AU2011226993A1

AU2011226993A1 - Emergency Braking System

Info

Publication number: AU2011226993A1
Application number: AU2011226993A
Authority: AU
Inventors: Erland George Olofsson
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-06-29
Filing date: 2011-10-03
Publication date: 2013-01-17
Anticipated expiration: 2031-10-03
Also published as: AU2018282491B1; AU2011226993B2

Abstract

- j I An accelerator braking system for a vehicle; said braking system reactive to forces applied to an accelerator pedal of said vehicle; said system characterized by a 5 transmission to a control module of data corresponding to said forces applied to said accelerator pedal wherein braking force is gradually increased and decreased by operation of the accelerator pedal. In a preferred form, the braking system is reactive to forces applied to a 10 secondary reaction surface of an accelerator pedal of said vehicle; said system characterized by a transmission to a control module of force data or angle data wherein braking force is gradually increased and decreased by operation of the accelerator pedal; said system arranged to switch to an 15 emergency braking mode on sensing rapid movement of said accelerator pedal in a decelerating direction. $s e a e00 \n0 E! Ei E! C) ~ 0E

Description

P100/009 AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION Invention Title: EMERGENCY BRAKING SYSTEM The invention is described in the following statement together with the best method of performing it known to us: Our Ref: 112030 - 2 EMERGENCY BRAKING SYSTEM The present invention relates to control systems for motor vehicles and, more particularly to the interaction of acceleration and braking of a vehicle and even more 5 particularly to a modular electronic device for implementing same. BACKGROUND It is well known that the distance required to bring a 10 moving vehicle to a standstill from the instant a driver perceives a potentially hazardous situation to the vehicle coming to rest, is a combination of the reaction distance and the braking distance. The reaction distance is that distance covered during 15 the delay between which the mind of the driver perceives the situation and decides to act, to the actual activating of the vehicles braking system. The braking distance is that distance actually required to bring the vehicle to a standstill from the speed at which it was travelling under 20 the application of the optimum braking force. Both the reaction distance and the braking distance are clearly functions of the initial speed of the vehicle, while the braking distance is additionally affected by road and weather conditions as well as the efficiency of the 25 braking system.

- 3 Improvements in braking systems have significantly reduced the braking distance in emergency situations, while the reaction distance has tended to remain relatively stable. A disadvantage in conventional vehicle control 5 systems in an emergency situation is that the reaction distance is partly made up of the time taken to physically lift the driver's foot from the accelerator pedal, transfer it to the brake pedal and depress that pedal. Conventional control systems also are inconvenient in 10 non-emergency braking situations. For example in "stop start" traffic situations, the need to repeatedly transfer the driver's foot from one pedal to the other can become very tiring. The applicant's earlier filed International Patent 15 Application number PCT/AU01/00582 and prior art US Patent 3082851 to Sheriff disclose substantially mechanical arrangements. However such arrangements are prone to failure and are difficult to calibrate. They can also be difficult to retrofit. They can also be difficult to 20 customise "on the fly" to suit the preferences of the individual driver. It is an object of the present invention to address or ameliorate some of the above disadvantages. 25 -4 Notes 1. The term "comprising" (and grammatical variations thereof) is used in this specification in the inclusive sense of "having" or "including", and not in 5 the exclusive sense of "consisting only of". 2. The above discussion of the prior art in the Background of the invention, is not an admission that any information discussed therein is citable prior art or part of the common general knowledge of persons 10 skilled in the art in any country. DEFINITIONS In this specification, the following terms are to have the meanings as defined here: 15 "Secondary reaction surface" means a surface interposed between at least a portion of the accelerator pedal of a vehicle and another surface against which it reacts. In one instance the surface against which the secondary reaction 20 surface reacts may be that of a foot applied to the accelerator pedal. In other instances, other surfaces can be utilised.

- 5 BRIEF DESCRIPTION OF INVENTION Accordingly, in one broad form of the invention, there is provided an emergency accelerator braking system for a vehicle; said vehicle including and accelerator pedal and a 5 separate brake pedal for control of said vehicle; said braking system reactive to position and movement of said accelerator pedal of said vehicle; said system characterized by transmission to a control module of control pedal behaviour data comprising at least one of 10 force data representative of force applied by a driver to said accelerator pedal and position data representative of the relative position of said accelerator pedal, and wherein braking force is gradually increased and decreased by operation of the accelerator pedal over at least a 15 portion of travel of said accelerator pedal; said system arranged to switch to an emergency braking mode on sensing rapid movement of said accelerator pedal above a predetermined threshold value in a decelerating direction. Preferably, said predetermined threshold value is measured 20 as rate of angular movement of said accelerator pedal about a pivot point of said pedal. Preferably, said predetermined threshold value is measured as rate of movement of at least a portion of said accelerator pedal about a pivot point of said pedal.

- 6 Preferably, said portion of said accelerator pedal is a top portion of said accelerator pedal, Preferably, said pivot point is located at or near a base portion of said accelerator pedal, 5 Preferably, said predetermined threshold value is a multiple of the highest value achieved in normal operation of said accelerator pedal. Preferably, said multiple is 2. Preferably, said multiple is 10. 10 Preferably, said accelerator pedal operates in zone mode (as defined in this specification) and wherein said emergency braking mode operates on sensing rapid movement of said accelerator pedal from any position including acceleration zone, braking zone or neutral zone. 15 Preferably, said system operates with zone mode in operation (on-line mode). Preferably, said system operates according to the diagram of Fig 7 in on-line mode. In an alternative preferred form, said system operates with 20 zone mode switched off (off-line mode).

- 7 In an alternative preferred form, said system of claim 9 operating according to the diagram of fig 7 in off-line mode. 5 In another broad form of the invention, there is provided an accelerator braking system as described above for said vehicle operable in zone mode; said braking system reactive to forces applied to a secondary reaction surface of said accelerator pedal of said vehicle. 10 Preferably, said control module includes a servomotor acting on said braking system. Preferably, said servomotor acts on said separate brake pedal of said braking system. Preferably, said secondary reaction surface comprises a 15 hinged auxiliary pedal attached to said accelerator pedal; said hinged auxiliary pedal arranged for movement from a first deactivated state to a second fully activated state by pressure applied by a foot of a driver. Preferably, aid hinged auxiliary pedal includes a sensor in 20 electronic communication with said control module. Preferably, in said fully activated state, additional pressure applied by said foot of said driver is transferred - 8 to said accelerator pedal so as to urge said accelerator pedal into an activated position. Preferably, pressure applied by said foot of a driver to urge said secondary reaction surface from said deactivated 5 state to said fully activated state is less than pressure required to urge said accelerator pedal from a deactivated state into a said activated position. Preferably, transition from said fully activated state of said secondary reaction surface to a said activated 10 position of said accelerator pedal includes a neutral feel zone perceptible to said driver. Preferably, an indicator light mounted in view of a said driver of said vehicle is activated when pressure applied to said accelerator pedal is in said neutral feel zone. 15 Preferably, a transition from a said inactive state to a said fully activated state of said secondary reaction surface, is accompanied by a transition of said braking system from at least a percentage of full braking force to a zero braking force. 20 Preferably, said accelerator braking system is enabled in zone mode by a suitably mounted enable switch within reach of a driver of said vehicle.

- 9 Preferably, said enable switch is illuminated when and only when the system is enabled in zone mode. Preferably, said system includes an additional illuminated sign which includes indicia which communicate to the driver 5 that the system is operating in zone mode. Preferably, said brake pedal is provided with a secondary reaction surface; said secondary reaction surface comprising a pressure sensitive pad incorporating a disable switch, whereby pressure applied to said secondary reaction 10 surface operates said switch to deactivate said control module. Preferably, a range of said braking force between said zero braking force and said at least a percentage of full braking force (up to 100% of braking force) is adjustable 15 from a dial control mounted within reach of a said driver of said vehicle. Preferably, the rate of response of said control module to said transmission of force data between said zero braking force and said at least a percentage of full braking force 20 is adjustable from a dial control mounted within reach of a said driver of said vehicle. Preferably, said system is turned off when a foot is placed on said brake pedal.

- 10 Preferably, an "on" switch is available to switch the system on. Preferably, said switch is illuminated when said system is on. 5 Preferably, a "coasting light" is illuminated when said accelerator pedal is in said neutral feel zone. In a further broad form of the invention, there is provided a method of reducing reaction time between a 10 perceived need to brake a vehicle and application of the brakes of said vehicle; said method including the steps of: providing a secondary reaction surface to an accelerator pedal of a said vehicle, electronically linking said secondary reaction surface 15 with a control module acting on a brake pedal of said vehicle; said system arranged to switch to an emergency braking mode on sensing rapid movement of said accelerator pedal in a decelerating direction. 20 Preferably, said secondary reaction surface is operable between an inactivated state and a fully activated state.

- 11 Preferably, said control module activates said brakes of said vehicle between at least a percentage of full braking force and zero braking force, as force applied to said secondary reaction force varies between zero and a maximum. 5 In a further broad form of the invention, there is provided a method of braking a vehicle by means of interaction between a secondary reaction surface applied to an accelerator pedal, and a control module; said control 10 module acting on a brake pedal of said vehicle; said method including the steps of: arranging said secondary reaction surface to respond to pressure from a driver of said vehicle between a first deactivated state and a fully activated state. 15 arranging said control module to act on a brake pedal of said vehicle, between applying at least a percentage of full braking force and a zero braking force as said secondary reaction surface responds between said first deactivated state and said fully 20 activated state; said system arranged to switch to an emergency braking mode on sensing rapid movement of said accelerator pedal in a decelerating direction.

- 12 In a further broad form of the invention, there is provided a method of urging a vehicle into motion by means of operation of an accelerator pedal of said vehicle; said method including the steps of: 5 applying a first increasing pressure to a secondary reaction surface of said accelerator pedal, increasing said first increasing pressure to a maximum reaction point of said reaction surface so as to disengage a braking system of said vehicle, 10 applying a second increasing pressure to said secondary reaction surface so as to urge said accelerator pedal into a depressed state, whereby the state of said vehicle is changed from a braked standstill to a state of motion; said system arranged to 15 switch to an emergency braking mode on sensing rapid movement of said accelerator pedal in a decelerating direction, In a further broad form of the invention, there is 20 provided a method of bringing a vehicle to a standstill by means of operation of an accelerator pedal of said vehicle; said method including the steps of: - 13 applying a first decreasing pressure to a secondary reaction surface of said accelerator pedal in a depressed state, decreasing said first decreasing pressure to a point 5 at which said accelerator pedal is fully retracted from said depressed state, applying a second decreasing pressure to said secondary reaction surface, decreasing said second decreasing pressure to a point 10 where there is no pressure applied to said secondary reactions surface, whereby the state of said vehicle is changed from one in motion to a state of braked standstill; said system arranged to switch to an emergency braking mode on sensing 15 rapid movement of said accelerator pedal in a decelerating direction. In a further broad form of the invention, there is provided a method of control of a vehicle; said vehicle 20 having an accelerator pedal and a separate brake pedal; said method comprising communicating accelerator pedal position data to a controller; on the basis of position of said accelerator pedal as determined by said accelerator - 14 position data; causing a signal to be sent from said controller to a brake controller as a function of said accelerator pedal position data thereby to operate said brake pedal; said system arranged to switch to an emergency 5 braking mode on sensing rapid movement of said accelerator pedal in a decelerating direction. In a further broad form of the invention, there is provided a method of urging a vehicle into motion by means 10 of operation of an accelerator pedal of said vehicle; said method including the steps of: applying a first increasing pressure to said accelerator pedal, increasing said first increasing pressure to a maximum 15 reaction point so as to disengage a braking system of said vehicle, applying a second increasing pressure to said accelerator pedal so as to urge said accelerator pedal into a depressed state, 20 whereby the state of said vehicle is changed from a braked standstill to a state of motion; said system arranged to switch to an emergency braking mode on sensing rapid - 15 movement of said accelerator pedal in a decelerating direction. In a further broad form of the invention, there is 5 provided a method of bringing a vehicle to a standstill by means of operation of an accelerator pedal of said vehicle; said method including the steps of: applying a first decreasing pressure to said accelerator pedal in a depressed state, 10 decreasing said first decreasing pressure to a point at which said accelerator pedal is fully retracted from said depressed state, applying a second decreasing pressure to said secondary reaction surface, 15 decreasing said second decreasing pressure to a point where there is no pressure applied to said secondary reactions surface, whereby the state of said vehicle is changed from one in motion to a state of braked standstill; said system 20 arranged to switch to an emergency braking mode on sensing rapid movement of said accelerator pedal in a decelerating direction.

- 16 In a further broad form of the invention, there is provided an accelerator braking system for a vehicle; said braking system reactive to forces applied to an accelerator pedal of said vehicle; said system characterized by a 5 transmission to a control module of data corresponding to said forces applied to said accelerator pedal wherein braking force is gradually increased and decreased by operation of the accelerator pedal; said system arranged to switch to an emergency braking mode on sensing rapid 10 movement of said accelerator pedal in a decelerating direction. Preferably, said braking force is a function of the forces applied to said accelerator pedal at least over a portion of the range of forces applied to said accelerator pedal. 15 In a further broad form of the invention, there is provided an accelerator braking system for a vehicle; said braking system reactive to forces applied to an accelerator pedal of said vehicle; said system characterized by a 20 transmission to a control module of force data or angle data wherein braking force is gradually increased and decreased by operation of the accelerator pedal; said system arranged to switch to an emergency braking mode on - 17 sensing rapid movement of said accelerator pedal in a decelerating direction. Preferably, said braking force is applied is a function of the forces applied to said accelerator pedal at least over 5 a portion of the range of forces applied to said accelerator pedal. Preferably, force is applied via a secondary reaction surface associated with said accelerator pedal. Preferably, said secondary reaction surface is interposed 10 between the foot of an operator and said accelerator pedal. Preferably, said secondary reaction surface is interposed between said accelerator pedal and an actuator surface. Preferably, said system further includes an accelerator pedal transducer associated with said accelerator pedal and 15 wherein data is transmitted from said transducer to said control module, Preferably, said system includes a brake pedal transducer associated with said a brake pedal of said vehicle and wherein data is transmitted from said brake pedal 20 transducer to said control module. Preferably, said control module comprises an engine control module of said vehicle; said engine control module - 18 controlling operation of the engine and related components of said vehicle. Preferably, said control module includes a servomotor acting on said braking system. 5 Preferably, said servomotor acts on a brake pedal of said braking system. Preferably, said servomotor is connected to a portion of a pedal arm of said brake pedal by means of a flexible coupling. 10 Preferably, said secondary reaction surface comprises a pressure sensitive mat covering at least a portion of said accelerator pedal; said pressure sensitive mat reactive to pressure applied by a foot of a driver between a first deactivated state and a second fully activated state of 15 said pressure sensitive mat. Preferably, said pressure sensitive mat includes a load cell in electronic communication with said control module. Preferably, said secondary reaction surface comprises a hinged auxiliary pedal attached to said accelerator pedal; 20 said hinged auxiliary pedal arranged for movement from a first deactivate state to a second fully activated state by pressure applied by a foot of a driver.

- 19 Preferably, said hinged auxiliary pedal includes a sensor in electronic communication with said control module. Preferably, said fully activated state, additional pressure applied by said foot of said driver is transferred to said 5 accelerator pedal so as to urge said accelerator pedal into an activated position. Preferably, pressure applied by said foot of a driver to urge said secondary reaction surface from said deactivated state to said fully activated state is less than pressure 10 required to urge said accelerator pedal from a deactivated state into a said activated position. Preferably, transition from said fully activated state of said secondary reaction surface to a said activated position of said accelerator pedal includes a neutral feel 15 zone perceptible to said driver. Preferably, an indicator light mounted in view of a said driver of said vehicle is activated when pressure applied to said accelerator pedal is in said neutral feel zone. Preferably, a transition from a said inactive state to a 20 said fully activated state of said secondary reaction surface is accompanied by a transition of said braking system from at least a percentage of full braking force to a zero braking force.

- 20 Preferably, said accelerator braking system is enabled by a suitably mounted enable switch within reach of a driver of said vehicle. Preferably, said enable switch is illuminated when and only 5 when the system is enabled. Preferably, said brake pedal is provided with a secondary reaction surface; said secondary reaction surface comprising a pressure sensitive pad incorporating a disable switch, whereby pressure applied to said secondary reaction 10 surface operates said switch to deactivate said control module. Preferably, a range of said braking force between said zero braking force and said at least a percentage of full braking force (up to 100% of braking force) is adjustable 15 from a dial control mounted within reach of a said driver of said vehicle. Preferably, the rate of response of said control module to said transmission of force data between said zero braking force and said at least a percentage of full braking force 20 is adjustable from a dial control mounted within reach of a said driver of said vehicle. Preferably, said system is turned off when a foot is placed on said brake pedal.

- 21 Preferably, an "on" switch is available to switch the system on. Preferably, said switch is illuminated when said system is on. 5 Preferably, a "coasting light" is illuminated when said accelerator pedal is in said neutral feel zone, Preferably, said emergency braking mode operates on sensing rapid movement of said accelerator pedal from any position including acceleration zone, braking zone or neutral zone. 10 Preferably, said system operates according to the diagram of fig 7 in on-line mode. Preferably, said system operates according to the diagram of fig 7 in off-line mode.

- 22 BRIEF DESCRIPTION OF DRAWINGS Embodiments of the present invention will now be described with reference to the accompanying drawings wherein: 5 Figure 1 (Prior Art) is an illustration of the two components, reaction distance and braking distance at various speeds which determine the overall distance required to bring a vehicle to a standstill from a first perceived need by a driver to do so, 10 Figure 2 comprises disclosure of an accelerator pedal with braking action (zone system)from applicant's earlier filed International Patent Application no PCT/AU01/00582 illustrating zones of preferred braking characteristics (zone mode) to be imparted as part of accelerator pedal 15 operation; the accelerator pedal in this instance not including a secondary reaction surface; Figure 3 is a general schematic of the accelerator and brake pedal controls of a vehicle fitted with the accelerator brake system in accordance with a preferred 20 embodiment of the present invention, Figure 4 is a schematic of a secondary reactive surface attached to an accelerator pedal according to a further preferred embodiment of the accelerator brake system of the invention, 25 Fig 5A is a schematic of a secondary reactive surface attached to an accelerator pedal according to a further - 23 preferred embodiment of the accelerator brake system of the invention and Fig 5B is a schematic of a secondary reactive surface attached to an accelerator pedal according to a further 5 preferred embodiment of the accelerator brake system of the invention Figure 6 is a brake pedal module, in accordance with a further preferred embodiment of the present invention, Figure 7 is a graph representing a non limiting 10 example of the interaction of the accelerator pedal, brake pedal and braking force of the accelerator brake system of Figures 3 to 6 operable either in zone mode or emergency braking mode; Figure 8 is a lay out of an installation of at least a 15 preferred embodiment of the present invention in the cabin of a vehicle. Figure 9 is a block diagram of' an electronic implementation of the modular arrangement of figure 8. Fig 10 is a block diagram of a "factory fit" 20 embodiment of the electronic implementation of the modular arrangement of figure 8. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS With reference to Figures 2 and 3, the controls of a 25 typical motor vehicle include an accelerator pedal 10 and a brake pedal 12. Although a vehicle equipped with a manually - 24 operated gear train may be additionally equipped with a clutch pedal, the present invention is concerned only with the two pedals, accelerator pedal 10 and brake pedal 12. In practise embodiments of the present invention are 5 suited to conventional automatic transmission equipped vehicles which have only an accelerator pedal and a brake pedal and do not have a third clutch pedal to assist changing gears. The vehicles may include cars, trucks and buses. 10 Embodiments to be described below describe some specific mechanisms which can be used to implement the emergency braking arrangement which, in broad principle, relies upon detecting a quicker-than-usual movement of the accelerator pedal in a deceleration direction, thereby to 15 indicate that the driver wishes the vehicle to decelerate more rapidly than usual, as, for example, in an emergency braking situation where an obstacle has appeared unexpectedly in front of the driver's vehicle. Embodiments of the emergency braking system may 20 operate in conjunction with an improved accelerator pedal having braking action included within its function, as has been described in PCT/AU01/000582 to the same applicant. Other embodiments of the emergency braking function can be achieved without enablement of the system of the improved 25 accelerator pedal with braking action. In preferred forms, - 25 however, the same equipment as will be described below can be utilised to enable the emergency braking system. At its most fundamental embodimments of the emergeny braking system can be implemented on the pedal arrangement 5 of Fig 2. As shown in Figure 3, the brake pedal 12 according to embodiments of the invention, is provided with a control module 14, the function of which will be explained in more detail below. As seen in Figures 3 to 6, the accelerator 10 pedal 10 in some embodiments is provided with a secondary reaction surface 16. Secondary reaction surface 16 in a first preferred embodiment shown in Figure 4, comprises an auxiliary pedal 18, attached to a standard accelerator pedal 20 at a pivot 15 point comprising a hinge 21, and covers at least a portion of the accelerator pedal 20. In this instance, the auxiliary pedal 18 is arranged so it can be depressed against a spring 24 a certain amount relative to the surface 22 of accelerator pedal 20, without inducing 20 movement in accelerator pedal 20. When pressure is applied by the foot of a driver (not shown) past this point, the pressure applied is transmitted to the accelerator pedal 20, causing it to depress and urge the vehicle into motion in the usual way. 25 Auxiliary pedal 18 is thus arranged to move between a first deactivated state shown in Figure 4, (when there is a - 26 maximum possible movement between the auxiliary pedal 18 and the surface 22 of pedal 20), and the fully activated state at the point where further application of pressure will induce movement in accelerator pedal 20. This movement 5 between the deactivated state and the fully activated state is monitored by a sensor in this instance implemented in the form of a potentiometer 24 and relayed by lead 26 to control module 14 as force data. 10 Alternative arrangements for secondary reaction surface With reference to figs 5A and 5B, there are illustrated alternative arrangements wherein the secondary reaction surface takes the form of a guide arm mechanically 15 associated with a pivot which operates a sensor 150 preferably in the form of an angle transducer. With reference to fig 5A, operation is such that depression of accelerator pedal 20 causes a top portion 151 20 of accelerator pedal 20 to press against a secondary reaction surface in the form of pivot arm extension surface 152 thereby to cause rotation of sensor arm 153 about pivot 154 which causes operation of an angle sensor (not shown, but which can be of the form as illustrated) as 25 potentiometer 5A in fig 9 thereby to impart a signal proportional to the angular position of pivot arm 153. This - 27 angular information is utilised by the control system in the manner previously described. With reference to fig 5B, accelerator pedal 20 5 operates against arm 155 which, in turn, operates against secondary reaction surface 156 located on an extended portion of pivot arm 157 of angular sensor 158. Operation of the accelerator pedal 20 causes rotation of pivot arm 157 thereby to vary the angular position of angular sensor 10 158 thereby to impart an angle signal for use by the control system in the manner previously described. It will be observed that in this particular arrangement of fig 5A and fig 5B the secondary reaction 15 surface is located on an opposite side of pedal 20 to that of previous embodiments but nonetheless acts as a secondary reaction surface for the purpose of acting as a mechanical communicator of position of or force applied to accelerator pedal 20, 20 Referring again to fig 6, brake pedal 12 is provided on its surface with a secondary reaction surface, in this instance a pressure sensitive pad 40, incorporating a switch (not shown) , Immediately pressure is applied to the 25 brake pedal via pad 40 by the foot of a driver, the switch - 28 disables control module 14, so that manual control of braking action is returned to the driver. Mounted within easy reach of the driver, preferably on the dashboard or, in a system fitted to a vehicle as 5 original equipment, incorporated in the wiper or indicator stalks, is an enable control 7 for control module 14. The control can comprise an illuminated button which illuminates when and only when the system is on. By means of this control, a driver may select to operate the 10 vehicle's braking system via the accelerator, or to retain normal manual control of the brake pedal, Also mounted within easy reach of the driver are two dial controls, by which operating characteristics of the accelerator braking system of the invention may be modified 15 to suit the preferences of a driver. The first of these controls 3 allows a driver to vary the rate at which the servo motor of the control module 14 responds to input signals received from the accelerator pedal's secondary reaction surface. The second control 4 allows the driver to 20 select the percentage of the maximum available braking force of the vehicle as the maximum to be applied by the control module 14. Preferably, the system is further provided with an indicator light 8 mounted in view of the driver which 25 indicates when the secondary reaction surface and the accelerator pedal are in the neutral feel zone, that is to - 29 say, when a moving vehicle is coasting, with no acceleration applied to the engine or any retarding force applied by the brakes. 5 In use Figure 7 shows graphically an example of the interaction of the movement of the top end of accelerator pedal 20, with the operation of the vehicle's brakes (refer figures 5A, 5B). 10 In this example, at vehicle start up, with the accelerator braking system of the invention enabled, the control module 14 holds the brake pedal 12 in a depressed state to exert a braking force of 140Nm (the maximum braking force selected by the driver - adjustable - in this 15 example = 60% of maximum braking force). At this point, the accelerator pedal 20 has not moved. It can be seen from the graph that as pressure is applied to the secondary reaction surface, the accelerator pedal braking force decreases under the programmed control 20 of the control module 14. Thus in the case of the accelerator pedal 20 (of figures SA, 5B), when, in this example, it has moved its full braking zone travel of approximately 25 mm, the brakes are fully off. In the example of Figure 7, the movement of 10mm of the top end of 25 accelerator pedal 20, is translated by the control module 14 servo motor as 4mm of releasing movement of the brake - 30 pedal from its 60% maximum braking state, with a concomitant reduction in the braking force to 83Nm. Referring still to Figure 7, when the vehicle is in motion and the accelerator braking system is enabled, a 5 driver may remove pressure on the accelerator pedal to the point where the accelerator pedal is fully retracted from its depressed state. This causes the control module to gradually depress the brake pedal and apply a corresponding proportion of the maximum set braking force, bringing the 10 vehicle to a braked standstill, Figure 7 provides a non-limiting example of typical movement distances for the brake pedal and the accelerator pedal on a contemporary passenger vehicle, together with typical forces that may be applied to the brake pedal with 15 reference to the embodiments shown in Figures 5A, 5B. It will be observed that the accelerator pedal may travel 25mm in the braking zone 42 (refer figure 2) whilst, at the same time, the brake pedal (refer Y axis of the graph in figure 7) will travel over a 35mm range of movement as driven by 20 the servo motor. When the accelerator pedal is at its zero position (no foot pressure applied), then, typically, the brake pedal will be at its starting position, with the servo motor having pulled down to a position corresponding to around 60% of maximum braking capability (refer figure 25 1). When a driver applies pressure to the accelerator pedal, it will move through the braking zone 42 a distance, - 31 typically, of 25mm to reach the beginning of the neutral zone 40. At this point, the brake pedal servo motor will have allowed the brake pedal to travel only 35mm back towards its brake-off position, corresponding to 5 approximately zero braking force. As the accelerator pedal is then pushed through neutral zone 40, the braking pedal simply remains at its zero force braking position, and continues to do so as the accelerator pedal is ultimately pushed through to the acceleration zone 41. 10 When the driver decides to decelerate the vehicle, the process is applied in reverse. The exception to this is when the emergency braking system, according to embodiments of the present invention, is applied, in which event the accelerator pedal movement sensor senses that the 15 accelerator pedal has been caused to move towards its deceleration position at a faster rate than normal (in at least some preferred embodiments, one order of magnitude more quickly than would typically be the case) . In this event, the brake pedal servo motor moves the brake pedal to 20 the starting position as quickly as it can, rather than proportionately to the position of the brake pedal, thereby to cause, in this embodiment, 60% braking force to be applied by the vehicle's brakes, as soon as the emergency braking condition is sensed. 25 As described elsewhere, in utilising the hardware of various embodiments described above, it is possible to - 32 adjust the brake pedal's starting position in order to achieve other percentages of brake effort other than 60% at the starting position. The adjustment can be made according to driving conditions that may be expected, or the driver's 5 personal preferences. It will be clear that a sudden release of any pressure on the accelerator pedal and, in these embodiments, the secondary reaction surface will bring the maximum set braking force into play within the adjustable reaction time 10 of the control module 14 and its actuator. This reaction time will be significantly shorter than the time it takes a driver to bring his leg and foot from the accelerator position to the brake pedal and depressing that pedal. Thus in an emergency, the initiation of considerable braking 15 force can be applied more quickly, giving the driver time to then take over and apply manually (if required) the full braking force available from the vehicle's braking system. In this emergency braking embodiment, the system is 20 arranged to sense when the accelerator pedal is released quickly from any position (including when in the braking zone, acceleration zone and neutral zone). Under this condition of relatively rapid release of the accelerator pedal, the control module is programmed, on sensing the 25 corresponding relatively rapid rate of movement of the accelerator pedal by the accelerator pedal sensor, to - 33 activate maximum braking power immediately. Any other program sequence is bypassed under this emergency braking scenario. It will be understood that "relatively rapid" may include, for example, an accelerator pedal movement in the 5 deceleration direction which is 10 times faster than in typical driving conditions. In some embodiments, the control system can be made adaptive whereby it learns typical acceleration pedal movements from normal driving conditions, and can then set boundary conditions which, 10 when exceeded, can be interpreted as an emergency condition. The emergency braking system described above has been described in the context of a variation to the three-zone accelerator pedal with braking action system, which has 15 been made the subject of the applicant's earlier international patent applications, previously referenced. It will be understood that the emergency braking system of the present application may remain in operation even if the three-zone accelerator pedal system is fitted but is in a 20 deactivated state (for example, after the driver has just touched the brake pedal) . That is, the emergency braking system can operate even if the three-zone system is in its offline mode, 25 - 34 "Factory fit" embodiment With reference to fig 10, there is illustrated a further variation to the arrangement illustrated with respect to fig 9 wherein advantage is taken of the digital 5 electronic capability now pre-installed in vehicles at the factory. With reference to fig 10 like components are numbered as for earlier embodiments except in the 200 series so, for example, dashboard mounted indicator light 8 becomes dash 10 board mounted indicator light 208, In this instance, the majority of the functions of the control module previously described are incorporated into the vehicle's "black box" 202. That is to say most vehicles these days incorporate a vehicle control system or engine 15 management system which includes a microprocessor 240 memory 241 and A/D converters 243, 242. In particular accelerator pedal 220 has its position sensed by a potentiometer arrangement 205A or equivalent whereby a signal proportional to accelerator pedal position is passed 20 either directly as a digital signal or via analogue to digital converter 242 to microprocessor 240 within the vehicle electronic control module 202. The vehicle electronic control module 202 controls many of 25 the functions of the vehicle based on data it receives from various sensors including the accelerator position sensor - 35 just described. Most vehicles also include a master cylinder (which can be combined with a vacuum assist arrangement). The master cylinder 250 is mechanically linked to the brake pedal arm 245. A sensing arrangement 5 251 communicates brake fluid pressure data via analogue to digital converter 243 to microprocessor 240. In this embodiment an auxiliary control module 252 is in electronic communication with the vehicle control module 202 and also with ancillary components of the braking system of this 10 embodiment including the sensor light 208 and other dashboard mounted components as illustrated in Fig 10. With this fully electronic "factory fit" arrangement, there is no need to install any components on the driver's 15 side of fire wall 253 of the vehicle. In this arrangement advantage is taken of the existing sensing arrangements and data already supplied to the vehicle electronic controller 202. 20 Uphill start embodiment In a particular form the microprocessor 240 can be programmed to include a modified characteristic as compared with the accelerator/ braking profile illustrated in fig 7. That is to say, in a "hill assist" mode where the vehicle 25 is caused to brake on a sloping surface, the "neutral zone" behaviour characteristic is by-passed with the vehicle - 36 proceeding from braking mode direct to powered mode, so that there is no roll back of the vehicle on the sloping surface. 5 VARIATIONS Variations within the scope of the present invention include: 1. In one version the actuator can be pivoted at both ends and pivoted in the middle of the flange 10 and fastened to the brake pedal arm. 2. In a further version the system can be programmed for automatic cutout such that when the driver places a foot on the brake pedal the above described accelerator pedal system is 15 automatically de-activated. This can be programmed as an adjunct to the existing brake servo system without requiring a sensor under the brake pedal or brake pad. 3. In another version the system is programmed so 20 that force sensing overrides distance sensing in the actuator. 4. In yet another version, the actuator can move freely in its disconnected position and a hinge bracket is installed between the end of the 25 actuator piston and a fixing point in the - 37 firewall. This is a fail safe device in case the piston becomes seized. 5. In yet a further version, the custom settings for response time of the system can include comfort 5 (slow response), sport (medium response), and sport plus (quick response). 6. In a further version, the response force of the system can be adjusted by the user by a dial control mounted for example on the dashboard. 10 The above describes .only some embodiments of the present invention and modifications, obvious to those skilled in the art, can be made thereto without departing from the scope of the present invention.

Claims

1. An emergency accelerator braking system for a vehicle; said vehicle including and accelerator pedal and a separate brake pedal for control of said vehicle; said 5 braking system reactive to position and movement of said accelerator pedal of said vehicle; said system characterized by transmission to a control module of control pedal behaviour data comprising at least one of force data representative of force applied by a 10 driver to said accelerator pedal and position data representative of the relative position of said accelerator pedal, and wherein braking force is gradually increased and decreased by operation of the accelerator pedal over at least a portion of travel of 15 said accelerator pedal; said system arranged to switch to an emergency braking mode on sensing rapid movement of said accelerator pedal above a predetermined threshold value in a decelerating direction.

2. The emergency accelerator braking system for a vehicle 20 as claimed in claim 1 wherein said predetermined threshold value is measured as rate of angular movement of said accelerator pedal about a pivot point of said pedal. - 39

3. The emergency accelerator braking system for a vehicle as claimed in claim 1 or claim 2 wherein said predetermined threshold value is measured as rate of movement of at least a portion of said accelerator 5 pedal about a pivot point of said pedal.

4. The emergency accelerator braking system for a vehicle as claimed in claim 3, wherein said portion of said accelerator pedal is a top portion of said accelerator pedal. 10

5. The emergency accelerator braking system for a vehicle as claimed in any one of claims 2 to 4, wherein said pivot point is located at or near a base portion of said accelerator pedal.

6. The emergency accelerator braking system for a vehicle 15 as claimed in any previous claim, wherein said predetermined threshold value is a multiple of the highest value achieved in normal operation of said accelerator pedal.

7. The emergency accelerator braking system for a vehicle 20 as claimed in claim 6, wherein said multiple is 2.

8. The emergency accelerator braking system for a vehicle as claimed in claim 6, wherein said multiple is 10. - 40

9. The system of any one of claims 1 to B wherein said accelerator pedal operates in zone mode (as defined in this specification) and wherein said emergency braking mode operates on sensing rapid movement of said 5 accelerator pedal from any position including acceleration zone, braking zone or neutral zone.

10. The system of claim 9 operating with zone mode in operation (on-line mode).

11. The system of claim 9 operating according to the 10 diagram of Fig 7 in on-line mode.

12. The system of claim 9 operating with zone mode switched off (off-line mode).

13. The system of claim 9 operating according to the diagram of fig 7 in off-line mode. 15

14. The system of any previous claim including an accelerator braking system for said vehicle operable in zone mode; said braking system reactive to forces applied to a secondary reaction surface of said accelerator pedal of said vehicle. 20

15. The system of any previous claim wherein said control module includes a servomotor acting on said braking system. - 41

16. The system of claim 15 wherein said servomotor acts on said separate brake pedal of said braking system.

17. The system of any one of claims 14 to 16 wherein said secondary reaction surface comprises a hinged 5 auxiliary pedal attached to said accelerator pedal; said hinged auxiliary pedal arranged for movement from a first deactivated state to a second fully activated state by pressure applied by a foot of a driver.

18. The system of claim 17 wherein said hinged auxiliary 10 pedal includes a sensor in electronic communication with said control module.

19. The system of claim 17 or 18 wherein, in said fully activated state, additional pressure applied by said foot of said driver is transferred to said accelerator 15 pedal so as to urge said accelerator pedal into an activated position.

20. The system of any one of claims 17 to 19 wherein pressure applied by said foot of a driver to urge said secondary reaction surface from said deactivated state 20 to said fully activated state is less than pressure required to urge said accelerator pedal from a deactivated state into a said activated position. - 42

21. The system of any one of claims 17 to 20 wherein transition from said fully activated state of said secondary reaction surface to a said activated position of said accelerator pedal includes a neutral 5 feel zone perceptible to said driver.

22. The system of claim 21 wherein an indicator light mounted in view of a said driver of said vehicle is activated when pressure applied to said accelerator pedal is in said neutral feel zone. 10

23. The system of any one of claims 17 to 22 wherein a transition from a said inactive state to a said fully activated state of said secondary reaction surface, is accompanied by a transition of said braking system from at least a percentage of full braking force to a 15 zero braking force.

24. The system of any one of claims 1 to 23 wherein said accelerator braking system is enabled in zone mode by a suitably mounted enable switch within reach of a driver of said vehicle. 20

25. The system of claim 24 wherein said enable switch is illuminated when and only when the system is enabled in zone mode. - 43

26. The system of claim 24 or 25 including an additional illuminated sign which includes indicia which communicate to the driver that the system is operating in zone mode. 5

27. The system of any one of claims 1 to 25 wherein said brake pedal is provided with a secondary reaction surface; said secondary reaction surface comprising a pressure sensitive pad incorporating a disable switch, whereby pressure applied to said secondary reaction 10 surface operates said switch to deactivate said control module.

28. The system of any one of claims 24 to 27 wherein a range of said braking force between said zero braking force and said at least a percentage of full braking 15 force (up to 100% of braking force) is adjustable from a dial control mounted within reach of a said driver of said vehicle.

29. The system of any one of claims 24 to 28 wherein rate of response of said control module to said 20 transmission of force data between said zero braking force and said at least a percentage of full braking force is adjustable from a dial control mounted within reach of a said driver of said vehicle,

30. The system of any one of claims 1 to 29 wherein said system is turned off when a foot is placed on said brake pedal.

31. The system of any one of claims 1 to 30 wherein an 5 "on" switch is available to switch the system on.

32. The system of claim 31 wherein said switch is illuminated when said system is on.

33. The system of claim 31 or 32 wherein a "coasting light" is illuminated when said accelerator pedal is 10 in said neutral feel zone.

34. A method of reducing reaction time between a perceived need to brake a vehicle and application of the brakes of said vehicle; said method including the steps of: providing a secondary reaction surface to an 15 accelerator pedal of a said vehicle, electronically linking said secondary reaction surface with a control module acting on a brake pedal of said vehicle; said system arranged to switch to an emergency braking 20 mode on sensing rapid movement of said accelerator pedal in a decelerating direction. - 45

35. The method of claim 34 wherein said secondary reaction surface is operable between an inactivated state and a fully activated state.

36. The method of claim 34 or 35 wherein said control 5 module activates said brakes of said vehicle between at least a percentage of full braking force and zero braking force, as force applied to said secondary reaction force varies between zero and a maximum.

37. A method of braking a vehicle by means of interaction 10 between a secondary reaction surface applied to an accelerator pedal, and a control module; said control module acting on a brake pedal of said vehicle; said method including the steps of: arranging said secondary reaction surface to 15 respond to pressure from a driver of said vehicle between a first deactivated state and a fully activated state. arranging -said control module to act on a brake pedal of said vehicle, between applying at least a 20 percentage of full braking force and a zero braking force as said secondary reaction surface responds between said first deactivated state and said fully activated state; - 46 said system arranged to switch to an emergency braking mode on sensing rapid movement of said accelerator pedal in a decelerating direction.

38. A method of urging a vehicle into motion by means of 5 operation of an accelerator pedal of said vehicle; said method including the steps of: applying a first increasing pressure to a secondary reaction surface of said accelerator pedal, increasing said first increasing pressure to a 10 maximum reaction point of said reaction surface so as to disengage a braking system of said vehicle, applying a second increasing pressure to said secondary reaction surface so as to urge said accelerator pedal into a depressed state, 15 whereby the state of said vehicle is changed from a braked standstill to a state of motion; said system arranged to switch to an emergency braking mode on sensing rapid movement of said accelerator pedal in a decelerating direction. 20

39. A method of bringing a vehicle to a standstill by means of operation of an accelerator pedal of said vehicle; said method including the steps of: - 47 applying a first decreasing pressure to a secondary reaction surface of said accelerator pedal in a depressed state, decreasing said first decreasing pressure to a 5 point at which said accelerator pedal is fully retracted from said depressed state, applying a second decreasing pressure to said secondary reaction surface, decreasing said second decreasing pressure to a 10 point where there is no pressure applied to said secondary reactions surface, whereby the state of said vehicle is changed from one in motion to a state of braked standstill; said system arranged to switch to an emergency braking mode on 15 sensing rapid movement of said accelerator pedal in a decelerating direction.

40. A method of control of a vehicle; said vehicle having an accelerator pedal and a separate brake pedal; said method comprising communicating accelerator pedal 20 position data to a controller; on the basis of position of said accelerator pedal as determined by said accelerator position data; causing a signal to be sent from said controller to a brake controller as a - 48 function of said accelerator pedal position data thereby to operate said brake pedal; said system arranged to switch to an emergency braking mode on sensing rapid movement of said accelerator pedal in a 5 decelerating direction.

41. A method of urging a vehicle into motion by means of operation of an accelerator pedal of said vehicle; said method including the steps of: (a) applying a first increasing pressure to said 10 accelerator pedal, (b) increasing said first increasing pressure to a maximum reaction point so as to disengage a braking system of said vehicle, (c) applying a second increasing pressure to said 15 accelerator pedal so as to urge said accelerator pedal into a depressed state, whereby the state of said vehicle is changed from a braked standstill to a state of motion; said system arranged to switch to an emergency braking mode on 20 sensing rapid movement of said accelerator pedal in a decelerating direction. - 4-9

42. A method of bringing a vehicle to a standstill by means of operation of an accelerator pedal of said vehicle; said method including the steps of: (a) applying a first decreasing pressure to said 5 accelerator pedal in a depressed state, (b) decreasing said first decreasing pressure to a point at which said accelerator pedal is fully retracted from said depressed state, (c) applying a second decreasing pressure to said 10 secondary reaction surface, (d) decreasing said second decreasing pressure to a point where there is no pressure applied to said secondary reactions surface, whereby the state of said vehicle is changed from one 15 in motion to a state of braked standstill; said system arranged to switch to an emergency braking mode on sensing rapid movement of said accelerator pedal in a decelerating direction.

43. An accelerator braking system for a vehicle; said 20 braking system reactive to forces applied to an accelerator pedal of said vehicle; said system characterized by a transmission to a control module of data corresponding to said forces applied to said - 50 accelerator pedal wherein braking force is gradually increased and decreased by operation of the accelerator pedal; said system arranged to switch to an emergency braking mode on sensing rapid movement of 5 said accelerator pedal in a decelerating direction.

44. The system of claim 43 wherein said braking force is a function of the forces applied to said accelerator pedal at least over a portion of the range of forces applied to said accelerator pedal. 10

45. An accelerator braking system for a vehicle; said braking system reactive to forces applied to an accelerator pedal of said vehicle; said system characterized by a transmission to a control module of force data or angle data wherein braking force is 15 gradually increased and decreased by operation of the accelerator pedal; said system arranged to switch to an emergency braking mode on sensing rapid movement of said accelerator pedal in a decelerating direction.

46. The system of claim 45 wherein said braking force is 20 applied is a function of the forces applied to said accelerator pedal at least over a portion of the range of forces applied to said accelerator pedal. - 51

47. The system of claim 45 or 46 wherein force is applied via a secondary reaction surface associated with said accelerator pedal.

48. The system of claim 47 wherein said secondary reaction 5 surface is interposed between the foot of an operator and said accelerator pedal.

49. The system of claim 47 wherein said secondary reaction surface is interposed between said accelerator pedal and an actuator surface. 10

50. The system of any one of claims 45 to 49 further including an accelerator pedal transducer associated with said accelerator pedal and wherein data is transmitted from said transducer to said control module. 15

51. The system of anyone of claims 45 to 50 including a brake pedal transducer associated with said a brake pedal of said vehicle and wherein data is transmitted from said brake pedal transducer to said control module. 20

52. The system of any one of claims 45 to 51 wherein said control module comprises an engine control module of said vehicle; said engine control module controlling - 52 operation of the engine and related components of said vehicle.

53. The system of any one of claims 45 to 52 wherein said control module includes a servomotor acting on said 5 braking system.

54. The system of claim 53 wherein said servomotor acts on a brake pedal of said braking system.

55. The system of claim 53 or 54 wherein said servomotor is connected to a portion of a pedal arm of said brake 10 pedal by means of a flexible coupling.

56. The system of any one of claims 45 to 55 wherein said secondary reaction surface comprises a pressure sensitive mat covering at least a portion of said accelerator pedal; said pressure sensitive mat 15 reactive to pressure applied by a foot of a driver between a first deactivated state and a second fully activated state of said pressure sensitive mat.

57. The system of claim 56 wherein said pressure sensitive mat includes a load cell in electronic communication 20 with said control module.

58. The system of any one of claims 45 to 58 wherein said secondary reaction surface comprises a hinged auxiliary pedal attached to said accelerator pedal; - 53 said hinged auxiliary pedal arranged for movement from a first deactivate state to a second fully activated state by pressure applied by a foot of a driver.

59. The system of claim 56 wherein said hinged auxiliary 5 pedal includes a sensor in electronic communication with said control module.

60. The system of any one of claims 45 to 59 wherein, in said fully activated state, additional pressure applied by said foot of said driver is transferred to 10 said accelerator pedal so as to urge said accelerator pedal into an activated position.

61. The system of any one of claims 45 to 60 wherein pressure applied by said foot of a driver to urge said secondary reaction surface from said deactivated state 15 to said fully activated state is less than pressure required to urge said accelerator pedal from a deactivated state into a said activated position,

62. The system of any one of claims 45 to 61 wherein transition from said fully activated state of said 20 secondary reaction surface to a said activated position of said accelerator pedal includes a neutral feel zone perceptible to said driver.

63. The system of any one of claims 30 to 49 wherein an indicator light mounted in view of a said driver of said vehicle is activated when pressure applied to said accelerator pedal is in said neutral feel zone. 5

64. The system of any one of claims 45 to 62 wherein a transition from a said inactive state to a said fully activated state of said secondary reaction surface is accompanied by a transition of said braking system from at least a percentage of full braking force to a 10 zero braking force.

65. The system of any one of claims 45 to 64 wherein said accelerator braking system is enabled by a suitably mounted enable switch within reach of a driver of said vehicle. 15

66. The system of claim 65 wherein said enable switch is illuminated when and only when the system is enabled.

67. The system of any one of claims 45 to 66 wherein said brake pedal is provided with a secondary reaction surface; said secondary reaction surface comprising a 20 pressure sensitive pad incorporating a disable switch, whereby pressure applied to said secondary reaction surface operates said switch to deactivate said control module. - Do

68. The system of any one of claims 45 to 67 wherein a range of said braking force between said zero braking force and said at least a percentage of full braking force (up to 100% of braking force) is adjustable from 5 a dial control mounted within reach of a said driver of said vehicle.

69. The system of any one of claims 45 to 68 wherein rate of response of said control module to said transmission of force data between said zero braking 10 force and said at least a percentage of full braking force is adjustable from a dial control mounted within reach of a said driver of said vehicle.

70. The system of any one of claims 45 to 69 wherein said system is turned off when a foot is placed on said 15 brake pedal.

71. The system of any one of claims 45 to 70 wherein an "on" switch is available to switch the system on.

72. The system of claim 71 wherein said switch is illuminated when said system is on. 20

73. The system of any one of claims 45 to 72 wherein a "coasting light" is illuminated when said accelerator pedal is in said neutral feel zone. - DO0

74. The system of any one of claims 1 to 73 wherein said emergency braking mode operates on sensing rapid movement of said accelerator pedal from any position including acceleration zone, braking zone or neutral 5 zone.

75. The system of claim 74 operating according to the diagram of fig 7 in on-line mode.

76. The system of claim 74 operating according to the diagram of fig 7 in off-line mode. 10

77. An emergency braking system as hereinbefore particularly described, with reference to what is shown in any one of figs 2 to 10.