Self-Modifying Morphology Experiments with DyRET: Dynamic Robot for Embodied Testing

Abstract

If robots are to become ubiquitous, they will need to be able to adapt to complex and dynamic environments. Robots that can adapt their bodies while deployed might be flexible and robust enough to meet this challenge. Previous work on dynamic robot morphology has focused on simulation, combining simple modules, or switching between locomotion modes. Here, we present an alternative approach: a self-reconfigurable morphology that allows a single four-legged robot to actively adapt the length of its legs to different environments. We report the design of our robot, as well as the results of a study that verifies the performance impact of self-reconfiguration. This study compares three different control and morphology pairs under different levels of servo supply voltage in the lab. We also performed preliminary tests in different uncontrolled outdoor environments to see if changes to the external environment supports our findings in the lab. Our results show better performance with an adaptable body, lending evidence to the value of self-reconfiguration for quadruped robots.

Environmental Adaptation of Robot Morphology and Control Through Real-World Evolution

“…We used the Dynamic Robot for Embodied Testing (DyRET), a mammal-inspired quadruped robot (Nygaard et al, 2019b). This custom robot was developed at the University of Oslo as a platform for evolutionary experiments, in particular for simultaneous optimization of morphology and control.…”

“…This is largely thanks to ongoing improvements in the quality and availability of the prerequisite robotic components, and the rapid adoption of flexible fabrication techniques, e.g., 3D printing, into the robot design process. There are broadly two approaches to achieve morphological robot adaptation: (i) optimize 3D-printable components and attach them to a robotic base to provide bespoke terrain-specific performance properties (Collins et al, 2018); or (ii) create a single robot with built-in adaptation abilities (Nygaard et al, 2019b). We focus on the latter approach as it allows morphology to be changed in-situ, e.g., as a real-time response to environmental stimuli.…”

Experiences from Real-World Evolution with DyRET: Dynamic Robot for Embodied Testing

“…Our robot, DyRET (Dynamic Robot for Embodied Testing), was developed to be a platform for experiments on selfadaptive morphologies and embodied cognition [6], shown in Fig. 1.…”

Evolving Modular Robots: Challenges and Opportunities

“…They also need to be tested in a physical setup to validate the solution and avoid the reality gap. In order to build the evolved robots, different approaches have been developed: 3D printing (Hale et al, 2019;Pollack and Lipson, 2000;Samuelsen and Glette, 2015), robots that can self-adjust the length of their limbs (Nygaard et al, 2019), soft robots (Hiller and Lipson, 2011) and modular robots (Stoy et al, 2010;Auerbach et al, 2014;Faiña et al, 2015;Moreno et al, 2017). However, it exists a trade-off between the morphological space that is available for evolution and the deployment time to build a robot, which is linked to the reusability of the robotic components (Moreno and Faina, 2020a).…”