Robots often have to perform manipulation tasks in close proximity to people. As such, it is desirable to use a robot arm that has limited joint torques so as to not injure the nearby person. Unfortunately, these limited torques then limit the payload capability of the arm. By using contact with the environment, robots can expand their reachable workspace that, otherwise, would be inaccessible due to exceeding actuator torque limits. We adapt our recently developed INSAT algorithm \cite{insat} to tackle the problem of torque-limited whole arm manipulation planning through contact. INSAT requires no prior over contact mode sequence and no initial template or seed for trajectory optimization. INSAT achieves this by interleaving graph search to explore the manipulator joint configuration space with incremental trajectory optimizations seeded by neighborhood solutions to find a dynamically feasible trajectory through contact. We demonstrate our results on a variety of manipulators and scenarios in simulation. We also experimentally show our planner exploiting robot-environment contact for the pick and place of a payload using a Kinova Gen3 robot. In comparison to the same trajectory running in free space, we experimentally show that the utilization of bracing contacts reduces the overall torque required to execute the trajectory.
翻译:机器人往往不得不在接近人的地方执行操作任务。 因此, 最好使用一个机器人臂, 限制联合火力, 以免伤害附近的人。 不幸的是, 这些有限的石墨会限制手臂的有效载荷能力 。 通过与环境接触, 机器人可以扩大其可扩展的工作空间, 否则, 将无法进入的工作空间, 因为超过触动器触动器的极限 。 我们调整了我们最近开发的INSAT 算法\ cite{insat}, 以解决通过接触进行全臂操纵规划的扭伤问题 。 INSAT不需要事先超过接触方式序列, 也不需要初始模板或种子来优化轨迹。 INSAT通过透过图搜索来探索操纵或联合配置空间, 并使用周边解决方案进行递增轨迹优化, 以便找到动态可行的轨迹。 我们展示了各种操纵器和模拟情景的结果 。 我们还实验性地展示了我们的规划者利用机器人- 利用机器人- 环境接触来提取和放置一个使用 Kinova Gen3 机器人的有效载荷。 与在自由空间运行的轨迹上相同的轨迹, 我们实验性地展示了所需的轨迹。