacting with the ECU 13 the controller 7 is able to prevent the engine 11 from opening the throttle thereby preventing the application of automotive power to the drive train.

The controller 7 is in the form of a microprocessor controller. The controller 7 is connected to the brake system 3, door system 5, ECU 13, speed sensor 35 and impact senor 37 via the local network 16 (this is illustrated diagrammatically as a series of connections in Figure 1).

The controller 7 is arranged to issue an output signal to at least one of a warning lamp and a buzzer 39, when the controller 7 determines from the input signals that at least one operational condition is not met. For example, the controller 7 is arranged to control the warning lamp and/or buzzer in response to detecting that the vehicle is stationary, from the speed input signal, and the handbrake 23 has not been engaged.

Optionally, the controller 7 can he provided with an override button 39. This enables the driver to override the controller 7 by depressing the button for a predetermined period of time, for example 5 seconds. Operating the override button restores acceleration control to the driver irrespective of whether the operational conditions have been met.

One possible control protocol for temporarily inhibiting vehicle acceleration, by temporarily removing acceleration control from the driver, will now be described with reference to Figure 3: 1. The controller 7 determines 100 from the speed sensor 35 input signal that the vehicle road speed is zero and/or the park brake sensor 25 input signal that the park brake is engaged; 2. In response to this, the controller 7 issues an output signal 104 to the ECU 13 to inhibit vehicle acceleration 106, which temporarily prevents the driver from accelerating the vehicle; 3. The controller 7 monitors the input signals received from the stopping brake sensor 19, the park brake sensor 25 and, optionally, the door sensor 31; 4. The controller 7 returns acceleration control to the driver when the controller 7 determines from the input signals that: the driver has pressed the brake pedal 17 for at least a predetermined period of time 110, such as 2 seconds; the park brake is disengaged; and, optionally, the door 27 is closed 108; 5. The controller returns acceleration control to the driver 112 by the controller 7 sending a control signal to the ECU 13, or by the controller 7 ceasing to send inhibit control signals to the ECU 13.

The control protocol prevents the driver from causing a SUA event, since it is necessary for the driver to perform at least one action before he can drive away from the stationary position.

If the controller 7 detects that the handbrake 23 has not been engaged when the vehicle has been stationary for a predetermined period of time, say 5 seconds, the controller 7 outputs a signal to the warning lamp and/or buzzer 39 to prompt the driver to apply the handbrake 23.

Optionally the controller 7 can be programmed to inhibit vehicle acceleration if it determines from the vehicle road speed sensor that the vehicle is stationary for a second predetermined period of time without the driver having engaged the handbrake. For example, if the vehicle is stationary for around 10 to 20 seconds, and preferably around 15 seconds.

If the controller 7 determines from the impact sensor 37 that the vehicle 1 has collided with an object, the controller 7 issues a control signal to the ECU 13 to inhibit vehicle acceleration. This prevents a driver from initiating a sudden unintended acceleration event in response to colliding with an object.

Although the present invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Furthermore, it will he apparent to the skilled person that modifications can be made to the above embodiment that fall within the scope of the invention.

For example, while the above protocol indicates the required conditions (park brake engaged; door closed; stopping brake applied; park brake disengaged) to return acceleration control to the driver. There is some flexibility in the order in which the actions can he performed. In some embodiments, the driver can he required to perform actions in a particular sequence in order for acceleration control to be returned. For example, one possible sequence is 1) park brake engaged; 2) optionally, door closed; 3) slopping brake applied; and 4) park brake disengaged; in that order. This is particularly useful for public transport vehicles, which stop to enable passengers to embark/disembark. Another possible sequence is: 1) park brake engaged; 2) stopping brake applied; and 3) park brake disengaged; in that order. In some embodiments, the order in which the park brake is disengaged and the stopping brake applied does not matter. That is, the stopping brake can be applied before, during or after the park brake is disengaged. The controlled sequence of actions significantly reduces the likelihood of an SUA occurring, when moving off from a stop.

The inventors have determined that the most significant of the operational conditions to be met prior to returning acceleration control to the driver to prevent SUAs occurring, is the requirement to actuate the stopping brake, by applying the brake pedal 17. Thus, in a simplified protocol, only a single operational condition is required to be met before the controller 7 restores acceleration control to the drive, which is that the driver actuates the stopping brake system by applying the brake pedal 17, for example for a predetermined period of time.

In other protocols it is preferred that at least two operational conditions are required to be met before the controller 7 restores acceleration control to the drive. For example, in preferred protocols at least two of the following operational conditions are required to be met for acceleration control to be returned to the driver: handbrake engaged; handbrake disengaged; door closed; and brake pedal applied for a predetermined period of time.

While the invention is particularly suited to vehicles having an automatic transmission system, the invention is also applicable to vehicles that don't include an automatic transmission system, such as vehicles including a semi-automatic transmission system or a manual transmission system.

The vehicle may include a drive source other than an engine 11. For example, the vehicle can be an electric vehicle, which includes an electric motor and an electric motor control instead of an ECU. The vehicle may he a hybrid vehicle, which includes an engine having and ECU and an electric motor having an electric motor controller. It is possible that other drive sources may be used, which have some other kind of controller. In each case, the controller 7 is arranged to interact with drive source controller in order to selectively inhibit vehicle acceleration.

The controller 7 can be retro-fitted to a vehicle as a separate microprocessor controller. Alternatively, the controller can be part of an existing controller or control system. For example, the ECU can he programmed to perform the controller function.

Claims

-1 8-Claims 1 A control system for a vehicle, said control system including a controller arranged to: receive at least one actuation input signal; inhibit vehicle acceleration in response to receiving the actuation input signal(s); receive at least one input signal that is indicative of an operational condition of a vehicle brake system; and cease inhibiting vehicle acceleration in response to the controller determining from the brake system input signals) that at least one brake system operational condition is met.
2. A control system according to claim 1, wherein the brake system includes at least one driver operated control, and the controller is arranged to cease inhibiting vehicle acceleration, at least partly, in response to the controller determining from the at least one brake system input signal that the driver operated control is operated.
3. A control system according to claim 1 or 2, wherein the brake system includes a plurality of driver operated controls, and the controller is arranged to cease inhibiting vehicle acceleration, at least partly, in response to the controller determining from the brake system input signals that each driver operated control is operated.
4. A control system according to any one of the preceding claims, wherein the vehicle brake system includes a stopping brake system and the controller is arranged to receive an input signal that is indicative of an operational condition of the stopping brake system.
5. A control system according to claim 4, wherein the controller is arranged to determine from the stopping brake input signal the actuation status of the stopping brake system.
6. A control system according to claim 4 or 5, wherein the controller is arranged to cease inhibiting vehicle acceleration, at least partly, in response to the controller determining from the input signal that the stopping brake system is applied.
7. A control system according to any one of claims 4 to 6, wherein the stopping brake system includes a stopping brake and a driver operated control for actuating the stopping brake, and the controller is arranged to cease inhibiting vehicle acceleration, at least partly, in response to the controller determining from the brake system input signal(s) that at least one of the stopping brake and the driver operated control is applied.
8. A control system according to any one of claims 4 to 7, wherein controller is arranged to cease inhibiting vehicle acceleration, at least partly, in response to the controller determining from the input signal that the stopping brake system is applied for a period of time that is greater than or equal to a predetermined period of time.
9. A control system according to any one of the preceding claims, wherein the vehicle brake system includes a park brake system and the controller is arranged to receive an input signal that is indicative of an operational condition of the park brake system.
10. A control system according to claim 9, wherein the controller is arranged to determine from the input signal the actuation status of the park brake system.
11. A control system according to claim 9 or 10, wherein the controller is arranged to cease inhibiting vehicle acceleration, at least partly, in response to the controller determining from the park brake input signal that the park brake system is disengaged.
12. A control system according to any one of claims 9 to 11, wherein the park brake system includes a park brake and a driver operated control for actuating the park brake, and the controller is arranged to cease inhibiting vehicle acceleration, at least partly, in response to the controller determining from the at least one brake system input signal that at least one of the park brake and the driver operated control is disengaged.
13. A control system according to any one of the preceding claims, wherein the controller is arranged to receive an input signal that is indicative of an operational condition of a vehicle door system.
14. A control system according to claim 13, wherein the controller is arranged to cease inhibiting vehicle acceleration, at least partly, in response to the controller determining from the door system input signal that the vehicle door is closed.
15. A control system according to claim 13 or 14, wherein the vehicle door system includes a driver operated control arranged to open and/or close the vehicle door, and the controller is arranged to cease inhibiting vehicle acceleration, at least partly, in response to the controller determining from the door system input signal that the driver operator control is operated.
16. A control system according to any one of the preceding claims, wherein the controller is arranged to determine from the actuation input signal that the vehicle is stationary; and inhibit vehicle acceleration, at least partly, in response to determining that the vehicle is stationary.
17. A control system according to any one of the preceding claims, wherein the at least one actuation input signal includes a vehicle door system input signal, which is indicative of an operational condition of at least one vehicle door; and the controller is arranged to inhibit vehicle acceleration, at least partly, in response to determining that an operational condition of the vehicle door is met.
18. A control system according to any one of the preceding claims, wherein the at least one actuation input signal includes a park brake system input signal, which is indicative of an operational condition of the park brake; and the controller is arranged to inhibit vehicle acceleration, at least partly, in response to determining that the park brake is engaged.
19. A control system according to any one of the preceding claims, wherein the at least one actuation input signal includes an input signal indicative of vehicle road speed; and the controller is arranged to inhibit vehicle acceleration, at least partly, in response to determining that the vehicle road speed is less than or equal to a predetermined road speed value.
20. A control system according to any one of the preceding claims, wherein the at least one actuation input signal includes an impact detection sensor input signal; and the controller is arranged to inhibit vehicle acceleration, at least partly, in response to determining from the impact sensor input signal that the vehicle has collided with an object.
21. A control system according to any one of the preceding claims, wherein the controller is arranged to inhibit vehicle acceleration by interacting with at least one vehicle control.
22. A control system according to claim 21, wherein the controller is arranged to interact with the vehicle control by means of at least one of: blocking normal control signals to the vehicle control; issuing a control signal to control operation of the vehicle control; issuing a control signal to a further control, wherein the further control inhibits operation of the vehicle control.
23. A control system according to claim 21 or 22, wherein the at least one vehicle control is arranged to control operation of a vehicle drive source.
24. A control system according to any one of claims 21 to 23, wherein the vehicle control includes at least one of: an engine control unit (ECU); and an electric motor controller.
25. A control system according to any one of the preceding claims, wherein the vehicle controller is arranged to receive at least one of the input signals via a vehicle local network.
26. A vehicle including a control system according to any one of the preceding claims.
27. A vehicle according to claim 26, including a brake system having at a least one sensor for detecting an operational condition of the braking system.
28. A vehicle according to claim 27, wherein brake system includes a stopping brake system having at least one sensor for sensing the actuation status of the stopping brake system.
29. A vehicle according to claim 28, wherein the stopping brake sensor is arranged to monitor the operational status of at least one of: a driver operated control, such as a brake pedal; a signal in a brake signal communications means, such as the pressure of hydraulic fluid in a hydraulic brake line, air pressure in a pneumatic line, tension in a brake wire, or an electrical signal in a brake-by-wire system; and/or the position of a stopping brake component, such as brake pad or brake calliper.
30. A vehicle according to any one of claims 27 to 29, wherein brake system includes a park brake system having at least one sensor for sensing the actuation status of the park brake system.
31 A vehicle according to claim 30, wherein the park brake system sensor is arranged to monitor the operational status of at least one of: a driver operated control, such as a handbrake; a signal in a brake signal communications means, such as the pressure of hydraulic fluid in a hydraulic brake line, air pressure in a pneumatic line, tension in a brake wire, or an electrical signal in a brake-by-wire system; and/or the position of a stopping brake component, such as brake pad or brake calliper.
32. A vehicle according to any one of claims 26 to 31, including a door system having at least one door and at least one sensor for detecting the open-closed status of the at leas( one door.
33. A vehicle according to any one of claims 26 to 32, including at least one of a vehicle road speed sensor and a positioning system.
34. A vehicle according to any one of claims 26 to 33, including a vehicle impact sensor.
35. A vehicle according to any one of claims 26 to 34, including an automatic transmission system.
36. A vehicle according to any one of claims 26 to 35, including a local network, wherein the controller is connected to the local network and is arranged to receive at least one of the input signals via the local network and/or issue at least one control signal via the local network.
37. A method for controlling a vehicle, said vehicle including a brake system and a control system including at least one controller; the method including: the controller receiving an actuation input signal; the controller, in response to receiving the actuation input signal, inhibiting vehicle acceleration; the controller receiving at least one input signal that is indicative of an operational condition of the vehicle brake system; and the controller ceasing inhibiting vehicle acceleration in response to the controller determining from the brake system input signal(s) that at least one operational condition is met.
38. A method according to claim 37, wherein the brake system includes a stopping brake system having a sensor, and including the controller receiving an input signal from the sensor that is indicative of the operational status of die stopping brake system, and the controller ceases inhibiting vehicle acceleration, at least partly, when it determines that the stopping brake is applied for a predetermined period of time.
39. A method according to claim 37 or 38, wherein the brake system includes a park brake system and a sensor, and including the controller receiving an input signal from the sensor that is indicative of the operational status of a park brake system, and the controller ceases inhibiting vehicle acceleration, at least partly, when it determines that the park brake is disengaged.
40. A method according to any one of claims 37 to 39, wherein the vehicle includes a door and a door sensor, and including the controller receiving an input signal from the door sensor that is indicative of the open-closed status of the door, and the controller ceases inhibiting vehicle acceleration, at least partly, when it determines that the door is closed.
41. A method according to any one of claims 37 to 40, wherein the vehicle includes a power source control which is arranged to control the application of automotive force to a drivetrain, and including the controller inhibiting acceleration of the vehicle by inhibiting operation of the power source control until the at least one operational condition is met.
42. A method according to any one of claims 37 to 41, wherein the controller is arranged to cease inhibiting vehicle acceleration when a plurality of operational conditions are met in a predetermined order.
43. A method according to any one of claims 37 to 42, wherein the controller is arranged to determine that the vehicle is stationary from at least one of a: speed sensor input signal and park brake sensor input signal.