To approach the level of advanced human players in table tennis with robots, generating varied ball trajectories in a reproducible and controlled manner is essential. Current ball launchers used in robot table tennis either do not provide an interface for automatic control or are limited in their capabilities to adapt speed, direction, and spin of the ball. For these reasons, we present AIMY, a three-wheeled open-hardware and open-source table tennis ball launcher, which can generate ball speeds and spins of up to 15.4 ms-1 and 192 s-1, respectively, which are comparable to advanced human players. The wheel speeds, launch orientation and time can be fully controlled via an open Ethernet or Wi-Fi interface. We provide a detailed overview of the core design features, as well as open source the software to encourage distribution and duplication within and beyond the robot table tennis research community. We also extensively evaluate the ball launcher's accuracy for different system settings and learn to launch a ball to desired locations. With this ball launcher, we enable long-duration training of robot table tennis approaches where the complexity of the ball trajectory can be automatically adjusted, enabling large-scale real-world online reinforcement learning for table tennis robots.

翻译：为让机器人乒乓球达到高级人类选手的水平，以可重复且可控的方式生成多样化的球轨迹至关重要。当前用于机器人乒乓球的发球机要么未提供自动控制接口，要么在调节球速、方向及旋转方面能力有限。为此，我们提出AIMY——一款三轮驱动的开源硬件与软件乒乓球发球机，其球速与旋转速率分别可达15.4 m/s和192 rad/s，与高级人类选手水平相当。通过开放的以太网或Wi-Fi接口，可完全控制轮速、发射角度与发射时间。我们详细阐述了核心设计特征，并开源了相关软件，以促进机器人乒乓球研究领域内外的分发与复制。我们还针对不同系统设置对发球机的精度进行了全面评估，并学习了将球发射至指定位置的方法。借助该发球机，我们能够实现机器人乒乓球的长时间训练，其中球轨迹的复杂度可自动调节，从而支持大规模真实环境下的乒乓球机器人在线强化学习。