Control of underactuated planar pronking through an embedded spring-mass Hopper template

Autonomous use of legged robots in unstructured, outdoor settings requires dynamically dexterous behaviors to achieve sufficient speed and agility without overly complex and fragile mechanics and actuation. Among such behaviors is the relatively under-studied pronking (aka. stotting), a dynamic gait in which all legs are used in synchrony, usually resulting in relatively slow speeds but long flight phases and large jumping heights. Instantiations of this gait for robotic systems have been mostly limited to open-loop strategies, suffering from severe pitch instability for underactuated designs due to the lack of active feedback. However, both the kinematic simplicity of this gait and its dynamic nature suggest that the Spring-Loaded Inverted Pendulum model (SLIP) would be a good basis for the implementation of a more robust feedback controller for pronking. In this paper, we describe how template-based control, a controller structure based on the embedding of a simple dynamical "template" within a more complex "anchor" system, can be used to achieve very stable pronking for a planar, underactuated hexapod robot. In this context, high-level control of the gait is regulated through speed and height commands to the SLIP template, while the embedding controller ensures the stability of the remaining degrees of freedom. We use simulation studies to show that unlike existing open-loop alternatives, the resulting control structure provides explicit gait control authority and significant robustness against sensor and actuator noise.


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Celikkanat, Hande; Şahin, Erol (Springer Science and Business Media LLC, 2010-09-01)
In this paper, we study how a self-organized mobile robot flock can be steered toward a desired direction through externally guiding some of its members. Specifically, we propose a behavior by extending a previously developed flocking behavior to steer self-organized flocks in both physical and simulated mobile robots. We quantitatively measure the performance of the proposed behavior under different parameter settings using three metrics, namely, (1) the mutual information metric, adopted from Information ...
Control of hexapedal pronking through a dynamically embedded spring loaded inverted pendulum template
Ankaralı, Mustafa Mert; Saranlı, Afşar; Department of Electrical and Electronics Engineering (2010)
Pronking is a legged locomotory gait in which all legs are used in synchrony, usually resulting in slow speeds but long flight phases and large jumping heights that may potentially be useful for mobile robots locomoting in cluttered natural environments. Instantiations of this gait for robotic systems suffer from severe pitch instability either due to underactuated leg designs, or the open-loop nature of proposed controllers. Nevertheless, both the kinematic simplicity of this gait and its dynamic nature su...
Control of Planar Spring-Mass Running Through Virtual Tuning of Radial Leg Damping
Secer, Gorkem; Saranlı, Uluç (Institute of Electrical and Electronics Engineers (IEEE), 2018-10-01)
Existing research on dynamically capable legged robots, particularly those based on spring-mass models, generally considers improving in isolation either the stability and control accuracy on the rough terrain, or the energetic efficiency in steady state. In this paper, we propose a new method to address both, based on the hierarchical embedding of a simple spring-loaded inverted pendulum (SLIP) template model with a tunable radial damping coefficient into a realistic leg structure with series-elastic actua...
Control of quadruped walking behavior through an embedding of spring loaded inverted pendulum template
Yılmaz, Mert Kaan; Saranlı, Uluç; Department of Computer Engineering (2022-8)
Legged robots require complex dynamical behaviours in order to achieve stable, sustainable and efficient locomotion. Due to their mobile nature, they can neither afford to provide extensive computational power, nor use anything but the most energy efficient structural designs and algorithms to achieve stability and speed. Consequently, simple and efficient ways to solve the complex set of problems is one of the key points of focus in legged robot locomotion research. This thesis offers a novel method that u...
Multiple human trajectory prediction and cooperative navigation modeling in crowded scenes
Hacinecipoglu, Akif; Konukseven, Erhan İlhan; Koku, Ahmet Buğra (Springer Science and Business Media LLC, 2020-07-01)
As mobile robots start operating in environments crowded with humans, human-aware navigation is required to make these robots navigate safely, efficiently and in socially compliant manner. People navigate in an interactive and cooperative fashion so that, they are able to find their path to a destination even if there is no clear route leading to it. There are significant efforts to solve this problem for mobile robots; however, they are not scalable to high human density and learning based approaches depen...
Citation Formats
M. M. Ankaralı and U. Saranlı, “Control of underactuated planar pronking through an embedded spring-mass Hopper template,” AUTONOMOUS ROBOTS, pp. 217–231, 2011, Accessed: 00, 2020. [Online]. Available: