ENDLESS TRACK
20180021947 ยท 2018-01-25
Inventors
Cpc classification
B25J5/005
PERFORMING OPERATIONS; TRANSPORTING
Y10S901/31
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B25J9/08
PERFORMING OPERATIONS; TRANSPORTING
B62D55/075
PERFORMING OPERATIONS; TRANSPORTING
B62D55/244
PERFORMING OPERATIONS; TRANSPORTING
Y10S901/01
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B62D55/26
PERFORMING OPERATIONS; TRANSPORTING
International classification
B25J9/08
PERFORMING OPERATIONS; TRANSPORTING
B25J5/00
PERFORMING OPERATIONS; TRANSPORTING
B62D55/075
PERFORMING OPERATIONS; TRANSPORTING
B62D55/24
PERFORMING OPERATIONS; TRANSPORTING
B25J11/00
PERFORMING OPERATIONS; TRANSPORTING
Abstract
An endless track is for use with a mobile robot and includes a belt, a plurality of chamfered cleats, a plurality of holes and a dual v-guide. The belt has an inner surface and an outer surface. The plurality of chamfered cleats, each have a contact surface. The chamfered cleats are attached to the outer surface defining an attachment area, and the contact surface is shaped such that when the track is laid on a flat solid surface, each chamfered cleat contacts the flat solid surface with less area than the attachment area. The plurality of holes in the belt are disposed between the chamfered cleats and are shaped to allow teeth of a drive sprocket pulley to pass through and to engage the belt for transmitting force from the sprocket pulley to the belt. The dual v-guide includes two elongate, parallel protrusions which are spaced laterally from each other and are attached to the inner surface.
Claims
1. An endless track for use with a mobile robot having a drive sprocket with teeth, comprising: a belt having an inner surface and an outer surface; a plurality of chamfered cleats each having a contact surface, the chamfered cleats being attached to the outer surface defining an attachment area, and the contact surface shaped such that when the endless track is laid on a flat solid surface, each chamfered cleat contacts the flat solid surface with less area than the attachment area; a plurality of holes in the endless track, disposed between the chamfered cleats and shaped to allow teeth of the drive sprocket to pass through and to engage the belt for transmitting force from the drive sprocket to the belt; and a dual v-guide comprising two elongate, parallel protrusions which are spaced laterally from each other, and are attached to the inner surface.
2. The endless track according to claim 1 wherein each of the plurality of chamfered cleats has a substantially rectangular cross section in a plane perpendicular to the lateral direction to the endless track.
3. The endless track according to claim 2 further comprising a fillet where each of the plurality of chamfered cleats attaches to the outer surface.
4. The endless track according to claim 3 wherein each of the plurality of chamfered cleats is integrally formed with the belt.
5. The endless track according to claim 4 wherein each of the plurality of chamfered cleats has a rubber cover.
6. The endless track according to claim 5 wherein the holes are substantially rectangular.
7. The endless track according to claim 1 wherein the two elongate parallel protrusions extend around the belt.
8. The endless track according to claim 1 wherein the two elongate parallel protrusions of dual v-guide are first two elongate parallel protrusions, and further including at least a second two elongate parallel protrusions.
9. The endless track according to claim 8 wherein the first and second two elongate parallel protrusions have rounded edges.
10. The endless track according to claim 9 wherein the first and at least a second two elongate parallel protrusions are spaced longitudinally such that the drive sprocket, in operation, is always contacted by at least a portion of the first and second two elongate parallel protrusions.
11. The endless track according to claim 1 wherein the belt is made of nylon.
12. The endless track according to claim 11 wherein the dual v-guide is made of polyurethane.
13. The endless track according to claim 12 wherein the plurality of chamfered cleats each comprise a material selected from the group consisting of rubber and polyurethane.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0043] The mobile robot will now be described by way of example only, with reference to the accompanying drawings, in which:
[0044]
[0045]
[0046]
[0047]
[0048]
[0049]
[0050]
[0051]
[0052]
[0053]
[0054]
[0055]
[0056]
[0057]
[0058]
[0059]
[0060]
[0061]
[0062]
[0063]
[0064]
[0065]
[0066]
[0067]
[0068]
[0069]
[0070]
[0071]
[0072]
[0073]
[0074]
[0075]
[0076]
[0077]
[0078]
[0079]
[0080]
[0081]
[0082]
[0083]
[0084]
[0085]
[0086]
[0087]
DETAILED DESCRIPTION
[0088] The systems described herein are directed, in general, to modular mobile robots, to interchangeable features for use therein, to a tooling arm for use therewith, to an endless track for use therewith and to a flexible tail. Although embodiments of the mobile robot are disclosed herein, the disclosed embodiments are merely exemplary. Furthermore, the Figures are not drawn to scale and some features may be exaggerated or minimized to show details of particular features while related elements may have been eliminated to prevent obscuring novel aspects. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting but merely as a basis for the claims and as a representative basis for enabling someone skilled in the art to a mobile robot.
[0089] Referring to
[0090] Mobile robots that have interchangeable components are particularly useful for a user that has a big fleet of mobile robots. By having modules that are useable in different sized mobile robots it keeps in reserve a series of different components that are useable in different robots, thus making it easier to keep the fleet running. In many fleets there are multiple sizes of mobile robots. By way of example as shown in
[0091] Components that may be interchangeable between robots of two or more sizes are the control unit, communication components, electronics components, power components, external sensors, internal sensors, cameras and weaponry. The communication components and a main processor may form part of a self-contained core module which may be interchangeable between different sized robots. Power and data distribution system may form part of a self-contained head module which may be interchangeable between different sized robots. A self-contained power module may be downwardly compatible with different robots meaning that if it is sized for a particular size of chassis it will work with that sized chassis and smaller chassis. In contrast external components such as a large gripper arm, small gripper arm and PTZ arm are upwardly compatible meaning that if the arm is sized for a particular size of chassis it will work with that sized chassis and larger chassis. As well, software programs that control specific tasks may be interchangeable between different sized robots. For example tasks such as auto navigation and auto grasping of tools from a tool rack would be interchangeable. As well, software that controls the driving function and software that controls the PTZ could be interchangeable. Software that controls the sensors, software for relay control, software for power distributions, software that controls weaponry where the weaponry is interchangeable and software for video selection could each be interchangeable. However, software that controls the flipper, software that controls the gripper arm and software that controls the PTZ arm would be specific to the particular size of those components.
[0092] It will be appreciated by those skilled in the art that not all of the components or modules may be interchangeable between different sized robots. Specifically the modules associated with the chassis are not interchangeable between different sized robots. More specifically the self-contained head, core, and power modules (described in more detail below) would be interchangeable. Accordingly, the components associated with the chassis, the traction, the transmissions and the power would not be interchangeable. Components such as the gripper arm, PTZ (pan, tilt and zoom) arm and tools could be upwardly compatible in that the components designed for a smaller robot could be used on a larger robot; however it is unlikely that the smaller components would provide the functionality of the larger robot.
[0093] The core module, the head module and the power module are described as being self-contained since each is contained in a housing such that it can be easily removed and replaced. The core module, the head module and the power module are complete modules, which are self-contained modules that can be easily removed and replaced in a particular robot or used in other mobile robots. More specifically in one embodiment the core module has processor, communication interface card, wireless transceiver for two-way data and audio, one-way video, DC-DC converter inside. The core module is the brain of the robot. It accepts task commands from the control unit and analyses and translates the task commands then issue to different modules and receives feedbacks from these modules via its multiple serial ports. It also provides Ethernet, USB, RS232, RS485, RS422 and VGA interface to users so the users can develop their own software to control the robot. The power module integrates high capacity Li-Polymer battery, DC-DC converter, and control relays. The output interface connector on the power module includes the power switch pins, the power relay coil pins, and the 12 VDC, 24 VDC, and 37 VDC output pins. The power outputs are isolated from the other modules by the power switch and power relay contacts, which means only after the power switch and power relay are on (manually or remotely), the 12 VDC, 24 VDC and 37 VDC will be output to the external. The head module in the robot accepts power input from the power module and control signal input/output from the core module and distributes power to all the different modules, including by way of example the drive transmission module, flipper module, gripper arm module, PTZ arm module, and upgrade module. The power and signal distribution is realized by hard wire inside the head module to minimize any extra processing delay. The head module also manages the cameras, lights(visible and InfraRed), picture-in-picture display, the platform disruptor and laser control, and the relay control.
[0094] As well, it is useful to have a mobile robot wherein the functionality of the robot can be changed by changing a component or a module. For example arms of different sizes may be attachable to the same robot or different end effectors may be attached to the same or different arms.
[0095] One embodiment of the mobile robot described herein is constructed of a series of modules. This makes it easy to change from a track robot to a wheel robot or from a long track robot to a short track robot. As well, when a robot is in need of repair, the robot is designed such that a module can be removed and a replacement module may be easily installed.
[0096] Mobile robot 10 as shown in
[0097] The drive system components are attachable to the chassis 12. The drive system components include drive traction modules and drive transmission modules. Referring to
[0098] The power module 20 includes battery and multiple voltage DC-DC converters, and provides all the voltages and the power for the entire robot. The core module 22 includes the main processor and communication system, and manages the communication to the control unit for all the modules. It is operably connected to the other modules. The core module receives commands from the control unit and then commands the other modules. The core module controls the motion of the robot through the drive transmission module 18 and the flipper transmission module 19. The control unit (not shown) is typically situated remote from the robot. The control unit may be an operator control unit or an autonomously controlled unit. The control unit might also include a hybrid communication system that includes a relay unit.
[0099] The head module 24 is a power, data and communication distribution module, and an interface module to external sensors. The head module is operably connected to the power module 20 and to the core module 22. As well, it is operably connected to the other modules. The head module 24 distributes the power from the power module 20 and it distributes the commands from the core module 22. The head module 24 controls all aspects of the mobile robot. For example, it passes the power and operating instructions to the drive transmission module 18 and the flipper transmission module 19, as well, through another channel it transmits power and operating instructions to other components such as the gripper arm, the PTZ arm, fiber optical components. The head module 24 also distributes power such as 12V and operating instructions to internal and external sensors components and any weaponry. In the embodiment shown herein the head module 24 is configured to interface with up to two sensors with a serial communication interface. In addition, the head module 24 controls the laser pointer, disruptor and relay outputs 69 and 70 on the platform. Mounted with the head module 24 are a camera 71 and two visible 72 and IR 73 lights. The head module 24 is provided with a plurality of ports. For example there is provided a PTZ arm port 74, a gripper arm port 75, a battery charger port 30, a Wi-Fi port 32. PTZ arm port 74 and gripper arm port 75 provide the power supply, the communication and the video signals to the respective arm. The arm function is defined in its independent control box. The head module 24 also may include specific internal sensors such as a temperature sensor, a compass, an inclinometer and a battery power sensor. As well, the head module may also have sensors which may include gas sensor and environmental sensors such as chemical, biological, nuclear and explosive (CBRNE) sensors. Alternatively the CBRNE sensors may be in a separate module that is attachable to the chassis or to one of the gripper arms as a payload. These sensors may be either internal or external.
[0100] In addition, the head module includes software to control the sensors, software for relay control, software for power distribution, software for data distribution and software for video selection.
[0101] The chassis 12 is generally a box 34 with a hinged lid 36. A pair of rails 38 is attached to the outside of the chassis. The rails 38 facilitate the attachment of the components such as the gripper arm.
[0102] In the embodiment shown herein some of the modules are mechatronics modules in that they have the electronics and mechanical parts integrated. For example, the flipper transmission module 19 has motor, gear head, encoder, angular position sensor, brake, servo motor driver, transmission gear pairs, cam, mechanical structure, etc. The large gripper arm module 28 has motors, gear heads, encoders, angular position sensors, payload interface, weapon control interface, and the mechanical structure, links, and gripper fingers integrated. The PTZ arm 26 has a motor, motor driver and power conditioning.
[0103] In the embodiment herein, the core module 22 has a plurality of serial ports, and can be configured to multiple serial communication protocol standards.
[0104] Among them, serial ports in the core module are connected to the head module 24, and from there connected to different modules. In the embodiment herein the serial ports from the head module are connected to: the drive transmission and flipper transmission modules 18 and 19, the gripper arm 28, the PTZ arm 26, the fiber optical module 44. In addition other modules or components may also be connected to the serial ports. All the communications are initiated by the core module 22. Only the core module 22 can talk to different modules and the modules will not talk to each other directly. However, the head module passes the information or talk to the other components. The core module routes the communication through the head module 24. It will be appreciated by those skilled in the art that the number of ports in the core module 22 and the head module 24 may vary depending on the specific use and specifications for the mobile robot.
[0105] The upgrade module 46 includes fiber optic spool and cable and additional sensors. The upgrade module is only for use in the large and medium mobile robots. The fiber optic cable is connected to the control unit and is to communicate with the core module 22.
[0106] It will be appreciated by those skilled in the art that embodiment of the modular mobile robot shown and described herein provides the user with a number of options in regard to the configuration of the robot and the components attached thereto. For example the robot has three basic traction configurations; namely the long tack traction module 14 and flipper modules 16 attached to the chassis, as shown in
[0107] As well the embodiment of the modular mobile robot shown herein allows for the reconfiguring of the arm and payloads for specific missions. For example, referring to
[0108] A number of modules may be interchangeable between different sized mobile robots.
[0109] Referring to
[0110] The embodiments of the modular mobile robot may also include modules that may control specific functions. For example an auto navigation module which is operably connected to the core module can control the motion of the robot. An auto navigation module includes a processor and a plurality of sensors, such as IMU (inertia measurement unit), inclinometer, gyro, and LIDAR (light detection and ranging). This module will calculate the path based on the sensor feedback and send the motion commands to the core module. There may also be a module for automatically controlling specific functions of the gripper arm such as an automatic stow motion or an automatic deploy function, as well as automatically grasping and changing tools from the tool box. This auto grasping module includes a processor and a plurality of sensors such as force and tactile sensors.
[0111] Referring to
[0112] Referring to
[0113] Drive system 82 may be a motor and gear head assembly. The drive system 82 is fixedly mounted on an upper mounting plate 94 which is fixedly attached to the housing 88. Lead screw and nut assembly 84 includes a lead screw 100, a nut 102 (as best seen on
[0114] The scoop assembly 86 includes a pair of scoops 106, a pair of links 110 and a shuttle 108. Each scoop 106 is pivotally attached to a shuttle 108. Each link 110 is pivotally attached at one end thereof to a scoop 106 and at the other end thereof to a bracket 112. Bracket 112 is attached to the bottom end of the lead screw 100. Thus as the lead screw moves up and down the bracket 112 moved up and down. Shuttle 108 has a pair of generally vertical slots 114 formed therein. A post 116 extends outwardly from the link 110 where the link is pivotally attached to the bracket 112. Post 116 slidingly engages the slot 114 in shuttle 108.The scooping assembly 86 acts as a four bar link mechanism wherein the slider is the lead screw 100; the coupler link is link 110; the slide link is the scoop 106; and the frame is the shuttle 108.
[0115] Housing 88 is provided with a block 118 which is adapted to engage stopper 120 extending outwardly from shuttle 108 as best seen in
[0116]
[0117] A sampling sensor 148 may be mounted inside scoop 106 to measure if sample is collected. A distance sensor may be fixedly mounted on the shuttle 108 to detect the distance between scoop 106 and the ground.
[0118] Referring to
[0119] In some embodiments, the cleats 136 are attached to the outer surface 134 defining an attachment area, and a contact surface 138 which has a smaller surface area than the attachment area. In other words, the cleats 136 may be chamfered such that when the track is laid on a flat solid surface, each chamfered cleat 136 contacts the flat solid surface with less area than the attachment area. This reduces the friction and vibration of the track during turning and driving. In order to maintain the traction provided by using an endless track, while still reducing friction and vibration by using chamfered cleats 136, the cleats 136 may be chamfered or rounded only on edges which are substantially parallel to the longitudinal direction of motion of the track 130. For example, for cleats 136 are substantially rectangular prism-shaped before chamfering during manufacturing, each of the plurality of chamfered cleats 136 remains substantially rectangular when viewed in a lateral direction to the track. For example, as shown in
[0120] In some embodiments of the endless track, a dual v-guide 142 is attached to or possibly integrally formed with the inner surface 132 of the belt 131. With reference to
[0121] In some embodiments, the track 130 may have holes 144 in between the cleats 136, as shown in
[0122] In this embodiment belt 131 is a TTA-1500 belt manufactured from NITTA Corporation. Belt 131 has a 2.4 mm thickness. Its major structure is composed of Nylon core and Nylon fabrics. Its properties includes: tensile strength450 N/mm, elongation at break25%, standard tension1.0%, working load at 1%22.5 N/mm, temperature range20 to 80 C., coefficient of friction (steel)0.2 to 0.3.
[0123] In embodiments of the endless track with a continuous dual v-guide 142, each protrusion may be shaped such that it increases the second moment of area of the track to provide enhanced stiffness with very little additional mass. In such embodiments, it will be appreciated that tall and slender protrusions provide the highest gain in stiffness per additional mass. In embodiments the belt 131 comprises holes 144 to engaged sprocket teeth 148, the dual v-guide 142 may reinforce the track to compensate for the reduced stiffness due to the holes 144. Further, chamfered cleats 136 may be additionally included and positioned to reinforce the areas of the track having holes 144. In such embodiments, in addition to their primary functions, the dual v-guide 142 provides longitudinal bending stiffness to the track and the cleats 136 provide lateral bending stiffness to the track.
[0124] Track 130 is composed of belt 131, rubber cover with cleats 136, and V-guide 142.
[0125] As shown in
[0126] The flexible tail 150 may be made of any material, be of any length, and be of any cross sectional shape such that it can support itself as a cantilever beam. Usually, the determination of the flexible tail length (L) depends on: (1) the structure parameters of the platform such as the center distance (C) between the front and rear pulleys/wheels and the pulley/wheel diameter (D); (2) the obstacle height (H) to be surmounted, or stairs span (L) to be climbed. For example, if the design is required to climb the stairs with L span, the flexible tail length L can be obtained based on the following equation,
In non-limiting examples, the tail 150 may be made of any material which has sufficient strength, stiffness, and flexibility. It could be metal material such as alloy, spring steel, etc; or non-metal material such as fiber glass or rubber, and it may have a rectangular, circle, or elliptic cross section. For example, in the embodiment shown in
[0127] The flexible tail 150 provides a number of advantages for mobile robots. For example, when it is deployed or its deployment direction is changed by rotating it, it can be done in a rapid manner because of its ability to absorb energy by deforming. Thus, the flexible tail 150 will have a much lower chance of breaking itself or the robot it is attached to when it impacts a solid surface. In a similar scenario, if the flexible tail 150 is deployed ahead of a robot while the robot is driving forward, if the tail 150 contacts a solid object (e.g. a wall or a large rock), it will not transfer the impact energy directly to the robot, and will instead deform to absorb it. If the robot is dropped or it falls, the flexible tail 150 may absorb some of the impact energy thus cushioning the robot's fall. Further, the flexible tail 150 allows the centre of mass of a robot to change, and is compliant to uneven terrain when resting upon it, thus granting the robot a more stable stance on such uneven terrain.
[0128] It is noted that, when deployed in certain configurations (such as that shown in
[0129] While the mobile robot shown in the figures is a robot, it will be understood by one skilled in the art that the mobile robot comprising the endless track and/or the flexible tail described herein may be any number of robots. In non-limiting examples, the mobile robot may be a robot; a construction robot such as a backhoe, bulldozer, or crane; a farm robot such as a harvester or tractor; a military robot such as a tank; or a robot for moving on snow.
[0130] Generally speaking, the systems described herein are directed to modular mobile robots, interchangeable features for use therein, a tooling arm for use therewith and an endless track for use therewith. The Figures are not to scale and some features may be exaggerated or minimized to show details of particular elements while related elements may have been eliminated to prevent obscuring novel aspects. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting but merely as a basis for the claims. For purposes of teaching and not limitation, the illustrated embodiments are directed to a modular mobile robots, interchangeable features for use therein, a tooling arm for use therewith and an endless track for use therewith.
[0131] As used herein, the terms having, comprises, comprising, includes and including are to be construed as being inclusive and open ended, and not exclusive. Specifically, when used in this specification including claims, the terms comprises, comprising, includes and including and variations thereof mean the specified features, steps or components are included. These terms are not to be interpreted to exclude the presence of other features, steps or components.
[0132] As used herein, the terms substantially, about and approximately, when used in conjunction with ranges of dimensions, compositions of mixtures or other physical properties or characteristics, is meant to cover slight variations that may exist in the upper and lower limits of the ranges of dimensions so as to not exclude embodiments where on average most of the dimensions are satisfied but where statistically dimensions may exist outside this region.
[0133] As used herein, the coordinating conjunction and/or is meant to be a selection between a logical disjunction and a logical conjunction of the adjacent words, phrases, or clauses. Specifically, the phrase X and/or Y is meant to be interpreted as one or both of X and Y wherein X and Y are any word, phrase, or clause.
[0134] As used herein the term operably connected to means that the two elements may be directly connected or indirectly connected that is they are connected through other elements.
[0135] As used herein, the word longitudinal, when used in a context relating to a direction of motion of a track, means the direction or axis that a single track would travel along upon outfitting the track with one or more wheels, sprockets, pulleys or other rotational drive mechanisms, placing the track on a surface, and actuating those driving mechanisms. As used herein, the word lateral, when used in a context relating to a direction of motion of a track, means a direction or axis parallel to the axis of rotation of a wheel, sprocket pulley or other rotational drive mechanism when placed within the track and actuated to drive the track. As used herein, the words longitudinal and lateral, when used in the context of a robot, refer to the direction or axis along which a robot would travel without turning, and a direction or axis along a surface of travel perpendicular to that axis, respectively. As used herein, the term chamfer or variants refers to a sloping surface at an edge or corner, and does not imply any symmetry or particular angle which the sloped surface forms with any other surface.