Joint kinematics

The manipulator constitutes the mechanical system of the robot and Is composed of two essential elements various parts, linked via suitable joints (kinematic pairs), which are responsible for the robot s movements (translation and rotation), and gripping devices which mimic the actions of the human... 

Woltring H.J., Huiskes R., deLange A., and Veldpaus F.E. 1985. Finite centroid and helical axis estimation from noisy landmark measurements in the study of human joint kinematics. ]. Biomech. 18 379. 

As indicated earlier, the information available for cHnical gait interpretation may include static physical examination measures, stride and temporal data, segment and joint kinematics, joint kinetics, electromyograms, and a video record. With this information, the clinical team can assess the patienf s gait deviations, attempt to identify the etiology of the abnormahties and recommend treatment alternatives. In this way, clinicians are able to isolate the biomechanical insufficiency that may produce a locomotive impairment and require a compensatory response from the patient. For example, a patient may excessively elevate a pelvis (compensatory) in order to gain additional foot clearance in swing, which is perhaps inadequate due to a weak ankle dorsiflexor (primary problem). 

Given the limitations of each method, which should be used forward or inverse dynamics That depends on the question being asked. If one s primary interest is in joint kinematics, it makes more sense to start with a measurement of position as in the invmse dynamics approach. If one is primarily interested in muscle forces, one could argue that forward dynamics has more advantages. For esti-... 

Joint Kinematics Reiative Motion between Adjacent Anatomical Coordinate Systems... 

Gao B, Zheng NN (2010) Alterations in three-dimensional Joint kinematics of anterior cruciate ligament-deficient and -reconstructed knees during walking. Clin Biomech 25 222-229... 

However, limitations of the abovementioned analysis were how accurate the joint kinematics and timing of peak GRF could be estimated from the relatively low... 

Koga H, Nakamae A, Shima Y, Iwasa J, Myklebust G, Engebretsen L, Bahr R, Krosshaug T (2010) Mechanisms for noncontact anterior cruciate ligament injuries knee Joint kinematics in 10 injury situations from female team handball and basketball. Am J Sports Med 38 (ll) 2218-2225... 

It is reported that patients ability to remrn to their preinjury activity level after anterior cruciate ligament (ACL) reconstruction is stiU low [34]. One of the possible reasons is that abnormal knee joint kinematics remain despite anterior knee laxity has been improved by the ACL reconstruction. Indeed abnormal joint... 

Della Croce, U., Leardini, A., Chiari, L., and Cappozzo, A., Human movement analysis using stereophotogrammetry—Part 4 Assessment of anatomical landmark misplacement and its effects on joint kinematics. Gait Posture, 21, pp. 226-237, 2005. 

The instrumented platform will measure the vertical ground reaction force while the wearable accelerometer subsystem will measure the relevant joint kinematics. The datalogging system consists of signal conditioning circuitry. Finally, the computer system was used to store and analyse gait parameters collected by the system. Fig. 1 shows the overview setup of the proposed system. 

There are two different sensor subsystems namely, the wireless wearable accelerometer subsystem, and instrumented platform. The function of wireless wearable accelerometer subsystem is to measure joint kinematics and instrumented platform to quantify the vertical ground reaction forces of human movement. 

Cheze L (2000) Comparison of different calculations of three-dimensional joint kinematics from video-based system data. J Biomech, 33, pp. 1695-9. 

Jindrieh D, Balakrishnan A, Deimerlein J (2004) Effects of keyswitch design and finger posture on finger joint kinematics and dynamics during taping on computer keyswitches. Clinical Biomechanics 19 600-608... 

Research on improving robot positioning accuracy due to link/joint parameter errors has concentrated mostly on the effects of these errors on the kinematic performance of the robot. This paper extends this error-related analysis to the dynamic performance of the robot, by presenting the deviations in robot manipulator torque for several cases in which link/joint kinematic parameter errors exist. The deviation in manipulator joint torque due to robot link/joint kinematic parameter errors was studied for a two-link revolute robot manipulator. Algorithms have been developed that successfully compute such joint torque deviations. A simple robot task cases was studied. The results shows the contribution of joint torque deviation due to the small kinematic parameter errors. 

One of the main research efforts devoted to robotics is to investigate the effect of the robot link/joint kinematic errors on the robot end-effector positioning accuracy [1]. In the recent years, robot manipulators are being required to perform more complicated tasks instead of simple pick and place motions. The rapid development of CAD/CAM systems, off-line robot programming, and use of sensor guided robots have also required that robot end-effectors move more accurately in Cartesian task space. This robot position accuracy study is concentrated on robot kinematic model correction and improvement, mainly because the majority of robot manipulators used in industry are controlled based on robot kinematics. 

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