Design and control of cooperative ball juggling DELTA robots without visual guidance

Abstract

SUMMARYCooperative ball juggling is one of the most difficult tasks when performed through autonomous robots. States of the ball (position and velocity) play a vital role for the stability and duration of a long rally. Cameras are normally used in ball juggling to calculate these parameters, the use of which is not only computationally expensive but also requires a lot of hardware to determine. In this paper, we propose a control loop for cooperative ball juggling using parallel DELTA robots without visual guidance. In contrast to using a visual system for ball states feedback, an observer based on the reflection laws is designed to calculate the continuous position and velocity of the ball during juggling. Besides the conventional controller blocks, the proposed control loop consists of the ball prediction and the plate striking movement generation blocks. Two controllers are designed for the stability and tracking of variable reference height of the ball during juggling: One controller calculates the velocity of the striking plate to achieve the reference height of the ball during juggling and the second controls the actuator angles. A simulation study and hardware experiments show applicability of the designed observer and validation of the proposed control loop.

Interception of an aerial manoeuvring target using monocular vision

“…In the literature, interception of a target using visual information is achieved by generating acceleration command using position-based visual servoing (PBVS) techniques [1,2,3,4,5,6], image-based visual servoing (IBVS) techniques [7,8,9] or a control strategy based on target dynamics on the image plane [10,11,12,13]. In the case of PBVS techniques, the control command is generated based on the reconstruction of the target pose in 3D, whereas in IBVS techniques, the control command is generated based on the desired location of the target pixel involving the interaction matrix.…”

Design and Development of a Novel 2-Degree-of-Freedom Parallel Robot

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