This study investigates the motion of micro-parts of different sizes on a symmetrically vibratory feeder system that consists of a saw-tooth surface made of carbide, brass, and zirconia. The velocity and position of micro-parts are time-dependently measured by the particle tracking velocimetry method. We investigate the micro-parts motion for a range of frequencies applied to the surface. The obtained results show that unidirectional motion can be attained by the present feeder system regardless of the surface material and the micro-part size. The motion behavior of micro-parts varies for different experiments and surfaces in spite of the same driving voltage and frequency. This implies that the motion of micro-parts is affected by uncertainties in the system. The micro-part motion consists of numerous frequencies, and the first frequency coincided with the exciting frequency. The results also show that the carbide saw-tooth surface produces the largest micro-part velocity among the three surface materials. Comparing relationship between feeding velocity and velocity spectrum clarifies that the micro-part moves faster when spectrum was clear. The experiments on the carbide surface indicate that the micro-part moves smoothly and a large velocity is observed within 50-70 Hz of driven frequency.

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This paper develops a multi-robotic arm system and a stereo vision system to sort objects in the right position according to size and shape attributes. The robotic arm system consists of one master and three slave robots associated with three conveyor belts. Each robotic arm is controlled by a robot controller based on a microcontroller. A master controller is used for the vision system and communicating with slave robotic arms using the Modbus RTU protocol through an RS485 serial interface. The stereo vision system is built to determine the 3D coordinates of the object. Instead of rebuilding the entire disparity map, which is computationally expensive, the centroids of the objects in the two images are calculated to determine the depth value. After that, we can calculate the 3D coordinates of the object by using the formula of the pinhole camera model. Objects are picked up and placed on a conveyor branch according to their shape. The conveyor transports the object to the location of the slave robot. Based on the size attribute that the slave robot receives from the master, the object is picked and placed in the right position. Experiment results reveal the effectiveness of the system. The system can be used in industrial processes to reduce the required time and improve the performance of the production line.

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In this paper, we study experimentally the effect of the geometry parameters of a saw‐tooth surface and a micropart on the motion of the micropart. The experiments are performed for a range of the saw‐tooth pitch p, micropart length l, and exciting frequency f applied to the surface. By the use of particle tracking velocimetry method, we obtain the time‐dependent velocity and then the ensemble‐averaged velocity of the microparts. The results show that the velocity of the micropart increases up to a certain value of pf and then decreases with increasing pf. The widths of the profiles are similar for the same value of the relative scale l/p but the peaks of the profiles are slightly larger and the profiles are shifted leftward for larger pitches of the saw‐tooth surface. It implies that the motion of the micropart depends more on the characteristic surface velocity pf than on the relative scale l/p and that a larger pitch of the sawtooth creates a larger asymmetric force on the micropart. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.