DESIGN & MANUFACTURING OF ROBOT BY USING KLANN S MECHANISM

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1 DESIGN & MANUFACTURING OF ROBOT BY USING KLANN S MECHANISM Prof. S. S. Shevale 1 Shashank Kulkarni 2, Atharva Kulkarni 3, Manoj Bagal 4, Rushikesh Bhosale 5 1 Asst. Prof. Department of Mechanical Engineering, 2,3,4,5 Student Department of Mechanical Engineering, Zeal College of Engineering & research, Narhe, Pune: , India. Abstract As the wheels are ineffective on rough and rocky areas, therefore robot with legs provided with Klann s mechanism is beneficial for advanced walking vehicles. It can step over curbs, climb stairs or travel areas that are currently not accessible with wheels. The most important benefit of this mechanism is that, it does not require microprocessor control or large amount of actuator mechanisms. In this mechanism links are connected by pivot joints and convert the rotating motion of the crank into the movement of foot similar to that of animal walking. The proportions of each of the links in the mechanism are defined to optimize the linearity of the foot for one-half of the rotation of the crank. The remaining rotation of the crank allows the foot to be raised to a predetermined height before returning to the starting position and repeating the cycle. Two of these linkages coupled together at the crank and one-half cycle out of phase with each other will allow the frame of a vehicle to travel parallel to the ground. This project is useful in hazardous material handling, clearing minefields, or secures an area without putting anyone at risk. The military, law enforcement, Explosive Ordinance Disposal units, and private security firms could also benefit from applications of mechanical spider. It would perform very well as a platform with the ability to handle stairs and other obstacles to wheeled or tracked vehicles. The goal for this project is to create an eight-legged robot to test new walking algorithm. We loosely based our design on spider because there has an advanced way in robotics on octopedal locomotion. Hopefully algorithm develops will be of use to robotics community and in future society. Keywords klann s mechanism; pivot joints; microprocessor control; actuator mechanisms; A. Background I. INTRODUCTION Since time unknown, man s fascination towards super-fast mobility has been un-questionable. His never ending quest towards lightning fast travel has gained pace over the past few decades. Now, with every passing day, man is capable of covering longer distances in relatively shorter of time. Today s duration automobiles are beasts on wheels which are designed for speed and Comfort. However, most of today s automobiles are limited to roads or plain terrains. Even the off-road vehicles are of no use when the land is too rough. Needless to say, no vehicle can climb mountains. This is because all automobiles depend on rubber wheels which fare better only on roads. Man, who itself depends, on legs can travel on rocky terrains and climb mountains, but such journeys are never comfortable. Thus naturally the solution can be seen as an automobile which rests on and moves with legs. 1

2 B. Why Klann s Mechanism? The main advantage of Klann s mechanism robots is their ability to access places impossible for wheeled robots. By copying to the physical structure of legged animals, it may be possible to improve the performance of mobile robots. To provide more stable and faster walking, scientists and engineers can implement the relevant biological concepts in their design. The most forceful motivation for studying Klann s mechanism robots is To give access to places which are dirty. To give access to places those are dangerous. Job which are highly difficult legged robots can be used for rescue work after earthquakes and in hazardous places such as the inside of a nuclear reactor, giving biologically inspired autonomous legged robots great potential. Low power consumption and weight are further advantages of walking robots, so it is important to use the minimum number of actuators. In this context, an objective is set in this project to develop an eight- legged mobile robot whose structure is based on the biomechanics of insects. II. PROBLEM STATEMENT As the human being are replaced by robot in most of area. The robots are more accuracy than man. But for movement of the robot is done by the wheels. Those wheels are ineffective on the rough & rocky area. Therefore robot with legs provided with Klann s mechanism is beneficial for advanced walking vehicles. And all robots are work by the controller & hardware which required expertise. Klann s mechanism does not require microprocessor control or large amount of actuator mechanisms. III. LITERATURE SURVEY A. History of Legged Mechanism The scientific study of legged locomotion began just very a century ago when Leland Stanford, then governor of California, commissioned Edward Muyridge to find out whether or not a trotting horse left the ground with all four feet at the same time. Stanford had wagered that it never did. After Muybridge proved him wrong with a set of stop motion photographs that appeared in Scientific American in 1878, Muybridge went on to document the walking and running behavior of over 40 mammals, including humans. His photographic data are still of considerable value and survive as a landmark in locomotion research. The study of machines that walk also had its origin in Muybridge s time. An early walking model appeared in about. It used a linkage to move the body along a straight horizontal path while the feet moved up and down to exchange support during stepping. The linkage was originally designed by the famous Russian mathematician Chebyshev some years earlier. During the 80 or 90 years that followed, workers viewed the task of building walking machines as the task of designing linkages that would generate suitable stepping motions when driven by a source of power.much of the research of fatigue crack propagation rates has been concerned with the early and middle stages of crack initiation and propagation, a small portion of which has been reported in compendiums edited by Beevers [1980], Amzallag [1994], Ruschau and Donald [1995], and Marsh, Smith and Ritchie [1991]. Investigation reported in the literature has been concerned with life prediction under constant amplitude and constant y requency sinusoidal fatigue loading. An attempt to address more variation in loading, as reported by Khan, Rauf, and Younas B. Existing Design of the Leg Mechanism For legged robots, 2 DOF is the minimum required to move a leg forward by lifting and swinging. Figure shows the leg mechanism, using a Watt-chain six-bar mechanism to imitate the cockroach (insect) leg. We chose a six bar mechanism because of its superior force-transmission angle and bigger oscillating angle in comparison with other types such as the four - bar mechanism (Norton, 2004). Force transmission is very important for leg mechanisms, because of the point contact with the ground. The leg mechanism itself has one DOF for lifting, whilst the base of mechanism has another DOF for swinging. The leg mechanism, with its body size shown in Figure 1, is modeled with Solid Works. It has six links and seven cylindrical joints. The body size and link dimensions are determined from the maximum swing and lift angles. Each link is created by entering its shape and reference coordinates. To mate the contact surfaces of the parts, the assembly bar of the assembly mating menu is used. Material properties of all materials considered according to design consideration. From design considerations, the analysis carried out by using ANSYS.following methodology are used for result. C. A Mechanical Design of a Quadruped Robot It is a quadruped, electrically actuated, walking and wall climbing robot. The trunk consists of one part only, and the legs are mounted, symmetrically, on the corners of the trunk. Each leg has three links and three actuated joints connecting these links. Hip horizontal joint is used to swing the three links of the leg in a plane parallel to the ground while walking, hip vertical joint, to attach-detach the foot on and from the terrain for swing and support stages, respectively. IV. OBJECTIVES to demonstrate the working of Klann s Mechanism through a simple walking robot. To design & develop the Klann s Mechanism in CAD To fabricate of Klann s Mechanism. By using Klann Mechanism the vehicle can able to move in one plane along different direction. V. KLANN S MECHANISM The Klann linkage is a planar mechanism designed to simulate the gait of legged animal and function as a wheel replacement. The linkage consists of the frame, a crank, two 2

3 grounded rockers, and two couplers all connected by pivot joints. The proportions of each of the links in the mechanism are defined to optimize the linearity of the foot for one-half of the rotation of the crank. The remaining rotation of the crank allows the foot to be raised to a predetermined height before returning to the starting position and repeating the cycle. Two of these linkages coupled together at the crank and one-half cycle out of phase with each other will allow the frame of a vehicle to travel parallel to the ground. The Klann linkage provides many of the benefits of more advanced walking vehicles without some of their limitations. It can step over curbs, climb stairs, or travel into an area that are currently not accessible with wheels but does not require microprocessor control or multitudesof actuator mechanisms. It fits into the technological space between these walking devices and axle-driven wheels. =54 mm Diameteral Pitch, DP = Z1/d1 =36/65 =0.553 mm-1. Outside Diameter, Do = (Z1+2)/DP =(36+2)/0.55 =69.09 mm. Addendum, Dedendum, a = 1/DP =1/0.55 =1.81 mm. d = 1.157/DP =1.157/0.92 =1.9 mm. Working depth Tooth thickness W=2.25m =2.25*1.08 =2.43mm t =1.5708m =1.5708*1.08 =1.696mm Minimum bottom clearance=0.25m =0.25*1.08 =0.27mm A. Calculation of DOF Fig.1. Klann s leg mechanism VI. DESIGN AND CALCULATION In general, number of degrees of freedom of a mechanism is given by, n = 3 (l 1) 2 j Where, n Degree of freedom l Number of links j Number of joints This equation is called Kutzbach criterion for the movability of a mechanism having plane motion In Klann Mechanism, for a single leg, We have l=6; J=7 Hence Degree of freedom n = 3(6 1) 2x7 n = n = 1 B. Calculation of Dimensions of Gears Pitch Diameter, d1 = m.z1 =1.5*36 VII. DESIGN OF PARTS AND ASSEMBLY The part drawings of the model are drawn using the modeling software. And then the parts are assembled using any modeling software and thus the designing of the model is accomplished. Fig 2 CAD modeling of Klann s mechanism 3

4 A. Frames and Base Plate B. Electric Motors C. Gears D. Shafts E. Legs F. Linkages G. Klann Linkage H. Control System I. Batteries VIII. COMPONENTS IX. CONSTRUCTION AND WORKING A. Construction It consist of motor or engine mounted at the top, Out of three spur gear one is connected to motor or engine shaft called Driving gear and remaining two are meshes with driving gear. The crank is connected to the shaft on which two driven gears are mounted by the shaft. As the motor made to ON the driving gear drives, Another two gear, one is clockwise while other is anticlockwise as the gears are rotate in opposite direction. Due to this rotation resulting in the crank rotation, Crank moves the forcing link gives the momentum in a particular line of action with help of supporting link. The work of supporting link is to move the arm in a particular profile which made by the end point of arm and move back to its normal position i.e. initial position. All these give the walking motion to the arm like a spider. B. Working principle The basic working principle of Klann Mechanism is that when the crank is rotated, a series of result in a gait-like movement of the leg. If all the legs in a device are connected to a single motor, the device will be able to move in only one direction (or two directions, if the motor can rotate in both directions), this issue is resolved by using more than one motor. The device can be made to take a turn by using the motors strategically. Fig 3 fabricated mechanism The operation of the mechanism can be by temporarily installing a wired control box. The box consists of two DPDT switches wired to control the forward and backward motion of the two legs. The legs on each side should be positioned so that either the center leg touches the ground or the front and back leg touch the ground. The leg is the same as an insect s and provides a great deal of stability. To reverse, one set of legs stops (or reverses) while the other set continues. During this time, arrangement of the legs will be lost, but the robot will still be supported by at least three legs. An easy way to align the legs is to loosen the chain sprockets (so you can move the legs independently) and position the middle leg all the way forward and the front and back legs all the way back. X. ADVANTAGES OF KLANN S MECHANISM A. Advantages Klann s Mechanism makes legged mobility easier. It directly converts a rotation into a gait. Easy to build. Initial cost is reasonably low. Construction expense is low. Heavy load can be carried. It can be run in rough surfaces. Easy to control. Maintenance is less. B. Applications of Klann Mechanism It would be difficult to compete with the efficiency of a wheel on smooth hard surfaces but as condition increases rolling friction, this linkage becomes more viable and wheels of similar size cannot handle obstacles that this linkage is capable of. Toys could be developed that would fit in the palm of your hand and just large enough to carry a battery and a small motor. Eight leg mechanical spiders can be applicable for the making of robots. It has a wide range of application in the manufacturing of robots. A large version could use existing surveillance technology to convert your television into a real-time look at the world within transmitting range. It would also relay commands from the remote to the spider bike additional frequenc ies could be used to operate manipulators for retrieving the mail during unfavorable weather or taking the dog out. It can also be used for military purpose. By placing bomb detectors in the machines we can easily detect the bomb without harmful to humans. It can be used as heavy tanker machines for carrying bombs as well as carrying other military goods. It is also applicable in the goods industries for the small transportation of goods inside the industry. The mountain roads or other difficulties where ordinary vehicles cannot 4

5 be moved easily can be replaced by our six leg mechanical spider. XI. CONCLUSION This project can step over curbs, climb stairs, or travel into an area that are currently not accessible with wheels but does not require microprocessor control or multitudes of actuator mechanisms. It would be difficult to compete with the efficiency of a wheel on smooth hard surfaces but as conditions increase rolling friction, this linkage becomes more viable and wheels of similar size cannot handle obstacles that this linkage is capable of pivoting suspension arms could be used to optimize, The height of the legs for the waterline, Increase the platform height, Reduce the vehicle width. Also it allows the legs to fold up compactly for storage and delivery. Thus, all the principles and mechanisms involved in a walking robot using are studied and the practical difficulties in fabrication of a working model are understood. REFERENCES [1] J. C. Klann, Patent No , USA. [2] Design and prototype of a six-legged walking insect robot Servet Soyguder and Hasan Alli Mechanical Engineering Department, Firat University, Elazig, Turkey. [3] Mechanical Design of A Quadruped Robot for Horizontal Ground to Vertical Wall Movement Abd Alsalam Sh. I. Alsalameh Shamsudin H.M. Amin Rosbi Mamat Center for Artificial Intelligence and Robotics (CAIRO) Faculty of Electrical Enginee r ing University Teknologi Malaysia. [4] A study of availability and extensibility of Theo Jansen mechanism toward climb ing over bumps Kazuma Komoda (PY), and Hiroaki Wagatsuma 1 Department of Brain Science and Engineering, Kyushu Institute of Technology RIKEN Brain Science Institute. [5] Gabriel Martin Nelson, Learning about Control of Legged Locomotion using a Hexapod Robot with Compliant Pneumatic actuators, Case Western Research University. [6] Saranli, U. Buehler, M. and Koditschek, Rhex a simple and highly mobile hexapod robot. [7] Delcomyn, F. and Nelson, M.E., Architectures for a biomimetic hexapod robot, Robotics and Autonomous Systems. [8] Inoue H, Noritsugu T, Development of Walking Assist Machine Using Linkage Mechanism. An International Journal of Robotics and Mechatronics. 5