The present invention relates to an electronic gear shifting technique for automobiles.
More particularly, the invention relates to E-Toggle gear shifting technique that can be used in
electric vehicle. More particularly, the invention relates to an electronic contactless gear
transmission-switch mechanism for an automatic vehicle transmission.
BACKGROUND
Generally, automobile gear shifting technology is already well known in the state of the
art and is subject to improvement through continuous research & development. Such gear
shifting technology involves n-number of gear positions such as forward gears, reverse gear, and
neutral.
However, automatic transmission through existing gear shifting technology generally
encounter various problems such as shaking or grinding sensation in gear, when the gear is
suddenly changed. Another issue that is generally encountered is that the automobile may not
engage or reciprocate when in gear. Furthermore, the automatic transmission through existing
gear shifting technology may also result in noise such as whining, humming and/or clunking, in
neutral mode.
Conventionally, contact based gear transmission switches are being used in the vehicle.
Such switches undergo a lot of problems such as low durability, short life and high probability of
mal-functionality. Even contactless switches were to be contemplated to replace the same, the
state of the art data communication and processing systems in the automobile are prone to
malfunction in terms of deciding which gear needs to be switched based on current position of
the contact-based or contactless switch.
At least to address aforesaid constraints, there lies a need for obviating aforesaid
drawbacks plaguing the state of the art of existing gear shifting technique which can be
optimized using Hall Effect sensor-based system for controlling the vehicle in drive, reverse and
2
neutral mode in time-efficient manner and with more accuracy without any overhead of
manufacturing complexity and added-costs.
SUMMARY
This summary is provided to introduce a selection of concepts, in a simplified format, that
are further described in the detailed description of the invention. This summary is neither
intended to identify key or essential inventive concepts of the invention and nor is it intended for
determining the scope of the invention.
The present disclosure relates to an electronic contactless gear transmission-switch system
and method for an automatic vehicle transmission.
In one aspect of the present invention, there is provided the electronic contactless gear
transmission-switch system which comprises a knob pivoted within a housing above a detent
profile, said knob defining a plurality of operable-positions upon actuation by a user. The -switch
system further comprises an electrical-circuit comprising a plurality of sensors to generate a
plurality of signals with respect to a plurality of positions of the knob. The -switch system further
comprises a Data Communication Bus (CAN) for communicating signals from the electrical
circuit. The -switch system further comprises a microcontroller connected to the electrical circuit
through the bus and configured for: executing a scheduler configured for detecting change in the
signal compared to last captured signal. The scheduler is adapted for detecting periodically in
accordance with a first predetermined time interval. The microcontroller is adapted for
determining a position or a combination of positions traversed by the knob based on detecting
the change in signal. The microcontroller is adapted for ascertaining an existence of the
determined position or the combination of positions for a second predetermined time interval.
The microcontroller is also adapted for outputting the determined position as one or more of
drive, reverse or neutral gear positions to a display through the bus based on the ascertaining the
existence of the determined position or the combination of positions.
In another aspect of the present invention, there is provided a method of operation of an
electronic contactless gear transmission-switch system for an automatic vehicle transmission.
The method comprising generating a plurality of signals with respect to a plurality of positions of
3
a knob by an electrical-circuit comprising a plurality of sensors, said knob defining a plurality of
operable-positions upon actuation by a user. The method further comprising communicating
signals from the electrical circuit by a data communication bus (CAN) to a microcontroller
performing by the microcontroller connected to the electrical circuit the steps of executing a
scheduler configured for detecting change in the signal compared to last captured signal, said
scheduler detecting periodically in accordance with a first predetermined time interval. The
microcontroller is further adapted for performing the step of determining a position or a
combination of positions traversed by the knob based on detecting the change in signal. The
microcontroller is further adapted for performing the step of ascertaining an existence of the
determined position or the combination of positions for a second predetermined time interval.
The microcontroller is further adapted for performing the step of outputting the determined
position as one or more of drive, reverse or neutral gear positions to a display through the bus
based on the ascertaining the existence of the determined position or the combination of
positions.
To further clarify the advantages and features of the present disclosure, a more particular
description of the disclosure will be rendered by reference to specific embodiments thereof,
which is illustrated in the appended drawings. It is appreciated that these drawings depict only
typical embodiments of the disclosure and are therefore not to be considered limiting of its
scope. The present disclosure will be described and explained with additional specificity and
detail with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS:
The present disclosure will become better understood when the following detailed
description is read with reference to the accompanying drawings in which like characters
represent like parts throughout the drawings, wherein:
FIGURE 1a illustrates a perspective view of electronic contactless gear transmissionswitch system, in accordance with an embodiment of the present invention.
4
FIGURE 1b illustrates cross sectional view of E-toggle gear shifting unit , in accordance
with an embodiment of the present invention.
FIGURE 2 illustrates a block diagram of gear shifting unit, in accordance with an
embodiment of the present invention.
FIGURE 3 illustrates a schematic view of interfacing Hall-effect/Magnetic sensor with
Microcontroller, in accordance with an embodiment of the present invention.
FIGURE 4 illustrates a control flow depicting the operation of an electronic contactless
gear transmission-switch system, in accordance with an embodiment of the present invention.
It may be noted that to the extent possible like reference numerals have been used to
represent like elements in the drawings. Further, those of ordinary skill in the art will appreciate
that elements in the drawings are illustrated for simplicity and may not have been necessarily
drawn to scale. For example, the dimensions of some of the elements in the drawings may be
exaggerated relative to other elements to help to improve understanding of aspects of the present
invention. Furthermore, the one or more elements may have been represented in the drawings by
conventional symbols, and the drawings may show only those specific details that are pertinent
to understanding the embodiments of the present invention so as not to obscure the drawings
with details that will be readily apparent to those of ordinary skill in the art having the benefits of
the description herein.
DETAILED DESCRIPTION DRAWINGS
It will be understood by those skilled in the art that the foregoing general description and
the following detailed description are explanatory of the disclosure and are not intended to be
restrictive thereof.
Reference throughout this specification to “an aspect”, “another aspect” or similar
language means that a particular feature, structure, or characteristic described in connection with
the embodiment is included in at least one embodiment of the present disclosure.
5
Reference throughout this specification to “an aspect”, “another aspect” or similar
language means that a particular feature, structure, or characteristic described in connection with
the embodiment is included in at least one embodiment of the present disclosure. Thus,
appearances of the phrase “in an embodiment”, “in another embodiment” and similar language
throughout this specification may, but do not necessarily, all refer to the same embodiment.
The terms "comprises", "comprising", or any other variations thereof, are intended to cover
a non-exclusive inclusion, such that a process or method that comprises a list of steps does not
include only those steps but may include other steps not expressly listed or inherent to such
process or method. Similarly, one or more system or unit or sub-systems or elements or
structures or components proceeded by “comprises… a” does not, without more constraints,
preclude the existence of other UE or other sub-systems or other elements or other structures or
other components or additional sub-systems or additional elements or additional structures or
additional components.
Unless otherwise defined, all technical and scientific terms used herein have the same
meaning as commonly understood by one of ordinary skilled in the art to which this disclosure
belongs. The system, method, and examples provided herein are illustrative only and not
intended to be limiting.
The present disclosure relates to automobile gear shifting technology, and more
particularly to an electric control method for an Electric Vehicle in which an Electronic Control
Unit (ECU) of the vehicle may be employed to direct and maintain the gear shifting system. The
automobile gear shifting technology involves Hall Effect sensor-based system that helps in
precisely controlling the vehicle in drive, reverse and neutral mode.
FIGURE 1a depicts a perspective view of electronic contactless gear transmission-switch
system 1010, in accordance with an embodiment of the present invention.
The E-toggle gear shifting unit 1000 or E-toggle gear shifter 1000 may be interchangeably
used. The E-toggle gear shifting unit 1000 comprises at least a toggle knob 101 that can be
moved by a user for changing the position of gear. The toggle knob or knob 101 is pivoted
within a housing of the E-toggle gear shifting unit 1000 above a detent profile or a cam profile.
6
The knob 101 traverses the cam profile based on a spring loaded plunger. Accordingly, the knob
101 defines a plurality of operable positions upon actuation by a user. The detent profile is
configured as a set of grooves and peaks to correspond to the gear positions (R, N. D) and
additionally two intermediate gear positions.
At least three positions are provided for the operation of E-toggle gear shifting unit 1000.
The positions are as follows: a reverse position 100, a neutral position 102, and drive position
103. The default position of the gear is at neutral position 102. The reverse position 100 is
denoted by “R”, the neutral position 102 is denoted by “N”, and the drive position 103 is denoted
by “D”. The gear shifting unit 1000 further comprises an electrical-circuit or PCB (shown in
Figure 1b) comprising a plurality of sensors to generate a plurality of signals with respect to a
plurality of positions of the knob 101.
The E-toggle gear shifting unit 1000 provides an automatic transmission in accordance
with exemplary aspects of the present disclosure. It is preferably provided that one of the shifts
of gear from neutral 102 is directly connected to a forward drive mechanism. Similarly another
shift of gear from neutral 102 is directly connected to a reverse mechanism.
The information from the E-Toggle shifting unit 1000 is communicated to one or more
Electronic Control Units (ECU) 107 via a Data Communication (CAN) Bus 106. The ECU 107
is connected on CAN bus 106 to receive information at least related to variation in switch
condition of the E-toggle gear shifting unit 1000.
The ECU 107 is connected to an electrical circuit embedded in the gear shifting unit 201
through the CAN bus 106 and configured for executing a scheduler The scheduler is in turn
configured for detecting change in the signal compared to last captured signal. In particular, the
scheduler is adapted for periodically detecting change in accordance with a first predetermined
time interval. The scheduler is configured for executing a program counter (PC) based checking
of a sensor status as a part of detecting the signal change. In an example, said counter is defined
by time period of 10 ms as the first predetermined time interval.
The ECU 107 is further configured for determining a position or a combination of
positions traversed by a knob 101 based on detecting the change in signal. The ECU 107 is
7
further configured for ascertaining an existence of the determined position or the combination of
positions for a second predetermined time interval, which corresponds to a debounce time, and
outputting the determined position as one or more of drive (D), reverse (R) or neutral (N) gear
positions to a display through the bus based on the ascertaining the existence of the determined
position or the combination of positions. The determining of the position or a combination of
positions corresponds to checking the combination of positions covered by a toggle switching
element of the knob 101.
Figure 1b depicts a cross sectional view of E-toggle shifting unit 3000 in accordance
with an embodiment of the present invention. The E-toggle gear shifting unit 3000 comprises an
electrical-circuit 300, casing 301, and a gear knob 302. The electrical-circuit 300 further
comprises a plurality of sensors 303-307 to generate a plurality of signals with respect to a
plurality of positions of the knob 302. Each sensor 303-307 has the predefined position and
distance from a magnet 208 embedded within the gear knob 302.
The E-toggle shifting unit 3000 is referred as E-Toggle shifting unit 1000 in Figure 1.
The E-toggle shifting unit 3000 of the present subject matter is subject to the task of controlling
the speed and movement of the vehicle. Such task of controlling the speed and movement of the
vehicle may be achieved by driving the gear knob 302 provided in the E-toggle shifting unit
3000 in specific direction according to the aspects of the invention. The gear knob 302 is referred
as toggle knob 101 in Figure 1a.
The cam profile allows the knob 302 to attain five positions such as B2, B1, H, F1, and
F2 as depicted in Figure 1b. Any of the positions B1, F1, H when considered individually
correspond to neutral positions. A combination of positions B2 & B1 corresponds to reverse
position. Another combination of positions F2 & F1 corresponds to forward drive position. B2
and F2 corresponds to first and second extreme positions, F1 and B1 correspond to first and
second intermediate positions, and H corresponds to a middle position.
As a non-limiting factor, the knob 302 which corresponds to a toggle switching element
is defined by a switching-step of a predetermined size of 4.5 mm, as also depicted in Figure 1b.
The determining the position or a combination of positions corresponds to checking the
8
combination of positions traversed by the knob 302 may be based on detecting the change in
signal, which may result in displacement of the toggle switching element 101, 302.
The electrical-circuit 300 is a Hall Effect based device or a Hall sensor-based PCB 300
comprising a plurality of Hall elements 303-307 acting as the plurality of sensors 303-307. When
the Hall Effect sensor 303-307 is placed in the magnetic field or in the vicinity of a magnet, the
magnetic flux lines exert a force on semi-conductor material, which deflects the charge carriers,
electrons and holes as well to either side of the semiconductor materials. The movement of
charge carriers is a result of magnetic force, electrons and holes move side wards a potential
difference is produced between the two sides of the semiconductor materials is affected by the
presence of an external magnet or magnetic field.
Each Hall Effect sensor 303-307 is positioned, equidistantly, within the casing or housing
301. The purpose of using the Hall Effect sensors 303-307 is for the precisely and accurately
sensing at least a position and distance of the gear knob 302. The Hall Effect sensor 303-307 is
adapted to respond at least to positive and negative magnetic fields with minimal probabilities of
imprecision. The output signal obtained from these Hall Effect sensors 303-307 is a function of
magnetic field density around it. When the magnetic flux density around the Hall Effect sensor
303-307 exceeds a certain pre-set threshold, the Hall Effect sensor 303-307 detects it and
accordingly, generates an output voltage which can be electrically communicated to the ECUs
107 through the CAN bus 106.
As a non-limiting aspect of the present disclosure, the position of the knob 302 is sensed
at least with the help of plurality of Hall Effect sensors 303-307. For example, as also referred in
Figure 1b, the position of the knob 302 is sensed with the help of five Hall Effect sensors 303-
307 wherein at least two Hall Effect sensors 303-307 are used for sensing the forward shifting,
other two Hall Effect sensors 303-307 are used for sensing the reverse direction and one is for
sensing the neutral or the default position of the gear knob 302.
The outputting of the determined position comprises outputting at least a Drive position
based on determining the combination of position as a first intermediate position and a first
9
extreme position and a Reverse position based on determining the combination of position as a
second intermediate position and a second extreme position.
Accordingly, in a first solution in accordance with exemplary aspects of the invention,
the gear knob 302 is adapted to move in forward direction from its neutral position, which is
denoted by “H” in Figure 1b. At least two positions that are first forward position “F1” and
second forward position “F2” are defined for the gear knob 302 to advance in forward direction
from its neutral position, H. In the present scenario, if the user needs to change the gear from
neutral to drive mode, then the user must drag the gear knob 302 to cover F1, F2, F1 and H.
In a second solution in accordance with exemplary aspects of the invention, the gear knob
302 is adapted to move in reverse direction from its neutral position, H, as shown in Figure 1b.
At least two positions that are first backward position “B1” and second backward position “B2”
are defined for the gear knob 302 to advance in backward direction from its neutral position, H.
In the present scenario, if the user needs to change the gear from neutral to reverse mode, then
the user has to drag the gear knob 302 to cover to B1, B2, B1 and H.
FIGURE 2 illustrates a block diagram of gear shifting unit 2000, in accordance with an
embodiment of the present invention.
In an embodiment, a gear shifting unit 2000 is provided which is electrically driven
through a power supply 2003. The power supply 2003 is provided with input port(s) 2001 and
2002 and an output port 2004. The input port(s) 2001 and 2002 are adapted to receive input
supply from the vehicle side that is V-battery and Ignition.
The power supply is provided with a protection module which is adapted to filter out the
unwanted surges and transients and accordingly converts filtered signals into the Vcc supply.
This generated supply is further transmitted to a plurality of sensors 2005, 2006, 2007, 2008 and
2009, a microcontroller unit 2013 and other sub-elements. The filtered supply from the Vbattery
and/or ignition may be provided further to one or more Feedback Indicator 2011.
The microcontroller 2013 is configured to communicate with a plurality of Hall Effect
sensors 2005-2009. The microcontroller 2013 is further configured to receive signals from the
10
Feedback Indicator 2011 for processing related to the gear shifting. The processed information
from the microcontroller 2013 is communicated to a CAN transceiver 2012.
Figure 3 depicts a schematic view of interfacing Hall-effect/Magnetic sensor with
Microcontroller, in accordance with the present subject matter.
The Hall Effect sensor 3002, 3005, 3007, 3009 and 3011 are connected with the
microcontroller (which is referred as microcontroller 2013 in Figure 2, but not shown in Figure
3). An interfacing arrangement is provided with help of the Vcc and ground supply. As seen
from the figure 3, Vcc is connected with the Vin and Vout side with using electronic components
to perform filtration and current controlling,
In absence of magnet upon sensors (3002, 3005, 3007, 3009 and 3011), the circuit is open
circuit. In such a scenario, the state of electrical points 3003, 3006, 3008, 3010, 3012 within the
circuit is ON and equivalent to the Vcc voltage. All sensors 3002, 3005, 3007, 3009 and 3011 are
connected individually with microcontroller 2013 to monitoring the status of each sensor
individually.
As magnet is present upon on any of the Hall Effect sensor: (3002, 3005, 3007, 3009 and
3011, the corresponding sensor will be active and accordingly completes an electrical circuit by
connecting Vout to GND internally. Due, to this, output voltage is pulled down to Zero. As a
result, the, microcontroller 2013 will sense and figure out about a particular activated sensor for
further process.
Figure 4 depicts a control flow 400 depicting the operation of an electronic contactless
gear transmission-switch system 1010, in accordance with an embodiment of the present
invention.
In an embodiment of the present disclosure, there is provided a method of operation of an
electronic contactless gear transmission-switch system 1010 for an automatic vehicle
transmission. In an implementation, the method of operation of an electronic contactless gear
transmission-switch system 1010 comprises the forthcoming operation.
11
When a user is rendered access to control the E-toggle gear shifter 1000, 3000 by
changing the position of the knob 101, 302 provided over the E-toggle gear shifter 1000, 3000, a
plurality of signals is generated, with respect to a plurality of positions of a knob 101, 302, by an
electrical-circuit 300 comprising a plurality of sensors. The sensors may be represented by
sensors 303-307 of Fig. 1, 2005-2009 in Fig. 2, and 3002-3011 of Fig. 3. The knob 101, 302
defines a plurality of operable positions upon actuation by the user. The plurality of operable
positions are the position such as drive (D) or reverse (R) or neutral (N) gear positions or a
combination of these positions covered by a toggle switching element as discussed in reference
to Figure 1b.
The signals from the electrical circuit 300, 2000 are communicated by a data
communication bus (CAN) 106, 2012 to an Electronic Control Units (ECU) or a microcontroller
107, 2013, as also referred in Figure 1a and Figure 2, wherein the signals from the E-Toggle
shifting unit 201 is communicated to one or more Electronic Control Units (ECU) 107, 2013 via
a Data Communication (CAN) Bus 106, 2012. Further, the ECU 107, 2013 are connected on
CAN bus 106, 2012 to receive information at least related to variation in switch condition of the
E-toggle gear shifting unit 1000, 3000.
The ECU or microcontroller 107, 2013 is connected to the electrical circuit 300, 2000
performs the following steps of operation in forthcoming paragraph.
At steps 401: A scheduler is configured for executing a Program Counter (PC)-based
checking of a sensor status as a part of detecting the signal change, where the counter is defined
by a first predetermined time interval. In other words, the scheduler is configured for detecting
change in the signal compared to last captured signal.
At step 402: The Program Counter (PC) embedded in the E-toggle gear shifter 1000,
3000 checks the sensor status periodically after the first predetermined time interval. As a nonlimiting factor, this first predetermined time interval is selected as 10ms. At this stage, the status
may either remain same or may change.
12
If in case the status is not updated, Step 402A is followed and the information regarding
the previous status is communicated back to the scheduler. The Control flow terminates here and
transfers to step 401 upon an elapse of the first predetermined time interval.
If in case the status is updated, the control from step 402 transfers to Step 403. The
combination of the toggle is checked at Step 404. In other words, based on the detected change
in signal, one of the following position or a combination of positions is determined which is
traversed by the knob. Following steps 405 till 410 illustrate various positions or combination of
the positions.
At step 405: combination of positions for detecting the Reverse mode is
HB1B2B1H. In this configuration, by default the magnet remains at the H position, as
also referred in Figure 1b. In other words, the sequence to achieve the Reverse Mode is when the
magnet traverses from B1 position to B2 position, then again traverses back to H position
through B1.
At step 406: combination of positions for detecting the Forward mode is
HF1F2F1H. In this configuration, by default the magnet remains at the H position, as
also referred in Figure 1b. In other words, the sequence to achieve the Reverse Mode is when the
magnet reaches the F1 position, further traverses to F2 position, and then traverses back to H
Position through F1.
At step 407: combination of positions for detecting the neutral position from any Forward
or Reverse mode is HF1H)||(HB1H). The E-toggle gear shifter unit stays on the neutral
position, in case a user intends shift the gear to the neutral position after using the any one of the
reverse or forward modes In this configuration, since by default, the magnet remains at the H
position, therefore to activate neutral, the user has to traverse the gear either to the F1 position or
B1 position which eventually itself reaches back to the H position.
At step 408: an existence of the determined position or the combination of positions for a
second predetermined time interval is ascertained. In other words, after debounce time, the
13
combination of positions HB1B2B1H Signal is confirmed. Likewise step 409 till 413
represented confirmation of other positions upon elapse of the debounce time.
At step 409: an existence of another determined position or the combination of positions
for a second predetermined time interval is ascertained. In other words, after debounce time, the
combination of positions HF1F2F1H Signal is confirmed.
At step 410: an existence of another determined position or the combination of positions
for a second predetermined time interval is ascertained. In other words, after debounce time, the
combination of positions HF1H)||(HB1H) Signal is confirmed.
At Step 411: The microcontroller 107, 2013 will understand that user has raised a request
to achieve Reverse Mode.
At Step 412: The microcontroller 107, 2013 will understand that user has raised a request
to achieve Neutral Mode.
At Step 413: The microcontroller 107, 2013 will understand that user has raised a request
to achieve Drive Mode.
At Steps 414-416: The microcontroller 107, 2013 may further output the determined
position as one or more of drive, reverse or neutral gear positions to a display through the bus
based on the ascertaining, the existence of the determined position or the combination of
positions.
For example, at Step 411, the microcontroller 107, 2013 will send out Data corresponding
Reverse mode to CAN Bus 106, 2012. Similarly, at Step 412, the microcontroller will send out
Data corresponding Neutral mode to CAN Bus 106, 2012. Similarly, at Step 412, the
microcontroller 107, 2013 will send out Data corresponding drive mode to CAN Bus 106, 2012.
At Steps 417: The microcontroller 107, 2013 will update the current status back to the
scheduler for further processing.
Once the detection of current gear position is completed, and the related information
received from Steps 408, 409 and 410 are communicated to the Microcontroller 107, 2013, an
indication is made. Specifically, a respective feedback indication is provided as the signal to
reflect the change in gear position on a display panel. A predefined CAN message is transmitted
14
through the CAN bus to a Vehicle integrated Master ECU with specific ID. An
acknowledgement message from the Master ECU may be received in response to the transmitted
message regarding the current gear position. The entire process of monitoring by the scheduler
iterates again to receive a new user input.
In an implementation, the ECU 107, 2013, as used herein, refers to any type of
computational circuit, such as, but not limited to, a microcontroller, a microprocessor, a complex
instruction set computing microprocessor, a reduced instruction set computing microprocessor, a
very long instruction word microprocessor, an explicitly parallel instruction computing
microprocessor, a graphics processor, a digital signal processor, or any other type of processing
circuit. The ECU 107, 2013may also include embedded controllers, such as generic or
programmable logic devices or arrays, application specific integrated circuits, single-chip
computers, smart cards, and the like.
In the case of implementation, an embodiment of the present invention may be
implemented by using hardware only, by using software and a necessary universal hardware
platform. The present invention may be implemented in the form of a procedure, function,
module, etc. that implements the functions or operations described above. Based on such
understandings, the technical solution of the present invention may be embodied in the form of
software. The software may be stored in a non-volatile or non-transitory storage medium, which
can be a compact disk read-only memory (CD-ROM), USB flash disk, or a removable hard disk.
For example, such execution may correspond to a simulation of the logical operations as
described herein. The software product may additionally or alternatively include a number of
instructions that enable a computing device to execute operations for configuring or
programming a digital logic apparatus in accordance with embodiments of the present invention.
While specific language has been used to describe the present subject matter, any
limitations arising on account thereto, are not intended. As would be apparent to a person in the
art, various working modifications may be made to the method in order to implement the
inventive concept as taught herein. The drawings and the foregoing description give examples of
embodiments. Those skilled in the art will appreciate that one or more of the described elements
may well be combined into a single functional element. Alternatively, certain elements may be
15
split into multiple functional elements. Elements from one embodiment may be added to another
embodiment.

We Claim:
1. An electronic contactless gear transmission-switch system (1010) for an automatic vehicle
transmission comprising:
a knob (101, 302) pivoted within a housing (201) above a detent profile, said knob (101,
302) defining a plurality of operable-positions upon actuation by a user;
a printed circuit board (300) comprising a plurality of sensors (303-307) to generate a
plurality of signals with respect to a plurality of positions of the knob (101, 302);
a Data Communication Bus (CAN) (106) for communicating signals from the electrical
circuit (300); and
a microcontroller (107) connected to the electrical circuit (300) through the CAN bus
(106) and configured for:
executing a scheduler configured for detecting change in the signal compared to
last captured signal, said scheduler detecting periodically in accordance with a first
predetermined time interval;
determining a position or a combination of positions traversed by the knob (101,
302) based on detecting the change in signal;
ascertaining an existence of the determined position or the combination of
positions for a second predetermined time interval; and
outputting the determined position as one or more of drive (D), reverse (R) or
neutral (N) gear positions to a display through the bus based on the ascertaining the
existence of the determined position or the combination of positions.
2. The system as claimed in claim 1, wherein the printed circuit board (300) is a comprises a
plurality of Hall elements (303-307) acting as the plurality of sensors.
3. The system as claimed in claim 1, wherein the detent profile is configured as a set of grooves
and peaks to correspond to the gear positions and additionally two intermediate gear positions.
4. The system as claimed in claim 1, wherein the knob (101, 302) corresponds to a toggle
switching element defined by a switching-step of a predetermined-size.
17
5. The system as claimed in claims 1 and 2, wherein the scheduler is configured for executing a
program counter-based checking of a sensor status as a part of detecting the signal change, said
counter defined by time period of 10 ms as the first predetermined time interval.
6. The system as claimed in claims 1 and 4, wherein determining the position or a combination
of positions corresponds to checking the combination of positions covered by the toggle
switching element comprised within the knob (101, 302).
7. The system as claimed in claims 1 and 3, wherein the outputting of the determined position
comprises outputting a Neutral position based on determining the position as the intermediate
position or the middle position.
8. The system as claimed in claims 1 and 3, wherein the outputting of the determined position
comprises outputting at least:
a Drive position based on determining the combination of position as a first intermediate
position, a first extreme position and a middle position; and
a Reverse position based on determining the combination of position as a second
intermediate position, a second extreme position, and the middle position.
9. The system as claimed in claim 1, wherein the second predetermined time interval corresponds
to a debounce time.
10. A method of operation of an electronic contactless gear transmission-switch system (1010)
for an automatic vehicle transmission comprising:
generating a plurality of signals, with respect to a plurality of positions of a knob (101,
302), by an electrical-circuit (300) comprising a plurality of sensors (303-307), said knob (101,
302) defining a plurality of operable-positions upon actuation by a user;
communicating signals from the electrical circuit (300) by a data communication bus
(CAN) (106) to a microcontroller (107);
18
performing by the microcontroller (107) connected to the electrical circuit (300) the steps
of:
executing (401, 402) a scheduler configured for detecting change in the signal
compared to last captured signal, said scheduler detecting periodically in accordance with
a first predetermined time interval;
determining (404) a position or a combination of positions traversed by the knob
based on detecting the change in signal;
ascertaining (408-413) an existence of the determined position or the combination
of positions for a second predetermined time interval; and
outputting (414 - 416) the determined position as one or more of drive, reverse or
neutral gear positions to a display through the bus based on the ascertaining the existence
of the determined position or the combination of positions.