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Mechanical Design of a Slider-Crank Mechanism for a Knee Orthotic Device Using the Jaya Algorithm
Published in Satya Bir Singh, Prabhat Ranjan, A. K. Haghi, Applied Mechatronics and Mechanics, 2020
Ramanpreet Singh, Vimal Kumar Pathak
Single DF walking mechanism is another area in which researchers are working actively. Various synthesis techniques and mechanisms have been explored for designing them. A cam-driven mechanism in which a cam system attached to the body frame connects the feet of the robot through a pantograph mechanism that can be used [31]. A six-bar linkage can be used to approximate the femur and tibia motions while a third leg can be included to ensure the frontal stability [32]. Alternatively, a six-bar Stephenson III mechanism can be used for designing a walking linkage. The mechanism can be synthesized in two stages; four-bar linkage that generates the inverted gait should be synthesized in the first stage followed by the synthesis of a dyad that inverts and magnify the gait [33]. Another six-bar linkage, i.e., Klann linkage can also be used for producing a variety of gaits [34].
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Published in Carl W. Hall, Laws and Models, 2018
Keywords: area, crushing, grinding, particle, surface RITTINGER, Peter Ritter von, 1811-1872, German engineer Sources: Brown, G. G. et al. 1950; Hunt, D. D. 1979; NUC; Perry, J. H. 1950. See also BOND; KICK ROBERTS LAW (1875); ROBERTS-CHEBYSHEV (1878) THEOREM For every mechanical linkage, there are at least two substitutes that will produce the same desired motion, and the two alternative linkages are related to the first by a series of similar triangles. Based on the Roberts-Chebyshev theorem, there are three different but related fourbar mechanisms generating the same coupler curves. For a six-bar cognate linkage, the coupler point curve of a planar four-bar linkage is also described by the joint of the dyad of a proper six-bar linkage. Keywords: design, linkage, mechanical, mechanisms, triangles ROBERTS, S. nineteenth century, English mathematician CHEBYSHEV, Pafnuty Lvovich, 1821-1894, Russian mathematician Sources: Machine Design v. 31, n. 8, Apr. 16, 1959; Merriam-Webster Biographical. 1995; Rothbart, H. A. 1996; Shigley, J. E. 1961. ROBERTS STRAIGHT LINE SLIDER LINKAGE For a straight line slider-crank mechanism, there are two different planar mechanisms that will trace identical coupler curves. Roberts straight line mechanisms produce approximately a straight line at B when C is moved.
Research on the simulation of the PUMA 560 robot based on Matlab
Published in Fei Lei, Qiang Xu, Guangde Zhang, Machinery, Materials Science and Engineering Applications, 2017
Zhongyi Wei, Chenghao Zhu, Zhen Yang
The direct kinematic problem, the problem about direct kinematics is the geometric parameters of the robot and the displacement of the joint, the position and orientation of the terminal connecting rod coordinate system, is relative to the base coordinate system. The homogeneous transformation matrix A1 indicates the first connecting rod and it is relative to the position and attitude of the base coordinate system. A2 represents the second link relative to the first link of the position and attitude of the six-bar linkage robot. The T-matrix can be calculated as follows: T6=A1A2A3A4A5A6
Optimum design and analysis of a novel planar eight-bar linkage mechanism
Published in Mechanics Based Design of Structures and Machines, 2023
Recep Halicioglu, Assylbek Jomartov, Moldir Kuatova
In recent years, Stephenson mechanisms have begun to be considered for the press machines. Studies related to this mechanism have generally included synthesis of the mechanism dimensions. Hsieh and Tsai (2012) optimized a Stephenson-I mechanism design for the press system that would be used in a deep drawing process. A generalized Oldham coupling drove this mechanism. They got optimized linkage motion. Plechnik and McCarthy presented kinematic studies of the Stephenson-II and Stephenson-III six-bar linkages by sorting them into pairs of function generate cognates (Plecnik and McCarthy 2016a, 2016b). Hu, Sun, and Cheng (2016) proposed a Stephenson six-bar knuckle-joint linkage for mechanical servo presses consisting of a frame, crank, and slider connected by a knee mechanism. The knuckle-joint mechanism consisted of a rocker and a connecting rod connected to a crank through a three-joint link. Jomartov et al. (2020) studied the design of a Stephenson II six-bar linkage mechanism actuated by a servo motor. They also presented kinematic results. Tuleshov, Merkibayeva, and Akhmetova (2020) developed a kinematic synthesis method of Stephenson lever link mechanisms based on the mean-square minimization of the objective function. Although Stephenson mechanisms have been used for different purposes, it has been tried to focus on either the dwell motion or the slider balance by this mechanism used in press machines. While there has been no solution for both, it has been observed that the obtained dwell movements are not smooth.
RoboWalk: augmented human-robot mathematical modelling for design optimization
Published in Mathematical and Computer Modelling of Dynamical Systems, 2021
S. Ali A. Moosavian, Mahdi Nabipour, Farshid Absalan, Vahid Akbari
Offline dimensional optimization has lots of applications in multi-body systems [27, 28, 29] and robotic industries. Shim et al. have designed a robotic gripper for the front-end module assembly process and optimized a six-bar linkage by a multi-objective optimization approach [30]. Pan et al. designed a scissor mechanism for load-carrying augmentation [31]. In [32] a length optimization of the scissor sides to minimize the transmitting errors between the input and output motions in walking were performed. In another study, a passive upper limb exoskeleton was designed [33] and its elastic elements’ impedance were optimized by genetic algorithm. Authors in [34] designed pleated pneumatic artificial muscles to obtain a lightweight design by maximizing the compactness of the actuator.
Development of a High-Speed Two-Disc Tribometer for Evaluation of Traction and Scuffing of Lubricated Contacts
Published in Tribology Transactions, 2020
Michael J. Handschuh, Ahmet Kahraman, Neil E. Anderson
The radial loading of the discs was controlled by a linear hydraulic actuator ⑨, which pushed one disc against the other, whose center was stationary. Except for the motor, the entire left (driven) side of the test machine rested on a linear bearing slide ⑩. The motor was fixed underneath the testing tabletop on an intermediate level. A six-bar linkage setup was used to allow the entire setup to slide horizontally, while maintaining an appropriate belt tension. This allows the same machine to be used for testing discs of various sizes. It also allows easy access to discs in its retracted state for assembly and maintenance purposes. A ±13.3 kN load cell ⑫ was placed between the output shaft of the hydraulic actuator and the driven side bearing housing. In this configuration, the hydraulic actuator had the capacity to apply contact forces up to 10 kN.