ANYmal - toward legged robots for harsh environments

Abstract

This paper provides a system overview about ANYmal, a quadrupedal robot developed for operation in harsh environments. The 30 kg, 0.5 m tall robotic dog was built in a modular way for simple maintenance and user-friendly handling, while focusing on high mobility and dynamic motion capability. The system is tightly sealed to reach IP67 standard and protected to survive falls. Rotating lidar sensors in the front and back are used for localization and terrain mapping and compact force sensors in the feet provide accurate measurements about the contact situations. The variable payload, such as a modular pan-tilt head with a variety of inspection sensors, can be exchanged depending on the application. Thanks to novel, compliant joint modules with integrated electronics, ANYmal is precisely torque controllable and very robust against impulsive loads during running or jumping. In a series experiments we demonstrate that ANYmal can execute various climbing maneuvers, walking gaits, as well as a dynamic trot and jump. As special feature, the joints can be fully rotated to switch between X-and O-type kinematic configurations. Detailed measurements unveil a low energy consumption of 280 W during locomotion, which results in an autonomy of more than 2 h.

The current state and future outlook of rescue robotics

“…Modularity and reconfigurability are also appealing properties for legged robot designs (Kalouche, Rollinson, & Choset, ), particularly in SAR situations, in which the morphology of the robot can be adapted to best suit the environment in a rapid deployment. Legged platforms that are capable of being easily reconfigured for different missions with modular sensor and actuation payloads (Hutter et al, ) offer appealing properties as well, by enabling operation throughout all of the phases of the disaster cycle. One major challenge with the legged locomotion modality is the need to perceive and map the environment to plan safe footholds (Fankhauser et al, ), which operation in rough terrain is dependent upon.…”

“…One major challenge with the legged locomotion modality is the need to perceive and map the environment to plan safe footholds (Fankhauser et al, ), which operation in rough terrain is dependent upon. While many quadrupedal research platforms have been developed (with hydraulic [Semini et al, ], electrical [Seok et al, ], or series‐elastic actuation [Hutter et al, ]), only ANYmal (Hutter et al, ) has been used in real‐world applications (see Figure ). Outside of the research world, Boston Dynamics has developed several quadrupedal platforms for military applications, including BigDog (Raibert, Blankespoor, Nelson, & Playter, ), but no scientific publications exist describing any of their modern systems.…”

“…Modular quadrupedal robot ANYmal being deployed in challenging disaster environments (Hutter et al, ), highlighting its ability to navigate over rough terrain and in degraded sensing conditions, and demonstrating its resistance to fire and water [Color figure can be viewed at wileyonlinelibrary.com]…”

“…This is accomplished through the development of novel human–robot interfaces, and control and perception algorithms that allow human operators to dynamically switch between full autonomy and shared control as the rescue situation demands. Throughout the project, the member labs have made fundamental contributions in perception (Fankhauser et al, ; Gawel et al, ; Scaramuzza et al, ), control (Bellicoso, Jenelten, Gehring, & Hutter, 2018b; Faessler et al, ), and human–robot interaction (Gromov et al, ; Rognon et al, ), for flying (Falanga et al, ; Mintchev & Floreano, ), legged (Hutter et al, ), and amphibious robots (Horvat et al, 2017a). A recent research focus has been on field readiness and deployments in real‐world environments, and to that end, teams of flying, walking, and amphibious robots from NCCR have performed demonstrations in increasingly challenging and realistic environments, moving from indoor mock‐up scenarios (NCCR‐Demo, ), to the European Robotics League Emergency Robots Competition (ERL, ), and a week‐long event in a military rescue training facility.…”

Rolling in the Deep – Hybrid Locomotion for Wheeled-Legged Robots Using Online Trajectory Optimization

“…The fully torque-controlled quadrupedal robot ANYmal [4] equipped with four non-steerable, torque-controlled wheels. The robot is traversing over a wooden plank (top images), on rough terrain (left middle image).…”