RHex: A biologically inspired hexapod runner

Komsuolu, H
Saranlı, Uluç
RHex is an untethered, compliant leg hexapod robot that travels at better than one body length per second over terrain few other robots can negotiate at all. Inspired by biomechanics insights into arthropod locomotion, RHex uses a clock excited alternating tripod gait to walk and run in a highly maneuverable and robust manner. We present empirical data establishing that RHex exhibits a dynamical ("bouncing") gait-its mass center moves in a manner well approximated by trajectories from a Spring Loaded Inverted Pendulum (SLIP)-characteristic of a large and diverse group of running animals, when its central clock, body mass, and leg stiffnesses are appropriately tuned. The SLIP template can function as a useful control guide in developing more complex autonomous locomotion behaviors such as registration via visual servoing, local exploration via visual odometry, obstacle avoidance, and, eventually, global mapping and localization.


RHex: A simple and highly mobile hexapod robot
Saranlı, Uluç; KODITSCHEK, DE (2001-07-01)
In this paper, the authors describe the design and control cf, RHex, a power autonomous, untethered, compliant-legged hexapod robot. RHex has only six actuators-one motor located at each hip-achieving mechanical simplicity that promotes reliable and robust operation in real-world tasks. Empirically stable and highly maneuverable locomotion arises from a very simple clock-driven, open-loop tripod gait. The legs rotate full circle, thereby preventing the common problem of toe stubbing in the protraction (swin...
Flexible multibody dynamic modeling and simulation of rhex hexapod robot with half circular compliant legs
Oral, Gökhan; Yazıcıoğlu, Yiğit; Department of Mechanical Engineering (2008)
The focus of interest in this study is the RHex robot, which is a hexapod robot that is capable of locomotion over rugged, fractured terrain through statically and dynamically stable gaits while stability of locomotion is preserved. RHex is primarily a research platform that is based on over five years of previous research. The purpose of the study is to build a virtual prototype of RHex robot in order to simulate different behavior without manufacturing expensive prototypes. The virtual prototype is modele...
Pid and lqr control of a planar head stabilization platform
Akgül, Emre; Saranlı, Afşar; Department of Electrical and Electronics Engineering (2011)
During the uniform locomotion of legged robots with compliant legs, the body of the robot exhibits quasi-periodic oscillations that have a disturbing e ect on di erent onboard sensors. Of particular interest is the camera sensor which su ers from image degradation in the form of motion-blur as a result of this camera motion. The e ect of angular disturbances on the camera are pronounced due to the perspective projection property of the camera. The thesis focuses on the particular problem of legged robots ex...
Feature Detection Performance Based Benchmarking of Motion Deblurring Methods: Applications to Vision for Legged Robots
Gultekin, Gokhan Koray; Saranlı, Afşar (Elsevier BV, 2019-02-01)
Dexterous legged robots can move on variable terrain at high speeds. The locomotion of these legged platforms on such terrain causes severe oscillations of the robot body depending on the surface and locomotion speed. Camera sensors mounted on such platforms experience the same disturbances, hence resulting in motion blur. This is a particular corruption of the image and results in information loss further resulting in degradation or loss of important image features. Although motion blur is a significant pr...
Reactive Planning and Control of Planar Spring-Mass Running on Rough Terrain
Arslan, Omur; Saranlı, Uluç (2012-06-01)
An important motivation for work on legged robots has always been their potential for high-performance locomotion on rough terrain. Nevertheless, most existing control algorithms for such robots either make rigid assumptions about their environments or rely on kinematic planning at low speeds. Moreover, the traditional separation of planning from control often has negative impact on the robustness of the system. In this paper, we introduce a new method for dynamic, fully reactive footstep planning for a pla...
Citation Formats
R. ALTENDORFER et al., “RHex: A biologically inspired hexapod runner,” AUTONOMOUS ROBOTS, pp. 207–213, 2001, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/47702.