|
|
|
| Stability and agility: biped running over varied and unknown terrain |
| Yang Yi, Zhi-yun Lin |
| College of Electrical Engineering, Zhejiang University, Hangzhou 310027, China |
|
|
|
Abstract We tackle the problem of a biped running over varied and unknown terrain. Running is a necessary skill for a biped moving fast, but it increases the challenge of dynamic balance, especially when a biped is running on varied terrain without terrain information (due to the difficulty and cost of obtaining the terrain information in a timely manner). To address this issue, a new dynamic indicator called the sustainable running criterion is developed. The main idea is to sustain a running motion without falling by maintaining the system states within a running-feasible set, instead of running on a periodic limit cycle gait in the traditional way. To meet the precondition of the criterion, the angular moment about the center of gravity (COG) is restrained close to zero at the end of the stance phase. Then to ensure a small state jump at touchdown on the unknown terrain, the velocity of the swing foot is restrained within a specific range at the end of the flight phase. Finally, the position and velocity of the COG are driven into the running-feasible set. A five-link biped with underactuated point foot is considered in simulations. It is able to run over upward and downward terrain with a height difference of 0.15~m, which shows the effectiveness of our control scheme.
|
|
Received: 06 August 2014
Published: 03 April 2015
|
|
|
稳定与灵活：基于欠驱动机器人在未知变化环境的奔跑运动控制
目的：针对欠驱动机器人稳定与灵活性差的难点，设计一类欠驱动控制策略实现其在未知连续坡度变换地面环境下持续奔跑运动，增强机器人对未知复杂环境的适应能力。
创新点：(1)以奔跑持续性准则代替稳定性判据，为灵活非周期奔跑运动提供理论依据。(2)以落脚速度控制代替落脚位置控制策略，提高机器人对未知变化环境适应能力。
方法：(1)基于奔跑持续性准则设计落脚点控制策略，以落脚速度为恒速碰撞地面使得机器人每个奔跑步态着地时刻均在奔跑可行集内。(2)在每个奔跑步态设计非周期运动轨迹使得支撑阶段质心运动轨迹和腾空阶段落脚点位置始终满足落在奔跑可行集内，保证机器人在变化环境持续奔跑而不摔倒。
结论：提出奔跑持续性准则和落脚点速度控制，设计非周期运动轨迹始终满足落在奔跑可行集内，使得一类点足欠驱动机器人能够稳定灵活调节奔跑步态以适应未知连续的变化环境，极大增强了机器人复杂环境适应能力。仿真结果验证所提控制策略有效性（图4-8）。
关键词：
欠驱动奔跑机器人,
动态平衡,
未知变化环境
|
Viewed |
|
|
|
Full text
|
|
|
|
|
Abstract
|
|
|
|
|
Cited |
|
|
|
|
| |
Shared |
|
|
|
|
| |
Discussed |
|
|
|
|
