This paper first designs a new 5-DOF parallel mechanism with 5PUS-UPU, and then analyses its DOF by traditional Grubler–Kutzbach and motion spiral theory. It theoretically shows that the mechanism meets the requirement of five dimensions of freedoms including three-dimensional movement and two-dimensional rotation. Based on this, the real mechanism is built, but unfortunately it is found unstable in some positions. Grassmann line geometry method is applied to analyze its unstable problem caused by singular posture, and then an improving method is put forward to solve it. With the improved mechanism, closed loop vector method is employed to establish the inverse position equation of the parallel mechanism, and kinematics analysis is carried out to get the mapping relationships between position, speed, and acceleration of moving and fixed platform. Monte Carlo method is used to analyze the workspace of the mechanism, to explore the influencing factors of workspace, and then to get the better workspace. Finally, an experiment is designed to verify the mechanism working performance.

The “independent extrusion” 3D printer of Continuous Fiber Reinforced Thermoplastic Composites (CFRTPC) is gradually recognized by the market, but it cannot be widely used due to the limitations of printing materials. This paper focuses on the development of Continuous Glass Fiber Reinforced Filament- Polylactic Acid (CGFRF-PLA) for “independent extrusion” printing. The preparation device of Continuous Fiber Reinforced Filament (CFRF) was designed, and the effects of preparation process parameters such as temperature, speed and coupling agent on the performance index of CGFRF-PLA were studied by experiments, the best preparation process parameters were determined.

This paper first designs a new 5-DOF parallel mechanism with 5PUS-UPU for multi-directional 3D printing, and then analyses its DOF by traditional Grubler-Kutzbach and motion spiral theory. It theoretically shows that the mechanism meets the requirement of 5 dimensions of freedoms including three-dimensional movement and two-dimensional rotation. Basing on this, the real mechanism is built, but unfortunately it is found unstable in some positions. Grassmann line geometry method is applied to analyze its unstable problem caused by singular posture, and then an improving method is put forward to solve it. With the improved mechanism, closed loop vector method is employed to establish the inverse position equation of the parallel mechanism, and kinematics analysis is carried out to get the mapping relationships between position, speed and acceleration of moving and fixed platform, Monte Carlo method is used to analyze the workspace of the mechanism, to explore the influencing factors of workspace, and then to get the better workspace. Finally an experiment is designed to verify the mechanism working performance to satisfy the spatial motion requirements of multi-directional 3D printing.

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