Optimization of Central Pattern Generator-Based Torque-Stiffness-Controlled Dynamic Bipedal Walking

Abstract

In this paper, we propose a central pattern generator-based model to control the walking motion of a biped robot. The model independently controls the joint torque and joint stiffness in real time. Instead of the phase-dependent neural model used by Huang in 2014, we adopt the same structure for all the walking phases, reducing the number of connections between neurons. This reduction enables the employment of the particle swarm algorithm to find the optimal values of these parameters which lead to different solutions with different performance criteria. The simulation of the proposed method on a seven-link bipedal walking model gave a good performance in the range of walking speeds, which is referred to as versatility, and in walking pattern transition. The achieved walking gaits are 1-period cyclic motions for all the input control signals except for few gaits. Besides, these 1-period cyclic motions have a good local and global stability. Finally, we expanded our neural model by adding connections that work only when the robot walks on uneven terrains, which improved the robot’s performance against this kind of perturbation.

Multimotor Drive Control Method of Upper-Retort-Robot Based on Machine Vision

“…e target is converted into an image signal through an image pickup device and is sent to the image processing system [18]. e pixel distribution, brightness, color, and other information are converted into digital signals, and the target features are extracted to control the actions of the field equipment [19].…”

“…A chassis, a column, two mechanical arms, a servo motor that controls the rotation of the chassis and the rotation of the mechanical arm, and an Jiaolong motor that detects the mixing action are the key components of the robot [19,20].…”

Multi-motor Drive Control Method of Upper-Retort-Robot Based on Machine Vision

“…In formula (19),  represents the current axis after transformation. After the harmonic current is injected, the output torque performance of the motor is improved, but the introduced harmonic current will increase the stator copper consumption and reduce the motor efficiency.…”

“…Then start the feeding equipment to send the raw materials into the hopper, and the raw materials reach the sprinkler under the push of the screw. The spreading port automatically adjusts the spreading position according to the thickness of the material layer fed back by the vision system and the air leakage in the barrel to ensure that the raw materials are spread evenly and the thickness is consistent until the entire barrel is spread [19,20]. The working principle of the feeding system is as Figure 4.…”

“…Among the above three sets of formulas;  and  represent the axis of harmonic current; a represents a positive integer. Take the above formula as an example; delete the columns related to the 5th and 7th harmonic currents in the transformation matrix to obtain the transformation matrix as shown in matrix (19).…”