DESC:FORM 2
The Patent Act 1970
(39 of 1970)
&
The Patent Rules, 2005

COMPLETE SPECIFICATION
(SEE SECTION 10 AND RULE 13)

TITLE OF THE INVENTION

AN AUTOMATIC GUIDED VEHICLE (AGV) FOR BIDIRECTIONAL MOTION CONTROL

Toyota Kirloskar Auto Parts Pvt Ltd
Plot No # 21, Bidadi Industrial Area,
Bidadi, Ramanagara District,
Bengaluru, Karnataka 562109, India
An Indian Company

The following specification particularly describes and ascertains the nature of this invention and the manner in which it is to be performed:

TECHNICAL FIELD
[001] The present invention relates to an automatic guided vehicle (AGV) for bidirectional motion control, more particularly related to a modular and flexible AGV for the bidirectional motion control.

BACKGROUND
[002] Generally, manufacturing industries continuously facing the challenge of cost reduction through various productivity improvement activities. Looking at the uncertain volumes, increasing labor cost, fluctuating demands, changes in customer needs, the manufacturing industries challenges not only limited to level up but also to sustain the current condition at industrial shop floor. Further, increase in the manpower cost year on year plays a significant role in increase in its product cost. Therefore, the manpower must be efficiently used for better productivity. Further, the manufacturing industries faces a major lose in man hour. The man hours mainly include conveyance or transfer of goods from one location to another location.
[003] Therefore, to overcome the man hour loses spent in part conveyance or transfer from one area to another area. The manufacturing industries uses Automation (replacing manpower work by automation) to achieve productivity by using Automated guided vehicles.
[004] The automated guided vehicle or automatic guided vehicle (AGV) is a portable robot that follows markers or wires in the floor, or uses vision, magnets, or lasers for navigation. They are most often used in industrial applications to move materials around a manufacturing facility or warehouse. The existing AGV are compatible to push and pull a dedicated dolly which are economically not viable. Therefore, there is a need for a flexible AGV which can accommodate both dedicated dolly’s pushing and multiple dolly’s pulling.
[005] Therefore, there exists a need for a low cost and efficient AGV for bidirectional movement without the need of gear box and multiple motors and there is also a need for AGV with reduced turning friction while taking a sharp turn.

OBJECTS
[006] The principal object of the embodiments herein is to disclose a modular and flexible AGV for the bidirectional motion control.
SUMMARY
[007] Accordingly, the embodiments herein provide an Automatic guided vehicle (AGV) for bidirectional motion control. The AGV includes a chassis, wherein the chassis includes a drive wheel mounted at a front end of the chassis and driven wheels mounted at a rear end of the chassis, wherein the driven wheels include at least one of a floating swivel wheel and a fixed wheel. Further, the AGV includes a drive control system, wherein the drive control system includes a drive motor and a steering motor coupled to the drive wheel. Further, the AGV includes a steering control system, wherein the steering control system includes a steering motor which is directly coupled with the driver control system to enable a steering control mechanism to move the AGV in forward and reverse direction. Further, the AGV includes a battery system, wherein the battery system includes at least one battery to supply power to the AGV.
[008] In an embodiment, wherein the driver motor coupled to the drive wheel configured to enable a drive motion to move the AGV in forward direction which in-tun pull the driven wheels in the forward direction.
[009] In an embodiment, the driver motor coupled to the drive wheel configured to enable a drive motion to move the AGV in reverse direction which in-tun push the driven wheels in the reverse direction by receiving power from the drive wheel.
[0010] In an embodiment, wherein the steering control mechanism includes a primary steering control rod, wherein one end of the primary steering control rod is connected to the drive control system and another end of the primary steering control rod is connected to a primary intermittent gear. Further, the steering control mechanism includes a secondary steering control rod, wherein one end of the secondary steering control rod is connected to the driven wheels and another end of the secondary steering control rod is connected to a secondary intermittent gear.
[0011] In an embodiment, the steering control mechanism to move the AGV in forward direction includes enabling, by the steering motor, to steer the AGV along a guide tape through a front side guide tape sensor, when the AGV moves in the forward direction; and.
[0012] In an embodiment, the steering control mechanism to move the AGV in reverse direction includes enabling, by the steering motor, to steer the drive wheel which in-turn steers the driven wheels in the reverse direction, when the steering motor receives a signal from a rear side guide tape sensor.
[0013] In an embodiment, the steering control mechanism includes enabling, by the steering motor, the primary steering control rod to push the primary intermittent gear and to rotate the primary intermittent gear in one direction, which in-turn rotates the secondary intermittent gear and pushes the secondary intermittent gear connected to the driven wheels to rotate the driven wheels in the opposite direction to make the AGV to take a turn.
[0014] In an embodiment, the primary intermittent gear and secondary intermittent gear are in meshed condition.
[0015] In an embodiment, the AGV is configured with a differential mechanism at the driven wheels to correct turning radius of the AGV, wherein the differential mechanism includes, when the AGV takes right turn, the drive wheel and the floating swivel wheel rotates at an angle X which in-turn enable the fixed wheel to rotate at an angle X-a towards left, thereby the floating swivel wheel aligns its degree to turning radius.
[0016] In an embodiment, the AGV is configured with a differential mechanism at the driven wheels to correct turning radius of the AGV, wherein the differential mechanism includes, when the AGV takes left turn, the drive wheel and the floating swivel wheel rotates at an angle Y which in-turn enable the fixed wheel to rotate at an angle Y+a towards right, thereby the floating swivel wheel aligns its degree to the turning radius.
[0017] In an embodiment, the AGV further comprises a fixed hook and an automatic hook.
[0018] These and other aspects of the example embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating example embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the example embodiments herein without departing from the spirit thereof, and the example embodiments herein include all such modifications.

BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Embodiments herein are illustrated in the accompanying drawings, throughout which like reference letters indicate corresponding parts in the various figures. The embodiments herein will be better understood from the following description with reference to the drawings, in which:
[0020] FIG.1 is a schematic diagram illustrating a bottom view of a chassis of an automated guided vehicle (AGV), wherein the chassis is mounted with a 3-wheel assembly, according to an embodiment as disclosed herein;
[0021] FIGS. 2a and 2b are schematic diagrams illustrating a drive control system of an automated guided vehicle (AGV), wherein the FIG.2a indicates forward movement of the AGV and the FIG. 2b indicates a revers movement of the AG, according to an embodiment as disclosed herein;
[0022] FIG. 3a and 3b are schematic diagrams illustrating a steering control system, wherein the FIG. 3a illustrates a steering mechanism of the AGV for taking right turn, wherein the FIG. 3b illustrates the steering mechanism of the AGV for taking left turn, according to an embodiment as disclosed herein;
[0023] FIG. 4a and 4b are schematic diagrams illustrating a differential mechanism of the AGV, according to an embodiment as disclosed herein; and
[0024] FIG. 5a and 5b are schematic diagrams illustrating a fixed hook and an automatic hook of the AGV, according to an embodiment as disclosed herein.

DETAILED DESCRIPTION OF THE DRAWINGS
[0025] The example embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted to not unnecessarily obscure the embodiments herein. The description herein is intended merely to facilitate an understanding of ways in which the example embodiments herein can be practiced and to further enable those of skill in the art to practice the example embodiments herein. Accordingly, this disclosure should not be construed as limiting the scope of the example embodiments herein.
[0026] The embodiments herein achieve an Automatic guided vehicle (AGV) for bidirectional motion control. The AGV includes a chassis, wherein the chassis includes a drive wheel mounted at a front end of the chassis and driven wheels mounted at a rear end of the chassis, wherein the driven wheels include at least one of a floating swivel wheel and a fixed wheel. Further, the AGV includes a drive control system, wherein the drive control system includes a drive motor and a steering motor coupled to the drive wheel. Further, the AGV includes a steering control system, wherein the steering control system includes a steering motor which is directly coupled with the driver control system to enable a steering control mechanism to move the AGV in forward and reverse direction. Further, the AGV includes a battery system, wherein the battery system includes at least one battery to supply power to the AGV.
[0027] In an embodiment, the driver motor coupled to the drive wheel configured to enable a drive motion to move the AGV in forward direction which in-tun pull the driven wheels in the forward direction. In another embodiment, the driver motor coupled to the drive wheel configured to enable a drive motion to move the AGV in reverse direction which in-tun push the driven wheels in the reverse direction by receiving power from the drive wheel.
[0028] In an embodiment, the steering control mechanism includes a primary steering control rod, wherein one end of the primary steering control rod is connected to the drive control system and another end of the primary steering control rod is connected to a primary intermittent gear. Further, the steering control mechanism includes a secondary steering control rod, wherein one end of the secondary steering control rod is connected to the driven wheels and another end of the secondary steering control rod is connected to a secondary intermittent gear.
[0029] In an embodiment, the steering control mechanism to move the AGV in forward direction includes enabling, by the steering motor, to steer the AGV along a guide tape through a front side guide tape sensor, when the AGV moves in the forward direction; and.
[0030] In an embodiment, the steering control mechanism to move the AGV in reverse direction includes enabling, by the steering motor, to steer the drive wheel which in-turn steers the driven wheels in the reverse direction, when the steering motor receives a signal from a rear side guide tape sensor.
[0031] In an embodiment, the steering control mechanism includes enabling, by the steering motor, the primary steering control rod to push the primary intermittent gear and to rotate the primary intermittent gear in one direction, which in-turn rotates the secondary intermittent gear and pushes the secondary intermittent gear connected to the driven wheels to rotate the driven wheels in the opposite direction to make the AGV to take a turn. In an embodiment, the primary intermittent gear and secondary intermittent gear are in meshed condition.
[0032] In an embodiment, the AGV is configured with a differential mechanism at the driven wheels to correct turning radius of the AGV, when the AGV takes right turn. The drive wheel and the floating swivel wheel rotates at an angle X which in-turn enable the fixed wheel to rotate at an angle X-a towards left, thereby the floating swivel wheel aligns its degree to turning radius.
[0033] In an embodiment, the AGV is configured with a differential mechanism at the driven wheels to correct turning radius of the AGV, when the AGV takes left turn. The drive wheel and the floating swivel wheel rotates at an angle Y which in-turn enable the fixed wheel to rotate at an angle Y+a towards right, thereby the floating swivel wheel aligns its degree to the turning radius.
[0034] Referring now to the drawings, and more particularly to FIGS. 1 through 4b, where similar reference characters denote corresponding features consistently throughout the figures, there are shown example embodiments.
[0035] FIG.1 is a schematic diagram illustrating a bottom view of a chassis 101 of an automated guided vehicle (AGV) 100, wherein the chassis 101 is mounted with a 3-wheel assembly (i.e., a drive wheel 106 and driven wheels (i.e., floating swivel wheel 102 and fixed wheel 104)), according to an embodiment as disclosed herein.
[0036] The AGV 100 includes a monocoque chassis where all the AGV 100 elements are mounted on a single frame (i.e., Chassis frame). The chassis 101 includes a drive wheel mounted at a front end of the chassis 101 and driven wheels mounted at a rear end of the chassis 101, wherein the driven wheels 102, 104 include at least one of a floating swivel wheel and a fixed wheel. Further, the chassis 101 includes a drive control system, wherein the drive control system includes a drive motor coupled to the drive wheel 106. Further, the chassis 101 includes a steering control system, wherein the steering control system includes a steering motor which is directly coupled with the driver control system to enable a steering control mechanism to move the AGV 100 in forward and reverse direction. Further, the chassis 101 includes a battery system (not shown), wherein the battery system includes at least one battery to supply power to the AGV 100. The chassis 101 has a flexible feature, wherein the chassis 101 can accommodate dual/double batteries for long run of the AGV 100.
[0037] The chassis 101 of the AGV 100 is mounted/attached with the 3-wheel assembly or 3-wheel set at the bottom side of the chassis 101 on which the entire AGV 100 is balanced. The 3-wheel balance eliminates the need of shock absorbers and the AGV 100 can balance on its own irrespective of undulations on a floor. The 3-wheel assembly mechanism avoid the AGV 100 to run in inclined manner and helps in smooth running of the AGV 100 while taking a turn without adding turning friction resistance to the AGV 100 motion.
[0038] FIGS. 2a and 2b are schematic diagrams illustrating a drive control system of the AGV 100, wherein the FIG.2a indicates forward movement of the AGV 100 and the FIG. 2b indicates a revers movement of the AGV 100, according to an embodiment as disclosed herein. In an embodiment, the drive control system includes a single drive motor 202 which is coupled to the drive wheel 106 at front side of the chassis 101 to enable a forward motion of the AGV 100. Further, the same drive motor 106 can be used to drive the rear driven wheels 102, 104 when the AGV 100 moves in reverse direction without any additional actuator (motor) for reverse direction motion. FIG. 2a illustrates a forward motion of the AGV 100, wherein the AGV 100 moves in forward direction, the drive motor 106 which is connected to the front drive wheel 106 enables a drive motion, during which the rear side driven wheel 102, 104 move along with the drive wheel 106. FIG. 2b illustrates reverse motion of the AGV 100, wherein the rear driven wheels 102, 104 get the power from the front side drive wheel 106 which is attached with the drive motor 106 to move in the reverse direction.
[0039] FIG. 3a and 3b are schematic diagrams illustrating a steering control system, wherein the FIG. 3a illustrates a steering mechanism of the AGV 100 for taking right turn, wherein the FIG. 3b illustrates the steering mechanism of the AGV 100 for taking left turn, according to an embodiment as disclosed herein.
[0040] The embodiments herein provide the steering control system built with Steering Control Rod (SCR) mechanism. Wherein both the forward and the reverse direction movement steering is controlled by a single steering motor 302. The SCR eliminates requirement of an additional actuator (motor) needed for each direction movement (i.e., forward and reverse) steering control. The single steering motor 302 coupled to the drive control system and the steering control system using SCR carries out forward movement steering control and Reverse movement steering control of the AGV 100.
[0041] Forward movement steering control: When the AGV 100 moves in forward direction, the steering control motor/steering motor 302 which is directly fixed to the drive wheel 106 can steer the AGV 100 along the guide tape 204 through a front side guide tape sensor.
[0042] Reverse movement steering control: When the AGV 100 moves in the reverse direction, a rear side guide tape sensor sends signal to the steering motor 302 connected to the drive wheel 106. Further, the steering motor 302 steers the front side drive control system which in-turn steers the rear side driven wheels 102, 104 using the SCR mechanism.
[0043] The Steering control rod mechanism consists of 2 Steering Control Rods (SCR#) and 2 intermittent gears (Gear#). The primary SCR#1 is connected to the front side drive control system (drive wheel 106 and steering motor 302) at one end and Primary intermittent Gear#1 at the other end. The secondary SCR#2 is connected to rear side driven wheels 102, 104 at one end and secondary intermittent Gear#2 at the other end.
[0044] Whenever the steering motor 302 rotates the drive system, the SCR#1 pushes the Gear #1 and the Gear #1 rotates in one direction, as the Gear #1 and the Gear #2 are in meshed condition always, in turn the Gear #2 rotates and pushes the SCR#2 which is connected to rear driven wheels 102, 104. Thus, making rear driven wheels 102, 104 to rotate in opposite direction and enabling the AGV 100 to take a turn. This SCR mechanism helps the AGV 100 to stick to its path firmly and follow the same, even when there is a need of minimum turning radius. The turning radius is a result of both front drive wheel 106 and the rear driven wheels 102, 104 turning angle.
[0045] FIG. 3a depicts the steering control rod mechanism of the AGV 100 to perform a right turn, wherein the front drive wheel 106 coupled with the drive motor M1 202 and the steering motor M2 302. In an embodiment, when the front drive wheel 106 of the AGV 100 takes a right turn, the rear driven wheels 102, 104 turn to opposite direction i.e., left turn through the SCR and intermittent gears.
[0046] Similarly, FIG.3 depicts the steering control rod mechanism of the AGV 100 to perform a left turn, wherein the front drive wheel 106 coupled with the drive motor M1 202 and the steering motor M2 302. In an embodiment, when the front drive wheel 106 of the AGV 100 takes a left turn, the rear driven wheels 102, 104 turn to opposite direction i.e., right turn through SCR and intermittent gear mechanism.
[0047] The embodiments herein control the AGV 100 steering motion with single actuator (motor) 302, which controls both side steering with links and gears. The embodiments herein reduce the number of actuators (motors) required to build a 2-way AGV 100 and so to ensure track or guide adherence of the AGV 100 which will enhance the AGV capability to take sharp turns. Further, this will also avoid the guide tape damage which may occur due to drive and driven wheels movement on the tape.
[0048] FIG. 4a and 4b are schematic diagrams illustrating a differential mechanism of the AGV, according to an embodiment as disclosed herein.
[0049] The differential mechanism is used to correct the AGV 100 turning radius whenever 2 wheels are used. The AGV 100 features a unique combination of rear driven wheels design which can provide the differential mechanism without a differential gear box. The AGV 100 has a free rotating swivel wheel 102 at the rear side, which does the function of differential mechanism and helps the rear wheels 102,104 of the AGV 100 to automatically align to turning radius.
[0050] FIG. 4a depicts a differential mechanism of the AGV 100 for taking the right turn. Whenever the AGV 100 takes the right turn at an angle “X”, the rear side fixed wheel 104 rotates minimum at an angle “X- a” and the rear side floating swivel wheel 102 rotates maximum at an angle of X degree. Further, the floating swivel wheel 106 automatically align its degree to the turning radius thus achieving the differential mechanism without any actuator or gear box. Thus, the AGV 100 can takes the right turn as shown in FIG. 4a.
[0051] Similarly, FIG. 4b depicts a differential mechanism of AGV 100 for taking a left turn. Whenever an AGV 100 takes a left turn at angle “Y”, the rear side fixed wheel 104 rotates at an angle “Y+ a” and the floating swivel wheel 102 rotates at an angle Y. Further, the floating swivel wheel 102 automatically align its degree to the turning radius thus achieving the differential mechanism without any actuator or gear box. Thus, the AGV 100 can takes the left turn as shown in FIG. 4a.
[0052] FIG. 5a and 5b are schematic diagrams illustrating the fixed hook and the automatic hook of the AGV 100, according to an embodiment as disclosed herein.
[0053] The fixed hook and the automatic hook enhance the flexibility of the AGV 100. The automatic hook can go up and down making the AGV 100 flexible to use in different application. Further, modular design with auto hook feature enables the AGV 100 to automatically park an associated dolly along with pushing the dolly.
[0054] All equivalent relationships to those illustrated in the drawings and described in the application are intended to be encompassed by the present invention. The examples used to illustrate the embodiments of the present invention, in no way limit the applicability of the present invention to them. It is to be noted that those with ordinary skill in the art will appreciate that various modifications and alternatives to the details could be developed in the light of the overall teachings of the disclosure, without departing from the scope of the invention
[0055] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
,CLAIMS:We claim
1. An Automatic guided vehicle (AGV) for bidirectional motion control, the AGV comprises:
a chassis, wherein the chassis includes a drive wheel mounted at a front end of the chassis and driven wheels mounted at a rear end of the chassis, wherein the driven wheels include at least one of a floating swivel wheel and a fixed wheel;
a drive control system, wherein the drive control system includes a drive motor coupled to the drive wheel;
a steering control system, wherein the steering control system includes a steering motor which is directly coupled with the driver control system to enable a steering control mechanism to move the AGV in forward and reverse direction;
a battery system, wherein the battery system includes at least one battery to supply power to the AGV.
2. The AGV as claimed in claim 1, wherein the driver motor coupled to the drive wheel configured to:
enable a drive motion to move the AGV in forward direction which in-tun pull the driven wheels in the forward direction; and
enable a drive motion to move the AGV in reverse direction which in-tun push the driven wheels in the reverse direction by receiving power from the drive wheel.
3. The AGV as claimed in claim 1, wherein the steering control mechanism includes:
a primary steering control rod, wherein one end of the primary steering control rod is connected to the drive control system and another end of the primary steering control rod is connected to a primary intermittent gear; and
a secondary steering control rod, wherein one end of the secondary steering control rod is connected to the driven wheels and another end of the secondary steering control rod is connected to a secondary intermittent gear.
4. The steering control mechanism as claimed in claim 3, wherein the steering control mechanism to move the AGV in forward direction and reverse direction includes:
enabling, by the steering motor, to steer the AGV along a guide tape through a front side guide tape sensor, when the AGV moves in the forward direction; and.
enabling, by the steering motor, to steer the drive wheel which in-turn steers the driven wheels in the reverse direction, when the steering motor receives a signal from a rear side guide tape sensor.
5. The steering control mechanism as claimed in claim 3, wherein the steering control mechanism includes:
enabling, by the steering motor, the primary steering control rod to push the primary intermittent gear and to rotate the primary intermittent gear in one direction, which in-turn rotates the secondary intermittent gear and pushes the secondary intermittent gear connected to the driven wheels to rotate the driven wheels in the opposite direction to make the AGV to take a turn.
6. The steering control rod mechanism as claimed in claim 5, wherein the primary intermittent gear and secondary intermittent gear are in meshed condition.
7. The AGV as claimed in claim 1, wherein the AGV is configured with a differential mechanism at the driven wheels to correct turning radius of the AGV, wherein the differential mechanism includes:
when the AGV takes right turn, the drive wheel and the floating swivel wheel rotates at an angle X which in-turn enable the fixed wheel to rotate at an angle X-a towards left, thereby the floating swivel wheel aligns its degree to turning radius; and
when the AGV takes left turn, the drive wheel and the floating swivel wheel rotates at an angle Y which in-turn enable the fixed wheel to rotate at an angle Y+a towards right, thereby the floating swivel wheel aligns its degree to the turning radius.
8. The AGV as claimed in claim 1, wherein the AGV further comprises a fixed hook and an automatic hook.