This paper proposes a novel spherical robot design. The pendulum of this robot is actuated by the step motor with cable being the transmission mechanism. Compared to the existing spherical robots, this design concept can reduce the influence of the gear backlash and pendulum vibrations. Until now, few published results have presented rigorous analysis for the asymmetry of the spherical robot system. In order to solve this issue, asymmetry is considered when the dynamic model of the spherical robot is established in our paper and then the system is decoupled into two underactuated subsystems. The relationship between the two subsystems is explored by projection method. Finally, we proposed adaptive hierarchical sliding mode controller (AHSMC), which is a combination of hierarchical sliding mode (HSMC) and adaptive laws for the eccentric moment/resistance torque estimation. The simulated and experimental results were provided to verify the proposed method for balance and velocity control.

本文提出了一种新颖的球形机器人设计。该机器人的摆锤由步进电机驱动，电缆为传动机构。与现有的球形机器人相比，这种设计理念可以减少齿轮齿隙和摆锤振动的影响。到目前为止，很少有已发表的结果对球形机器人系统的不对称性进行了严格的分析。为了解决这个问题，本文在建立球形机器人动力学模型时考虑了不对称性，然后将系统解耦为两个欠驱动子系统。两个子系统之间的关系是通过投影方法来探索的。最后，我们提出了自适应分层滑模控制器（AHSMC），这是用于偏心力矩/阻力扭矩估计的分层滑动模式（HSMC）和自适应定律的组合。提供了模拟和实验结果来验证所提出的平衡和速度控制方法。