Title of Invention

"A ROBOTIC MANIPULATOR"

Abstract The present invention provides a very compact robotic manipulator which has a capability of carrying high payload at longer distances. The manipulator is without a rotary base and turret and has an ability to take turn about vertical axis. The manipulator comprises a base plate assembly, mounting block assembly, fore arm assembly and an extension assembly. The mounting block assembly is mounted on the base plate assembly. Forearm assembly is mounted on the mounting block assembly. Extension assembly is mounted on top of the fore arm assembly. At the end of the extension assembly a pitch assembly is mounted. A wrist assembly and a gripper are attached with the pitch assembly. The wrist assembly is mountable whenever required. The gripper is mounted on top of it. Different grippers are mountable on the same assembly by removing four bolts. The wrist is designed in such a way that interchangeability of grippers in ensured. The manipulator of the present invention is simpler is construction and easier to maintain due to the use of less rotating parts and maintenance free actuators. The manipulator is made of light metal alloys such as aluminum alloy thereby reducing the weight of total structure considerably. The manipulator can be used for automated guided vehicle (AGV) and also a suicidal manipulator for working hazardous areas like Improvised Explosive Devises (IEDs) always having a danger of explosion. It can be controlled remotely as there is a communication link in between automated guided vehicle (AGV) and control station.
Full Text Field of Invention:
The present invention relates to a Robotic Manipulator and more specifically to a manipulator based on linear actuators and detachable end effectors.
Prior Art:
An industrial robot is defined as "a reprogrammable multifunctional manipulator designed to move materials, parts, tools or special devices through variable programmable motions for the performance of a variety of tasks." Robot is a generic term used for manipulators, walking machines and bipedal. There are three basic rules for design of any robot called as ground rules of robots as mentioned below:
a. A robot may not injure a human being or, through inaction, allow a
human to be harmed.
b. A robot must obey orders given by humans except when that
conflicts with the First Law.
c. A robot must protect its own existence unless that conflicts with the
First or Second Laws.
Presently, robots are used in different areas which can be categorised on the following basis:
1. Robots working in hazardous environment.
2. Robots serving for non-hazardous environment.
Robots in hazardous environment are used in different areas like nuclear waste handling, mine detection and IED handling. Robots are even serving in industries like automobile assembly lines, medical fields etc where these are used to reduce repetitive task.
Manipulator is a type of robotic device, which are used in the condition whenever some objects need to be manipulated. At the end of manipulators generally, end effectors are mounted as per requirement of the task to be performed like welding torch, wrist and parallel grippers etc. End effectors are designed as per requirement and even effectors like suction cups or magnetic end effectors are also in use.
Robotic manipulator can be classified into different categories based on joints:
(a) Cartesian co ordinate manipulator
(b) Cylindrical manipulator
(c) Polar manipulator
(d) Jointed arm manipulator
Cartesian Co ordinate manipulators are constructed for simple application like pick and place. However, these manipulators suffer from the following disadvantages.
A drawback of these manipulators is that these are too bulky to move from one place to another.
Another drawback of these manipulators is that these can give movement in X, Y and Z axis so the work volume of total system becomes a rectangular box.
Another limitation of these manipulators is that these require some rails or guide ways to manage motion in respective direction.
Another drawback of these manipulators is that these can not have long guide ways as the beams on which these guide ways are resting are simply supported beams.
Cylindrical manipulators have a rotary joint at the base due to which the work volume of manipulator becomes space in between two concentric cylinders. These manipulators are typically made up of some gearing arrangement and motors.
A drawback of these manipulators is that the torque required by the base joint increases considerably if the distance, at which the payload is to be handled, increases.
Another drawback of these manipulators is that these always suffer from some back lash in the gearing arrangement.
Another drawback of this arrangement is that due to requirement of special drives the overall cost of the system increases.
Another drawback of these manipulators is that whenever there is CG run away condition the system experiences a jerk and to withstand such condition the system has to be made bulky.
The third category of manipulators are polar manipulators which have two joints at the bottom due to which the work volume of the manipulator becomes part of a sphere.
A drawback of such manipulators is that they have to be very precisely machined as the total number of joints increases.
These manipulators also need special drives which will be having zero back lash as the back lash will be multiplied at the tip of the linkage.
Another drawback of these manipulators is that the total reduction required at the joint becomes very high as the motor RPM is high.
A robotic manipulator has been described in a US patent 4,425,818. However, this robotic manipulator suffers from the following disadvantages.
One drawback of the robotic manipulator, as described in US patent 4,425,818, is that it needs special tooling to manufacture composite parts.
One more drawback of the above mentioned manipulator is that it has a complex structure.
One more drawback of the above mentioned manipulator is that it is meant for industrial purposes with high precision of manufacturing.
Another robotic manipulator has been described in a US patent No. 4, 435,116. However, this robotic manipulator also suffers from the following disadvantages.
One drawback of robotic manipulator, as disclosed in US patent 4,435,116, is that it has a rotating base which becomes a redundant assembly when mounted on automated vehicles.
Another robotic manipulator has been disclosed in US patent 5,692,412. However, it suffers from the disadvantage that is that it is pretty complex in construction.
Objects of the Invention:
Primary object of the invention is to provide a robotic manipulator, which has a capability of carrying higher load at longer distances.
Another object of the invention is to provide a robotic manipulator, which is without a turret and having a capability to take turn about vertical axis.
Still another object of the invention is to provide a robotic manipulator, which can be used for automated guided vehicle (AGV).
Yet another object of invention is to provide a robotic manipulator, which has C channels thereby providing neat passage for all control cabals of manipulator.
Still another object of the invention is to provide a robotic manipulator, which has a structure wherein mounting of limit switches is simplified.
Yet another object of the invention is to provide a robotic manipulator which is made of Al alloy thereby reducing the weight of the manipulator considerably.
Still another object of the invention is to provide a robotic manipulator, which can act as a suicidal manipulator for working in hazardous areas like Improvised Explosive Devises (lEDs) always having a danger of explosion. Even if explosion occurs during working, the overall financial implications in case of the manipulator of the present invention will be less as compared to complex and expensive manipulators known in the prior art.
Yet another object of the invention is to provide a robotic manipulator, which is simpler in construction.
Still another object of the invention is to provide robotic manipulator, which is easier to maintain due to the use of less rotating parts and maintenance free actuators.
Yet another object of the invention is to provide a robotic manipulator, which can be controlled remotely. As there is a communication link in between automated guided vehicle (AGV) and control station. The manipulator control commands and feedback from limit switches can be communicated through same link remotely.
Still another object of the invention is to provide a robotic manipulator, which is easier to operate.
Yet another object of the invention is to provide a robotic manipulator, which is easy to fabricate. As the components to be are plates and C channels, the overall fabrication of the total assemblies become easy.
Still another object of the invention is to provide a robotic manipulator, which has the facility of interchangeability of grippers. The mechanism of the end effectors provides facility for quick changing of grippers.
Yet another object of the invention is to provide a robotic manipulator having independent pitch and roll motion so that either of them can be used as and when required.
Still another object of the invention is to provide a robotic manipulator, which is modular in construction. The different sub assemblies of the manipulator can be dismantled and assembled as and when required with fewer tools.
Yet another object of the invention is to provide a robotic manipulator, which, when in retracted condition, maintains low center of gravity (C.G.) so that whenever an AGV is negotiating a gradient the vehicle does not topple.
Still another object of the invention is to provide a robotic manipulator, which can handle objects lying on ground as well as on top of the vehicle. The manipulator is able to reach on ground in front of the vehicle as well as on top of vehicle having height less than 1.5 m.
Yet another object of the invention is to provide a robotic manipulator, which can manipulate objects of regular as well as irregular shapes as the different grippers in the manipulator ensure this maneuverability.
Still another object of the invention is to provide a robotic manipulator, which can handle objects in any orientation as the roll and pitch motion, in addition to grippers, ensures that objects with any orientation can be manipulated.
Summary of The Invention:
According to the present invention, there is provided a very compact robotic manipulator, which has a capability of carrying high payload at longer distances. The manipulator of the present invention is without a rotary base and turret and has an ability to take turn about vertical axis. The manipulator is simpler in construction and easier to maintain due to the use of less rotating parts and maintenance free actuators. It is made of Al alloy thereby reducing the weight of total structure considerably. The manipulator can be used for automated guided vehicle (AGV) and it can also as a suicidal manipulator for working in hazardous areas like Improvised Explosive Devises (lEDs) always having a danger of explosion. The manipulator can be controlled remotely as there is a communication link in between automated guided vehicle (AGV) and control station. Control cables in the manipulator are routed through C channel.
The robotic manipulator of the present invention comprises of base plate assembly, mounting block assembly, fore arm assembly & extension assembly. Mounting block assembly is mounted on the base plate assembly. Fore arm assembly is mounted on the mounting block assembly. Extension assembly is mounted on top of the fore arm assembly. At the end of the extension assembly a pitch assembly is mounted. A wrist assembly and a gripper are attached with the pitch assembly . The wrist assembly is mountable whenever required. On the top of it gripper is mounted. Different grippers are mountable on the same assembly by removing four bolts. The wrist is designed in such a way that interchangeability of grippers is ensured.
Brief Description Of Drawings:
Any further characteristics, advantages and applications of the invention will become evident from the detailed description of the preferred embodiment which has been described and illustrated with the help of following drawings wherein,
Figure 1 shows the manipulator of the present invention mounted on AGV
Figure 2 shows the isometric view of the manipulator.
Figure 3 shows the front view of the manipulator.
Figure 4 shows the extended condition of the manipulator.
Figure 5 shows the isometric view of the pitch assembly.
Figure 6 shows the front view of the pitch assembly.
Detailed Description of the Invention with Respect to Drawings:
Fig.1 shows the manipulator of the present invention mounted on an automatic guided vehicle.
Referring to Fig. 2, Fig. 3 and Fig. 4, the manipulator of present invention comprises base plate assembly (1), mounting block assembly (2), fore arm assembly (3) and extension assembly (4).
The base plate assembly (1) comprises base plate (6), stiffeners (5), front mounting block (7) and back mounting block (8). Front mounting block (7) is welded on front end of the base plate (6) while back mounting block (8) is bolted on the back end of the base plate (6). Stiffeners are the bottom "C" channels, which are welded to the base plate (6). These channels avoid bending of the base plate (6). These channels run throughout length of the base plate (6). In addition the cross section of the channels had been chosen so that it can sustain the total bending moment acting on it.
The mounting block assembly (2) comprises linear actuators (10,11), which are engaged with pins and yoke (9) to back mounting block (8) of the base plate assembly (1).
The fore arm assembly (3) comprises a forearm (13) and a linear actuator (15). Back end of the linear actuator (15) is joined with the back end of the fore arm (13) through a fore arm block (14). One end of linear actuator (15) of the fore arm assembly (3) is pivoted at one end of the fore arm (13) through a shaft (12). The same end of the fore arm (13) is pivoted at the other ends of the said liner actuators (10) & (11) of the mounting block assembly (2) through a shaft (12). It is pivoted at the other end of the said base plate (6) of the base plate assembly (1) through front mounting block (7) of the base plate assembly (1).
The extension assembly (4) comprises top mounting block (20), linear actuator (21), and a pitch assembly (22). One end of the linear actuator (21) is engaged with the top mounting block (20) and the other end of the liner actuator (21) is engaged with one end of the pitch assembly (22). One end of the linear actuator (21) of the extension assembly (4) is pivoted at front end of the linear actuator (15) of the fore arm assembly (3) through a holding bracket (16) and pin (17) provided in top mounting block (20). Further, same end of the linear actuator (21) of the extension assembly (4) is also pivoted at front end of the fore arm (13) of the fore arm assembly (3) through a holding bracket (18) and pin (19) also provided in the top mounting block (20).
Fig. 5 shows the isometric view of the pitch assembly (22) while Fig. 6 shows the front view of the pitch assembly (22). A wrist assembly (23) and a gripper (24) are attached with the pitch assembly (22). The wrist assembly is mountable whenever required. On the top of it gripper is mounted. Different grippers are mountable on the same assembly by removing four bolts.
The body of the manipulator is made of Aluminum alloy and the manipulator has capability to manipulate objects of regular as well as irregular shapes. The manipulator can be mounted on an automatic guided vehicle and it can also act as a suicidal manipulator for working in hazardous area. Further, it has independent pitch and roll motion.
The present embodiment of the invention, which has been set forth above, was for the purpose of illustration and is not intended to limit the scope of the invention. It is to be understood that various changes, adaptations and modifications can be made in the invention described above by those skilled in the art without departing from the scope of the invention, which has been defined by following claims:








We Claim:
1. A robotic manipulator for handling objects, said robotic manipulator,
comprising:
a base plate assembly (1) comprising a base plate (6), a front mounting block (7) provided near a top front end of the base plate; and a back mounting block (8) provided near a top back end of the said base plate;
a mounting block assembly (2) comprising linear actuators (10 and 11) being provided between the said front and back mounting blocks;
a forearm assembly (3) being rotatably engaged at its rear end to the front mounting block (7), wherein the said forearm assembly comprises a forearm (13), a top linear actuator (15) mounted near the rear end of the said forearm (13) with the help of a forearm block (14) and the rotational motion to the forearm assembly being provided by the said linear actuators (10 and 11), which are coupled to the forearm assembly near its rear end through a shaft (12);
an extension assembly (4) comprising a top mounting block (20), a linear actuator (21) and a pitch assembly (22) coupled to a front end of the linear actuator (21); said top mounting block having a front end comprising a holding bracket (17) and a pin (16) and a back end comprising a holding bracket (18) and a pin (19); said extension assembly (4) being rotatably engaged near a rear end of the linear actuator (21) with a front end of the forearm assembly (3) at the rear end of the said top mounting block (20) through the holding bracket (17) and pin (16) and the rotational motion to the extension assembly being provided by the top linear actuator (15), which is coupled to the extension assembly at the front end of the said top mounting block (20) through the holding bracket (18) and pin (19), the front end of the linear actuator (21) being engaged to a rear end of the said pitch assembly, and
a wrist assembly (23) and a replaceable gripper means (24) being attached to the front end of said pitch assembly for gripping an object.
2. A robotic manipulator as claimed in claim 1, wherein the wrist assembly
comprises four bolts on its front end for replacing the said gripper means.


3. A robotic manipulator as claimed in claim 1, wherein material used for the said robotic manipulator is selected from a group comprising aluminum alloy, titanium alloy or steel.
4. A robotic manipulator as claimed in claim 1, wherein said robotic manipulator is mounted on an Automatic Guided Vehicle (AGV).
5. A robotic manipulator substantially as herein described with reference to the accompanying drawings.

Documents:

1946-del-2004-Abstract-(02-06-2011).pdf

1946-del-2004-abstract.pdf

1946-del-2004-Claims-(02-06-2011).pdf

1946-del-2004-claims.pdf

1946-del-2004-Correspondence Others-(02-06-2011).pdf

1946-del-2004-correspondence-others.pdf

1946-del-2004-description (complete).pdf

1946-del-2004-Drawings-(02-06-2011).pdf

1946-del-2004-drawings.pdf

1946-del-2004-Form-1-(02-06-2011).pdf

1946-del-2004-form-1.pdf

1946-del-2004-form-18.pdf

1946-del-2004-form-2.pdf

1946-del-2004-form-3.pdf

1946-del-2004-form-5.pdf

1946-del-2004-gpa.pdf


Patent Number 249600
Indian Patent Application Number 1946/DEL/2004
PG Journal Number 44/2011
Publication Date 04-Nov-2011
Grant Date 28-Oct-2011
Date of Filing 08-Oct-2004
Name of Patentee DIRECTOR GENERAL , DEFENCE RESEARCH & DEVELOPMENT ORGANISATION (DRDO)
Applicant Address MINISTRY OF DEFENCE, GOVT OF INDIA. DTE OF ER & UOR/IPR GROUP WEST BLOCK 8, WING 1, R K PURAM NEW DELHI-110 066
Inventors:
# Inventor's Name Inventor's Address
1 ZANWAR SHANTILAL RESEARCH & DEVELOPMENT ESTABLISHMENT (ENGINEERS), DIGHI, PUNE-411 015, INDIA.
PCT International Classification Number G01C19/08
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA