A Novel Review on Quadruped Robots Design Variants, Gait Modulation, and Motion Planning Schemes

Abstract

Quadruped robots are gaining more importance among researchers due to their adaptability to complex terrains, though their stability handling is complex. Quadruped robots are one of the best kinds of legged robotic systems with regard to their framework and movement flexibility. For making quadrupeds fully autonomous, it is important to concentrate on their modeling, modulation, and maneuverability. This article sheds light on quadruped robots, starting from the early-stage developments of TITAN series quadrupeds to current progress based on variations of design, gait analysis, control, and motion planning, so as to provide directions for future researchers to develop efficient quadrupeds. Furthermore, we have made a comparative analysis on various aspects, including various mobile robots, material specifications, leg structure and topology, crucial modeling parameters, sensors and actuation systems, as well as traditional and advanced algorithms. This work explores gait analysis, followed by numerous researchers concentrating on various gait stability challenges; in addition, it presents the studies on control strategies of quadruped robots based on a PID controller, neural network controller, fuzzy logic controller, delayed feedback controller, hybrid controller, and other peculiar controllers. Furthermore, the representative explorations on motion planning algorithms of quadruped robots have been done. To conclude, this paper provides an overview of the various variants of quadrupeds, focusing on important aspects, followed by an analysis of pivot features and providing solutions to current challenges and issues so as to help future researchers in the field identify key areas of research.