Narrow Results

This paper presents the design and the experimental validation of a Series rotary Elastic Actuator (SEA). The actuator is conceived to be installed on both the knee and the ankle joint of the version three of the humanoid robot iCub. The actuator is composed of an electric motor, a gearbox, and a customized torsion spring. The stiffness value of the torsion spring is the outcome of an optimisation problem that considers several criteria, e.g., the maximum readable torque from the SEA and the total stiffness of the mechanism. Then, the synthesis of the elastic element exploits a Finite Element Method (FEM), which allows us to meet the requirements. Experiments on the conceived design have been performed on a custom set-up, and they verify the match between the desired and real value of the mechanism stiffness with a maximum resultant error of 9%. An estimation of the damping associated with the SEA is also performed during experimental validation.

Environmental impact assessment (EIA) was initially introduced as an advocacy instrument for the biophysical environment in project decision-making. Strategic environmental assessment (SEA) evolved with a similar mission for strategic level proposals. However, recent trends towards more integration, particularly in the context of sustainability assessment (SA) mean that social and economic aspects are now frequently considered on a par with the environment in impact assessment processes. There are indications that this development will ultimately favour trade-offs towards socio-economic benefits, causing adverse environmental impacts. In this paper, we discuss problems connected with these types of integrated assessments. Based on observations of SA processes are actually environmentally unsustainable, we argue that the need for environment focussed EIA and true SEA in planning processes is now greater than ever. We suggest that until power relationships develop in a way that will allow integration in an environmentally sustainable manner, practitioners should not give up the benefits that have arisen from 35 years of EIA practice. We conclude that in our current world, there is nothing wrong with environmental advocacy — let's continue to use EIA and SEA effectively to protect the environment!

This paper introduces StarlETH, a compliant quadrupedal robot that is designed to study fast, efficient, and versatile locomotion. The platform is fully actuated with high compliant series elastic actuation, making the system torque controllable and at the same time well suited for highly dynamic maneuvers. We additionally emphasize key elements of a powerful real time control and simulation environment. The work is concluded with a number of experiments that demonstrate the performance of the presented hardware and controllers.

This paper investigates the mechanical benefits of employing a passive foot segment to improve energetic efficiency in legged running. The proposed lightweight design significantly reduces impact and damping losses, while simultaneously allowing for a natural-looking stance configuration. Actuator input and ankle spring properties were optimized in simulation and successfully tested in 2D running experiments.