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This paper presents an analysis of a novel 3-SPR parallel manipulator with 3 degrees-of-freedom that is characterized by a mobile platform consisting of a single point where all the three open-loop kinematic chains converge. The constraint singularity problem of the mechanism is solved in closed form by computing the Jacobian of the manipulator. Then, the expression of the transmission index is obtained for the 3-SPR manipulator by using the pressure angle definition. In order to evaluate the influence of secondary parameters, an equivalent 6-SPS mechanism is analyzed and its transmission index is computed in the parameter space. Finally, the proposed manipulator is compared to a standard 3-SPR parallel mechanism to investigate the influence of the mobile platform radius over transmission index and workspace volume. The results are discussed in order to highlight the advantages and disadvantages of the proposed structure of parallel manipulator.

This paper presents a novel exoskeleton mechanism for finger motion assistance. The exoskeleton is designed as a serial 2-degrees-of-freedom wearable mechanism that is able to guide human finger motion. The design process starts by analyzing the motion of healthy human fingers by video motion tracking. The experimental data are used to obtain the kinematics of a human finger. Then, a graphic/geometric synthesis procedure is implemented for achieving the dimensional synthesis of the proposed novel 2 degrees of freedom linkage mechanism for the finger exoskeleton. The proposed linkage mechanism can drive the three finger phalanxes by using two independent actuators that are both installed on the back of the hand palm. A prototype is designed based on the proposed design by using additive manufacturing. Results of numerical simulations and experimental tests are reported and discussed to prove the feasibility and the operational effectiveness of the proposed design solution that can assist a wide range of finger motions with proper adaptability to a variety of human fingers.

This paper describes the design of a gripper for horticulture product grasping. The design solution has been achieved by means of a systematic approach by evaluating all the possible architecture. The proposed structure is optimized and numerically simulated. Then, a prototype has been built and tested in laboratory. The design process and test results are discussed to show the efficiency of the built prototype with lab tests.

Efficient path planning for hyper-redundant continuum and snake-like robots is a challenging task due to limited sensing capabilities, high computational loads, multiple possible solutions, and non-linear models. This paper presents a new approach to snake robot navigation and coiling, with an algorithm that enables online step-by-step position adjustment with a follow-the-leader strategy, significantly improving the performance of the robot when compared to previous methods. The proposed algorithm is demonstrated on a 16-degree-offreedom snake-like robot for inspection and maintenance tasks in nuclear facilities.

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In this paper, the mechanical design of the LARMbot 2, a low-cost user-oriented humanoid robot was presented. LARMbot 2 is characterized by parallel architectures for both the torso and legs. The proposed design was presented with the kinematics of its main parts—legs, torso, arms—and then compared to its previous version, which was characterized by a different leg mechanism, to highlight the advantages of the latest design. A prototype was then presented, with constructive details of its subsystems and its technical specifications. To characterize the performance of the proposed robot, experimental results were presented for both the walking and weight-lifting operations.