Claims:We claim:
1. A controller (110) to determine a braking efficiency of a driver, said controller (110) configured to:
monitor parameters comprising at least a vehicle speed (102), an engine speed (104), a clutch input (106) and a throttle position (108), characterized in that,
estimate a vehicle force using rate of change of said vehicle speed (102), and identify braking zones where said vehicle force is less than a predefined threshold;
calculate, for each identified braking zones, a net deceleration force (A), an actual engine braking force (B) and a possible engine braking force (C), and
determine braking efficiency based on ratio of said actual engine braking force (B) and said possible engine braking force (C).

2. The controller (110) as claimed in claim 1, wherein said actual engine braking force (B) is determined using a lookup table (112) when engine braking conditions (114) are met.

3. The controller (110) as claimed in claim 2, wherein said engine braking conditions (114) comprises
detection of a clutch engaged state, and
at least one of detection of said throttle position (108) below a threshold value, and detection of shut OFF state of fuel supply.

4. The controller (110) as claimed in claim 2, wherein said lookup table (112) comprises actual engine braking force (B) for each of said gear position(s), wherein said actual engine braking force (B) is determined by selection of a value from said lookup table (112) corresponding to gear position(s) in said braking zones.

5. The controller (110) as claimed in claim 2, wherein said possible engine braking force (C) is determined for current gear position detected in said braking zone with reference to said lookup table (112),
wherein said possible engine braking force (C) is considered when said possible engine braking force (C) is greater than said net deceleration force (A), and
when said possible engine braking force (C) is lesser than said net deceleration force (A), said controller (110) is configured to calculate possible engine braking force (C) for downshift gear positions which is closest to said net deceleration force (A) with corresponding engine speed (104).

6. A method for determining a braking efficiency of a driver, said method comprising the steps of:
monitoring parameters comprising at least a vehicle speed (102), an engine speed (104), a clutch input (106) and a throttle position (108), characterized by,
estimating a vehicle force using rate of change of said vehicle speed (102) and identifying braking zones where said vehicle force is less than a predefined threshold;
determining, for each identified braking zones, a net deceleration force (A), an actual engine braking force (B) and a possible engine braking force (C), and
determining braking efficiency based on ratio of actual engine braking force (B) and said possible engine braking force (C).

7. The method as claimed in claim 6, wherein determining said actual engine braking force (B) is done using a lookup table (112) when engine braking conditions (114) are met.

8. The method as claimed in claim 7, wherein meeting said engine braking conditions (114) comprises
detecting a clutch engaged state, and
at least one of detecting said throttle position (108) below a threshold value, and detecting shutting OFF of fuel supply.

9. The method as claimed in claim 7, wherein said lookup table (112) comprises actual engine braking force (B) for each of said gear position(s), wherein determining said actual engine braking force (B) is done by selecting a value from said lookup table (112) corresponding to gear position(s) in said braking zones.

10. The method as claimed in claim 7, wherein determining said possible engine braking force (C) is done for current gear position in said braking zone with reference to said lookup table (112),
wherein said possible engine braking force (C) is considered when said possible engine braking force (C) is greater than said net deceleration force (A), and
when said possible engine braking force (C) is lesser than said net deceleration force (A), said possible engine braking force (C) is calculated for downshift gear positions which is closest to said net deceleration force (A).
, Description:Complete Specification:
The following specification describes and ascertains the nature of this invention and the manner in which it is to be performed:

Field of the invention:
[0001] The present invention relates to a controller and method to determine a braking efficiency of a driver.

Background of the invention:
[0002] A patent literature DE102016221622 discloses a method and apparatus for providing a braking effect of a motor vehicle. The invention relates to a method for providing a braking effect in a motor vehicle, and in particular in the context of a cooperative braking, wherein the motor vehicle has a braking device equipped with a friction brake and having an engine brake to slow the motor vehicle, wherein a braking action of the engine brake is composed of a plurality of individual braking effects (E1, E2,..., s) based on a plurality of braking mechanisms, comprising the steps of: assigning priorities (P1, P2,..., Pn) to the individual braking effects (E1, E2,..., En) of the motor-brake, selecting at least one of the individual braking effects (E1, E2,..., En) according to the assigned priorities (P1, P2,..., Pn), and deactivating the engine brake by implementing the selected individual braking (E1, E2,..., En) for providing the braking efficiency, in particular, by a parent control device, in particular of an Antilock Brake System (ABS/ESP) control unit of the control unit, Is demanded, wherein in particular the demanded braking action from a from a motor controller of the control unit cyclically to the maximum total engine-braking efficiency is limited, in particular on the basis of implemented models is determined.

Brief description of the accompanying drawings:
[0003] An embodiment of the disclosure is described with reference to the following accompanying drawing,
[0004] Fig. 1 illustrates a block diagram of a controller to determine braking efficiency of a driver, according to an embodiment of the present invention, and
[0005] Fig. 2 illustrates a method for determining braking efficiency of the driver, according to the present invention.

Detailed description of the embodiments:
[0006] Fig. 1 illustrates a block diagram of a controller to determine braking efficiency of a driver, according to an embodiment of the present invention. The controller 110 configured to, monitor parameters comprising at least a vehicle speed 102, an engine speed 104, a clutch input 106 and a throttle position 108, characterized in that, the controller 110 estimates a vehicle force using rate of change of vehicle speed 102, and identifies braking zones where the vehicle force is less than a predefined threshold (such as zero). For each identified braking zones, the controller 110 calculates, a net deceleration force (A), an actual engine braking force (B) and a possible engine braking force (C). The controller 110 then determines braking efficiency based on ratio of the actual engine braking force (B) and the possible engine braking force (C). The parameters are monitored using respective sensors such as vehicle speed sensor, engine speed sensor, clutch switch, a throttle position sensor, and the like.

[0007] The controller 110 comprises memory element (not shown) such as Random Access Memory (RAM) and/or Read Only Memory (ROM), Analog-to-Digital Converter (ADC) and vice-versa Digital-to-Analog Convertor (DAC), clocks, timers and a processor (capable of implementing machine learning) connected with the each other and to other components through communication bus channels. The memory element is pre-stored with logics or instructions or programs or applications which is accessed by the processor as per the defined routines. The internal components of the controller 110 are not explained for being state of the art, and the same must not be understood in a limiting manner. The controller 110 may also comprise communication units to communicate with a server or cloud (not shown) through wireless or wired means such as Global System for Mobile Communications (GSM), 3G, 4G, 5G, Wi-Fi, Bluetooth, Ethernet, serial networks and the like. In the case of the cloud, the processing may be done entirely by the cloud or the processing is shared between the cloud and the controller 110.

[0008] In accordance to an embodiment of the present invention, the controller 110 is the existing Engine Control Unit (ECU) of the vehicle or a separate unit interfaced with the ECU. Alternatively, an external control unit of a communication device such as smartphone, laptop, etc., is the controller 110. The external control unit is interfaced with the ECU of the vehicle through telecommunication unit via wired or wireless means such as cable, Bluetooth™, InfraRed, and known wireless communication networks. The driver/user gets notification of braking efficiency either on an output 118, such as a dashboard or a display unit of the vehicle or of the communication device of the rider/driver. In the case of communication device, the processing and display of output 118 is performed through an installed application.

[0009] The actual engine braking force (B) is determined using a lookup table 112 when engine braking conditions 114 are met. Within the braking zones, the engine braking conditions 114 comprises detection of a clutch engaged state, and at least one of detection of the throttle position 108 below a threshold value, and detection of shut OFF state of fuel supply. The lookup table 112 comprises actual engine braking force (B) for each of the gear position(s). The gear position is detectable using the ratio of engine speed 104 and vehicle speed 102 or a dedicated gear position sensor. The actual engine braking force (B) is determined by selection of a value from the lookup table 112 corresponding to the gear position(s) in the braking zones.

[0010] According the present invention, the possible engine braking force (C) is determined for current gear position detected in the braking zone with reference to the lookup table 112. The possible engine braking force (C) is considered when the possible engine braking force (C) is greater than the net deceleration force (A). Also, when the possible engine braking force (C) is lesser than the net deceleration force (A), the controller 110 is configured to calculate possible engine braking force (C) for downshift gear positions which is closest to the net deceleration force (A). While calculating the possible engine braking force (C), the engine speed 104 is checked to be under a threshold limit 116. If the engine speed 104 is greater than the threshold limit 116, then the efficiency for the corresponding braking zone is ignored as the deceleration is too high and thus outside the purview of rider/driver metrics. The values A, B and C are calculated from respective modules in the controller 110, i.e. the controller 110 calculates A, B and C using inputs from the lookup table 112, the engine braking conditions 114 and threshold limit 116.

[0011] In accordance to an embodiment of the present invention, the braking efficiency of the driver is calculated in real-time while the vehicle is being driven. Till the end of the drive cycle the braking efficiency keeps updating with the available data. In an alternative, the braking efficiency of the driver is calculated after a drive cycle is completed. The stored data in the memory element of the controller 110 is retrieved and then processed to calculate the braking efficiency. In yet another alternative, the communication device performs the processing as and when the monitored data is received from the vehicle.

[0012] According to the present invention, a working of the controller 110 is described below, which is just an example and the present invention must not be limited by the same. Consider the vehicle is a two-wheeler. The controller 110 imports the entire ride data at the end of the driver cycle. At each time instant, an acceleration (force) is estimated from the vehicle speed 102. The controller 110 designates each chunk of data where force is less than a preset/predefined threshold (such as Zero) as the braking zone. The controller 110 estimates the actual engine braking force for each braking zone using the lookup table 112 based on engine speed 104 (Rotation/Revolutions Per Minute (RPM)) and gear position. The engine braking is considered when engine braking conditions 114 are met such as when clutch not pressed, throttle position 108 is close to or equal to zero and fuel is shut OFF. For example: If in a ten seconds long braking zone, the first three seconds is driven in fourth gear, then the subsequent three seconds of clutching (for shifting) and then last four seconds is driven in third gear, the net engine braking is proportionally calculated wherever the engine braking conditions 114 are met.

[0013] For each deceleration/braking zone there are two relevant scenarios, first case where the required decelerating force achievable without downshifting, and a second case, where the required decelerating force is higher than engine braking force in the current gear. In the first case, if the net decelerating force (A) can be met by using only engine braking in current gear, then the possible engine braking force (C) is calculated for only the current gear using lookup table 112. Example, if Net decelerating force (A) = 100N, actual engine braking force is 40N, and possible engine braking force (C)=110N at fourth gear, then (C) is considered.

[0014] In the second case, if the net decelerating force (A) can only be met by downshifting then possible engine braking force (C) is calculated for the downshifted gear. Example, net decelerating force (A) = 200N, actual engine braking force = 60N, and possible engine braking force = 110N at fourth gear, and 220N at third gear, then 220N is selected with a correction factor accounting for gear shift time. Note: A braking zone where net deceleration force (A) required is so high that downshifting will not be enough or would cause the engine speed 104 to cross the threshold limit 116 (preset limit), then it is not considered in braking efficiency calculation at all. The braking efficiency is calculated as ratio of actually used engine braking force (B) to possible engine braking force (C).

[0015] The controller 110 is able to detect deceleration of the vehicle due to the following causes and their combinations, clutch, braking with clutch (friction braking), no throttle input (engine braking) and shifting to neutral. There are other causes such as half-clutch, braking without clutch, effect of gradient, etc. which are also detectable for further accuracy in the calculation of the braking efficiency. The other causes are either identified by the recorded data or are measured by specific sensors or combination of existing or new sensors in the vehicle. The controller 110 is also able to use a correction factor in place of the other parameters which is multiplied to the maximum possible engine braking.

[0016] Fig. 2 illustrates a method for determining braking efficiency of the driver, according to the present invention. The method comprises plurality of steps, of which a step 202 comprises monitoring parameters comprising at least the vehicle speed 102, the engine speed 104, the clutch input 106 and the throttle position 108, using respective sensors available in the vehicle. The method is characterized by, a step 204 which comprises estimating the vehicle force using rate of change of the vehicle speed 102 and identifying braking zones where the vehicle force is less than a predefined threshold. A step 206 comprises determining, for each identified braking zones, the net deceleration force (A), the actual engine braking force (B) and the possible engine braking force (C). A step 208 comprises determining braking efficiency based on the ratio of actual engine braking force (B) and the possible engine braking force (C).

[0017] The determining of the actual engine braking force (B) is done using a lookup table 112 when engine braking conditions 114 are met. Further, meeting the engine braking conditions 114 comprises detecting the clutch engaged state, and at least one of detecting the throttle position 108 below a threshold value, and detecting the shutting OFF of fuel supply. The lookup table 112 comprises actual engine braking force (B) for each of said gear position(s). The determining of the actual engine braking force (B) is done by selecting the value from the lookup table 112 corresponding to gear position(s) in the braking zones.

[0018] The determining of the possible engine braking force (C) is done for current gear position in the braking zone with reference to the lookup table 112. The possible engine braking force (C) is considered when the possible engine braking force (C) is greater than the net deceleration force (A). When the possible engine braking force (C) is lesser than the net deceleration force (A), then the possible engine braking force (C) is calculated for downshift gear positions which is closest to the net deceleration force (A). While calculating the possible engine braking force (C), the engine speed 104 is checked to be under a threshold limit 116. If the engine speed 104 is greater than the threshold limit 116, then the corresponding possible engine braking force (C) is ignored or not considered.

[0019] In accordance to an embodiment of the present invention, the controller 110 and method provides a user value enhancing feature, which can be used to train rider/driver by providing feedback on the riding/driving style and the impact it has on the vehicle. The present invention metricize braking characteristics and uses for rider/driver feedback purposes. The present invention comprises the controller 110 and the method to evaluate the proportion of engine braking and hydraulic/friction friction braking used in each braking zone. The engine braking is advantageous for the vehicle as well as the rider/driver due to reduced brake wear, lesser brake fade, reduced fuel consumption and smoother transients. Thus, proposed invention aims to encourage engine braking by providing rider/driver with the braking efficiency metric. This invention includes the method to collect ride data, identify braking zones and evaluate engine braking force using a vehicle specific function with vehicle speed 102, engine speed 104 and throttle position 108 as input. This is followed by evaluating a single ‘braking efficiency metric’ that encourages engine braking use over conventional hydraulic friction brakes.

[0020] It should be understood that embodiments explained in the description above are only illustrative and do not limit the scope of this invention. Many such embodiments and other modifications and changes in the embodiment explained in the description are envisaged. The scope of the invention is only limited by the scope of the claims.