{"doi":"10.1089/rorep.2023.0017","title":"A Novel Variable Impedance Actuator Utilizing Adjustable Viscoelastic Properties of Thermoresponsive <i>Polycaprolactone</i>","abstract":"This article presents a design for a variable impedance actuator capable of changing stiffness and damping through the heating of a thermoplastic polymer, in an off-line manner. Typically, other actuators have additional mechanisms to regulate overall impedance, but the key component of this design uses polycaprolactone. This polymer exhibits temperature-dependent viscoelastic properties, so that at room temperature, it is rigid, and softens as temperature increases. Flexible heaters are embedded into the design for adjusting the output impedance. The variable impedance module has fixed elastic components in parallel with the variable elastic and damping components of the polymer. To show the effect of variable impedance, the motor was set to follow sinusoidal trajectories while the position of the output link was measured. As an indicator for change in the output impedance, the actuator exhibits a fivefold increase in overshoot due to a 40°C temperature increase. Although adjusting the output impedance of this device is not suitable for on-line implementation, the design is scalable and can be made compact through miniaturization of components.","journal":"Robotics Reports","year":2023,"id":385684,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":2,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9526,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2023-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1153682,"name":"Daniel Johnson","orcid":"0009-0001-8449-9771","position":1,"is_corresponding":false},{"id":1153683,"name":"Amir Jafari","orcid":"0000-0003-0593-3507","position":2,"is_corresponding":false},{"id":1153681,"name":"Trevor Exley","orcid":"0000-0003-3175-0587","position":0,"is_corresponding":true}],"reference_count":46,"raw_metadata":null,"created_at":"2026-07-19T01:17:52.636565Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}