The demand and the potential for automation in the construction sector is unmatched, particularly for increasing environmental sustainability, improving worker safety and reducing labor shortages. We have developed an autonomous walking excavator - based one of the most versatile machines found on construction sites - as one way to begin fulfilling this potential. This article describes the process of converting an off-the-shelf construction machine into an autonomous robotic system. First we outline the necessary sensing equipment for full autonomy and the novel actuation of the legs, and compare three different complementary actuation principles for the excavator's arm. Second, we solve the state estimation problem for a general wheeled-legged robot. Beside kinematic measurements, it includes GNSS-RTK, to absolutely reference the machine on a construction site. Third, we developed individual controllers for driving, chassis balancing and arm motions allowing for fully autonomous operation. Lastly, we highlight the machine's potential in four different real-world applications, e.g. autonomous trench digging, autonomous assembly of dry stone walls, autonomous forestry work and semi-autonomous teleoperation. On top, we also share some development insights and possible future research directions.

建筑行业对自动化的需求和潜力是无与伦比的，特别是在提高环境可持续性、提高工人安全和减少劳动力短缺方面。我们开发了一种自动步行挖掘机 - 基于建筑工地最通用的机器之一 - 作为开始发挥这一潜力的一种方式。本文介绍了将现成的建筑机械转换为自主机器人系统的过程。首先，我们概述了实现完全自主和新型腿部驱动所需的传感设备，并比较了挖掘机手臂的三种不同的互补驱动原理。其次，我们解决了一般轮腿机器人的状态估计问题。除了运动学测量，它还包括 GNSS-RTK、绝对参考施工现场的机器。第三，我们开发了用于驾驶、底盘平衡和手臂运动的独立控制器，允许完全自主操作。最后，我们强调了该机器在四种不同的实际应用中的潜力，例如自主挖沟、自主组装干石墙、自主林业工作和半自主远程操作。最重要的是，我们还分享了一些发展见解和未来可能的研究方向。自主林业工作和半自主远程操作。最重要的是，我们还分享了一些发展见解和未来可能的研究方向。自主林业工作和半自主远程操作。最重要的是，我们还分享了一些发展见解和未来可能的研究方向。