Dynamic stability of quadruped robot walking on slope with trot gait

• Published in: 高技术通讯（英文版） Vol. 22; no. 1; pp. 1 - 9
• Main Author: 雷静桃
• Format: Journal Article
• Language: English
• Published: School of Mechatronic Engineering and Automation, Shanghai University, Shanghai 200072, P.R.China 01.03.2016
• Subjects: 偏移距离; 动态稳定性; 四足机器人; 四足步行机器人; 步态; 计算机模拟; 计算步长; 边坡角; quadruped robot; trot gait; slope; zero moment point (ZMP); stability
• ISSN: 1006-6748
• DOI: 10.3772/j.issn.1006-6748.2016.01.001

The dynamic stability of a quadruped robot trotting on slope was analyzed.Compared with crawl gait, trot gait can improve walking speed of quadruped robots.When a quadruped robot trots, each leg is in the alternate state of swing phase or supporting phase, and two legs in the diagonal line are in the same phase.The feet in the supporting phase form a supporting region on the ground.When a quadruped robot walks on slope, the vertical distance from zero moment point （ ZMP） to the sup-porting diagonal line is defined as ZMP offset distance.Whether this distance is less than the maxi-mum offset distance or not, the stability of robot trotting on slope can be judged.The foot trajectory was planned with the sinusoidal function.Based on the kinematic analysis, the ZMP offset distance of quadruped robot under different slope angles, step length and step height was calculated, then the reasonable slope angle, step length and step height for quadruped robot trotting on slope to keep dy-namic stability can be determined.On the other hand, the posture angle of quadruped robot should be controlled within the desired range.Computer simulations were executed to verify the theoretical analysis.The study will provide reference for determining reasonable step parameters of the quadru-ped robot.