Electrical Contact Resistance of Fractal Rough Surfaces
The presence of roughness at electrical contacts tends to involve contacting asperities across multiple scales. Depending on the nature of the contact between asperities on opposing surfaces, different conduction mechanisms take place. This is shown in the figure here.
In essence, we are sensor-clad soft machines capable of myriad intricate tasks. Stripped from proprioceptive feedback, we can no longer walk despite intact locomotor system. Likewise, integration of sensors, complex control loops, or machine learning is crucial in “classical” robotics. This JClub entry discusses recent efforts and challenges of merging soft electronics with robotics.
dear collegues
Our recent work introduces a microscopically motivated model for the swelling response of polymer networks with non-covalent cross-linking bonds.
As opposed to the classical theories of rubber, we show that the uptake of water in polymer networks comprising hydrogen cross-linking bonds can lead to the dissociation of cross-links. This phenomenon leads to a reduction in the chain-density, an increase in entropy, and a decrease in the free energy. As a result, the network experiences significant softening and exhibits a different mechanical response.
Contact stiffness of multiscale surfaces by truncation analysis
In this concise piece of work, an effective method is shown to gain new understandings into the role of surface structure in the field of contact mechanics. In particular, normal contact stiffness is correlated to parameters of surfaces' fractal dimension and amplitude.
