—This paper presents a molecular mechanics study using a molecular dynamics software (NAMD) for characterization of molecular elastic joints for bio nanorobotic prototyping. Simple protein-like elastic joints elements for structural links have been carefully studied and simulated to understand the functional limits of each one of them: fibronectin, titin, deca-alanine, fibrillin, Rop and double-helical DNA molecules. We simulated the restoring forces involved under various external mechanical stress to predict the type of force spectra, reversibility, degrees of freedom and irreversible work that may be expected from single-molecule protein manipulation experiments. Their use as elementary molecular components for bio-nanorobotic structures are also simulated and the results discussed.