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This paper presents a comparative study on the dexterity and manipulability of three planar 1-RRR, 2-RRR and 3-RRR manipulators.After derivation of the Jacobian matrix of three manipulators, they are transformed to a homogeneous form to include components with homogenous physical units. The condition number of each Jacobian matrix is calculated. Since the condition number changes in general between 1 to ∞, its inverse is used for definition of the local condition index.A zero value for this index indicates that the Jacobian matrix is singular and consequently, the robot has the worse manipulability. On the other hand, the robot indicates the best manipulability and dexterity when this index is close to one. Furthermore, the effect of changing the platform angle on the local condition index is investigated. The manipulability of three manipulators is then compared to each other for the platform angle for which the maximum local condition index is resulted. The results show that the 3-RRR manipulator has a better dexterity than other manipulators at the platform angles less than 90 degree.For the angles greater than 90 degree, the 1-RRR manipulator has a greater local condition index which indicates more dexterity. Finally, the maximum local condition index is compared for each robot at its own workspace and common workspace of three robots.The results verify that this index has almost identical values for the already mentioned workspaces for each robot.Based on the manipulability distribution, the global condition index of theses robots are checked.The results confirm the superiority of the 3-RRR robot.

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Leisure is an opportunity for self-development, self-definition and community rejuvenation, acquisition of experience and development of social interactions. However, it is "relatively" free and constrained by factors such as gender, cultural and social policies governing societies. The current study is aimed at examining married women's leisure problems in Tehran from the viewpoint of experts. The research method is qualitative while the Thematic Analysis is used for data analysis and the illustrated problems. 23 semi-structured interviews conducted with three groups of experts (policymakers, executives and university professors). Two global themes of "Intra-governmental" and "Extra-governmental" problems are taken through the experts on the leisure problems of the target group. "Marginalization", "inequality and discrimination", "scattered policy making and implementation", "demonstrative policies" and "apathy" are "Intra-governmental problems" whereas "restriction", "excess and negligence in leisure activities" and "body as project" are forming "Extra-governmental problems". The results of this study illustrate that leisure problems for married women in Tehran have a cultural root and are caused by "cultural neglect and misunderstanding". Thus, cultural solutions can provide a framework for other solutions to function.