Analysis of separate channels in a multi-connected control system

• Main Author: Natalja Ashhepkova
• Format: Article
• Language: English
• Published: PC Technology Center 2020-12-01
• Series: Technology Audit and Production Reserves
• Subjects: autonomous mobile robot of variable configuration; anthropomorphic manipulator; four degrees of mobility; separate channel.
• Online Access: http://journals.uran.ua/tarp/article/view/220979
• ISSN: 2664-9969; 2706-5448

The object of research is the control system of an autonomous mobile robot equipped with an anthropomorphic manipulator with four degrees of mobility. When a mobile robot of variable configuration moves along a given route, the control system must ensure a minimum deviation of the center of mass of the platform from a given trajectory. In this case, the control moments are directed along the axes of the coordinate system associated with the platform of the autonomous mobile robot. With relative movements of the manipulator, the tensor of inertia of the system of bodies in the coordinate system associated with the platform becomes off-diagonal and non-stationary, which determines the interconnection of control channels. The number of control actions: when moving the trajectory – four (for each wheel), when the manipulator is working – four (for each generalized coordinate). Thus, the control system is multidimensional, the connection between control channels is carried out due to the physical properties of the control object. The paper presents the results of the first stages of the development of a multi-connected control system: study of separate control channels, synthesis of a separate controller, adjustments of the controller and analysis of the quality of the created control system. The research is carried out using matrix transfer functions; Besekersky formulas are applied to determine the parameters of the desired transfer function. During the analysis, logarithmic and amplitude frequency characteristics were constructed for each separate channel, a block diagram was chosen, and a transfer function was compiled. The quality assessment of the synthesized separate channel is carried out according to the following criteria: accuracy, speed, oscillation, transient time, overshoot, amplitude and phase distortions, stability margins. The properties of the synthesized separate channel in terms of accuracy, speed and oscillation correspond to the conditions. Further research and synthesis of multi-connected control systems of a mobile robot with a manipulator will increase its survivability and efficiency in autonomous operation. Since a mobile robot with a manipulator is an example of an «autonomous mobile robot of variable configuration» object class, the results obtained can be applied to all objects of this class.