Claims:We claim:
1. A controller (110) for gearshift assistance in a vehicle with manual transmission, said controller (110) adapted to receive an input from a sensor (102) to detect shift intention of a rider, said sensor (102) mounted on or between a shift pedal and a shift shaft of said transmission, said gearshift assistance comprises modulation of an engine torque through at least one of an ignition control, throttle control, and a fuel injection control, said gearshift assistance is provided without manipulation of a clutch by said rider, characterized in that,
said sensor (102) is a strain gauge type load sensor (102), and said controller (110) enables said gearshift assistance when a signal value of said sensor (102) crosses a threshold value.

2. The controller (110) as claimed in claim 1, wherein to enable said gearshift assistance said controller (110) further configured to check and satisfy at least one conditional parameter selected from a group comprising an engine speed, a duration of gearshift request, minimum time between consecutive gearshift requests and a clutch manipulation signal.

3. The controller (110) as claimed in claim 1, wherein said controller (110) determines said shift intention to be an upshift request and downshift request based on voltage signals of said strain gauge type load sensor (102).

4. The controller (110) as claimed in claim 1, wherein said modulation of engine torque comprises changing said engine torque to a zero level clutch torque, wherein said zero level clutch torque corresponds to a torque at which said clutch remains engaged with a crankshaft of an engine and simultaneously allows manual shifting of gears.

5. The controller (110) as claimed in claim 1, wherein said controller (110) configured to perform at least one of a torque up modulation and a torque down modulation for a downshift request and an upshift request based on operating point of said engine. .

6. A method for controlling gearshift assistance in a motorcycle with manual transmission, said method comprises the steps of:
detecting a shift intention from a sensor (102) located on or between a shift pedal and a shift shaft of said transmission;
modulating an engine torque through at least one of a throttle control, an ignition control, and an injection control, characterized by,
enabling said gearshift assistance when a signal value of said sensor (102) crosses a threshold value, wherein said sensor (102) is a strain gauge type load sensor (102).

7. The method as claimed in claim 6, wherein said enabling of said gearshift assistance comprises satisfying at least one conditional parameter selected from a group comprising an engine speed, a duration of gearshift request, a minimum time between consecutive gearshift requests, and a clutch manipulation signal

8. The method as claimed in claim 6, wherein said gearshift assistance is provided after determining said shift intention to be an upshift request and downshift request based on voltage signals of said strain gauge type load sensor (102).

9. The method as claimed in claim 6, wherein said step of gearshift assistance comprises modulating engine torque to a zero level clutch torque, wherein said zero level clutch torque corresponds to torque at which clutch is engaged with a crankshaft of an engine of said vehicle and allows manual shifting of gears.

10. The method as claimed in claim 6, comprises performing at least one of a torque up modulation and a torque down modulation for a downshift request and an upshift request based on operating point of said engine.
, 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:
The present invention relates to a controller for gearshift assistance in a vehicle with manual transmission and a method therefor.

Background of the invention:
A patent literature US7351185 discloses a transmission control device of motorcycle. A transmission control device for a vehicle for smoothly performing a transmission manipulation without a clutch manipulation. The device includes a control unit which determines a shift operation starting time based on a detection signal of a shift operation detector, and controls an intake air amount to an engine corresponding to a gear shift position detected by a gear shift position detection means thereby changing an output of the engine. The control unit obtains a target initial throttle opening corresponding to the gear shift position from a target initial throttle opening table, obtains data on throttle opening, time and an attenuation ratio corresponding to the gear shift position from a throttle opening, time and attenuation ratio table, and determines the opening time and the target throttle opening. Next, the control unit determines an injection amount and executes control to increase the intake air amount and the injection quantity.

Brief description of the accompanying drawings:
An embodiment of the disclosure is described with reference to the following accompanying drawing,
Fig. 1 illustrates a block diagram of a controller for gearshift assistance in a vehicle with manual transmission, according to an embodiment of the present invention;
Fig. 2 illustrates a basic graphs of implementation of torque intervention by the controller, according to an embodiment of the present invention, and
Fig. 3 illustrates a method for controlling gearshift assistance in a vehicle with manual transmission, according to the present invention.

Detailed description of the embodiments:
Fig. 1 illustrates a block diagram of a controller for gearshift assistance in a vehicle with manual transmission, according to an embodiment of the present invention. The controller 110 adapted to receive an input from a sensor 102 to detect shift intention of a rider. The sensor 102 mounted on or between a shift pedal and a shift shaft of the transmission. The gearshift assistance comprises modulation of an engine torque through at least one of an ignition control, a throttle control, and a fuel injection control. The gearshift assistance is provided without manipulation of a clutch by the rider, characterized in that, the sensor 102 is a strain gauge type load sensor 102, and the controller 110 enables the gearshift assistance when a signal value of the sensor 102 crosses a threshold value. The gearshift assistance is a functionality also known as quick shift, which enables shifting of gears of the vehicle while the clutch is still engaged. The rider or driver does not press a lever to disengage the clutch, instead the controller 110 controls at least one of the throttle system 104, the ignition system or injection system to facilitate the gearshift.

The modulation of engine torque is performed by the controller 110 through at least one of the ignition control using the spark plug system 114, the throttle control using the Electronic Throttle Control (ETC) system 116 and the fuel injection control using the fuel injection system 118. The sensor 102 is also known as quick shift sensor.

In accordance to the present invention, the controller 110 comprises the memory element 112 such as Random Access Memory (RAM) and/or Read Only Memory (ROM), Analog-to-Digital Converter (ADC) and a Digital-to-Analog Convertor (DAC), clocks, timers and at least one processor (capable of implementing machine learning) connected with each other and to other components through communication bus channels. The memory element 112 is pre-stored with logics or instructions or programs or applications or modules and threshold values and conditions which is/are 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 the cloud server 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.

According to the present invention, the controller 110 is preferably for a geared motorcycle. However, the controller 110 is applicable to be implemented for other geared vehicles as well such as other two wheelers, auto-rickshaws, cars, snowmobiles, water sport vehicles and the like.

According to an embodiment of the present invention, to enable the gearshift assistance, the controller 110 is further configured to check and satisfy at least one conditional parameter selected from a group comprising an engine speed, a duration of gearshift request, a minimum time between consecutive gearshift requests and a clutch manipulation signal. The effect of the parameters and respective conditions are explained with basic examples and the same must not be understood in limiting manner. Considering the parameter as engine speed, if the engine speed, measured using engine speed sensor 106, is 2000RPM and the driver’s intention is an upshift request, then controller 110 must reduce the torque for the torque intervention/modulation, which might lead to engine stall. The controller 110 checks and ensures this situation is avoided. Now considering the parameter of duration of gearshift request, the controller 110 ensures that false positives are eliminated, such as resting foot on the shift pedal, etc. Considering the conditional parameter of minimum time between consecutive gearshift requests, the controller 110 ensures that a next request must be detected after a minimum time period, only then the request is considered as valid else it is invalid. The conditional parameter involving the clutch manipulation signal signifies that if clutch is pressed, then the gearshift assistance must be disabled as the rider/driver has preferred clutch based gear change and not the gearshift assistance. The clutch manipulation signal is received from a respective sensor 108. In other words, the at least one conditional parameters can also be considered as disabling conditions for the gearshift assistance. In accordance to an embodiment, the controller 110 is provided to disable the gear assistance functionality or the quick shift functionality.

According to the present invention, the controller 110 determines the shift intention to be an upshift request and downshift based on voltage signals of the strain gauge type load sensor 102. For example, if detected voltage from the sensor 102 is above a first threshold value, such as an upper threshold, then upshift request is confirmed by the controller 110. Similarly, if the voltage detected from the sensor 102 is below a second threshold value, such as a lower threshold, then the downshift request is confirmed by the controller 110. Alternatively, the upshift request is confirmed by lower threshold and downshift request is confirmed by upper threshold. Further, both the downshift request and the upshift request are performed by the controller 110 based on at least one of the torque up modulation or the torque down modulation which in turn is selected based on the operating point/region of the engine at the instant of shift intention. However, generally and not limited to, the torque up modulation is performed when a downshift request is detected, and the torque down modulation is performed when the upshift request is detected. An example of threshold values is provided for better understanding. For example, at neutral/rest position, the sensor 102 generates 2.5 volts of signal. An upper threshold of 3 volts is set to detect upshift request and the lower threshold of 2 volts is set to detect downshift request or vice versa. Based on the type of sensor 102, the threshold values are changed. Thus, the threshold values comprises the first threshold value and the second threshold value for the upshift request and downshift request respectively.

According to an embodiment of the present invention, the controller 110 is at least one selected from a group comprising an Engine Control Unit (ECU) or Engine Management System (EMS) ECU, or external controller interfaced with the ECU.

Fig. 2 illustrates a basic graphs of implementation of torque intervention by the controller, according to an embodiment of the present invention. A first graph 200 depicts torque intervention for upshift request and a second graph 220 depicts torque intervention for downshift request. In the first graph 200 and the second graph 220, the Y-axis represents the torque and X-axis is time in respective suitable units. A signal 210 corresponds to a shift detection signal. Assume the rider is requesting around 80% torque represented by a first request signal 206. A maximum torque which can be produced is shown by max signal 204. The controller 110 realizes the request torque using the existing system of the vehicle. However, when a rising edge in the shift detection signal is found, the controller 110 immediately reduces the torque to a zero level clutch torque (represented by numeral 202), at which the clutch remains coupled to a crankshaft of the engine and the gearshift is also possible. According to an embodiment of the present invention, modulation of engine torque comprises changing said engine torque to a zero level clutch torque indicated by numeral 202. The zero level clutch torque corresponds to a torque at which the clutch remains engaged with the crankshaft of the engine and simultaneously allows manual shifting of gears. The zero level is not zero torque but a pre-calibrated torque value. At this time, the rider manually upshifts the gear without pressing the clutch. The controller 110 also checks for the conditional parameters as described above during this upshift request to validate the upshift request. As soon as the shift detection signal falls to default state, i.e. the upshift is complete, the controller 110 returns the torque level to previous level before the shift request. In other words, the controller 110 temporarily changes the maximum torque to zero level clutch torque signal 202 to ensure that the first request signal 206 does not go beyond the zero level clutch torque for smooth gear shift.

In the second graph 220, the shift detection signal 210 is same as explained for the first graph 200. Assume that the rider requests 10% torque, represented by second request signal 208, the controller 110 realizes the same meets the rider request using the existing system of the vehicle. However, when a rising edge in the shift detection signal 210 is detected, then the controller 110 increases the torque to zero level clutch torque, indicated by numeral 202, and then reduces after the downshift is complete. In simple terms, the controller 110 temporarily sets a minimum torque signal 212 to the zero level clutch torque to ensure that the second request signal 208 does not go beyond the zero level clutch torque for smooth gear shift. Further, the first graph 200 and the second graph 220 are not to scale and provided solely for the purpose of easy understanding. The present invention must not be understood in limiting manner to the same.

According to the present invention, a working of the controller 110 is envisaged using a third graph 230. The third graph 230 illustrates a mix of different signals for the upshift request from the rider/driver. A total of four signals are shown which may or may not be used for the gearshift assistance but are shown for explanation purposes. A first signal 214 represents a gear position of the vehicle, a second signal 216 represents throttle position, a third signal 218 represents engine speed, and, and a fourth signal represented by current torque request/demand from the rider i.e. the first request signal 206. The fourth signal 206 is modulated to the realized torque or the zero level clutch torque 202. All the four signals are to be understood in respective units. Further, three dashed lines and three dotted lines are shown in pairs 222, 224 and 226. The dotted line represents the time instant at which a shift intention is detected. The dashed line represents the time instant at which a torque intervention is performed by the controller 110 following the detected shift intention. It can be seen that at first instance 222, as the shift intention is detected, the controller 110 starts modulation of the torque needed to perform the gearshift assistance and just before the gear change the torque is reduced to the zero level clutch torque 202. The gear is then manually changed by the rider without pressing the clutch and without any discomfort. Once the gear is changed, the torque is brough back to the previous level, i.e. fourth signal 206, by the controller 110 using the same at least one of the throttle control, the ignition control, and the fuel injection control.

According to the present invention, the controller 110 is configured to calculate required torque demand for the requested upshift / downshift based on below:
Torque=function(relative load, engine speed)*function(gear)+Clutch friction torque
The torque demand is coordinated internally with other engine demands and released with control of throttle, fuel, and ignition.

Fig. 3 illustrates a method for controlling gearshift assistance in a vehicle with manual transmission, according to the present invention. The method comprises a step 302 which involves detecting the shift intention from the sensor 102 located on or between the shift pedal and the shift shaft of the transmission. A step 304 comprises modulating engine torque through any one of the throttle control, the ignition control, and the injection control. The method is characterized by a step 306 which involves enabling the gearshift assistance when the signal value of the sensor 102 (as detected by the sensor 102) crosses the threshold value. The sensor 102 is the strain gauge type load sensor 102.

The step 306 of enabling of the gearshift assistance further comprises satisfying at least one conditional parameter selected from the group comprising the engine speed, the duration of gearshift request, the minimum time between consecutive gearshift requests, and the clutch manipulation signal. The gearshift assistance is provided after determining the shift intention to be the upshift request and downshift request based on voltage signals of the strain gauge type load sensor 102. Further, the step of gearshift assistance comprises modulating engine torque to the zero level clutch torque. The zero level clutch torque corresponds to torque at which the clutch is engaged with the crankshaft of the engine of the vehicle and also allows manual shifting of gears. Both the downshift request and the upshift request are performed by the controller 110 based on at least one of the torque up modulation or the torque down modulation which in turn is selected based on the operating point/region of the engine at the instant of shift intention. However, generally and not limited to, the torque up modulation is performed when a downshift request is detected, and the torque down modulation is performed when the upshift request is detected.

According to the present invention, controller 110 and method to detect and complete gear change without clutch is disclosed. The present invention uses only strain gauge type load sensor 102 intelligently to detect gear change request. In one embodiment only one sensor 102 is used. The load based sensor 102 is used to detect the gear change request intelligently along with other engine parameters like engine speed, gear change request duration, duration after gear change request completion to detect and execute the gear change request from the rider without usage of clutch. The present invention facilitates a convenient and fun way of shifting gears without clutch engagement. The torque control while upshifting and downshifting achieved through throttle control, fuel injection control and ignition control. The present invention provides comfortable and relaxed riding, less strain for the rider on longer trips, not necessary to meddle with clutch and throttle for all gear shifts and faster gear shift times. The present invention combines the method of torque control with load based sensor 102 to achieve similar level of functionality as achieved by an angular sensor. Hence similar gearshift assistance functionality as angular based sensor is achieved using low cost sensor 102 with torque control method.

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.