Sound absorbing devices and acoustic resonators decorated with fabric

A sound absorbing device comprising:

• an acoustic resonator comprising a lossy resonator with an opening and a predefined range of acoustic frequencies;
• at least one fabric layer extending across the opening, the at least one fabric layer comprising reversible actuatable liquid crystal elastomer (LCE) fibers;
• a plurality of electrical wires extending across and in contact with the at least one fabric layer;
• and
• an electrical power source in electrical contact with and configured to supply electrical current to and heat the plurality of electrical wires and thereby the reversible actuatable LCE fibers and a cooler configured to cool the reversible actuatable LCE fibers such that an average pore size of the at least one fabric layer increases with decreasing temperature and decreases with increasing temperature.

A sound absorbing device comprising:

• an acoustic resonator comprising a lossy resonator with an opening and a predefined range of acoustic frequencies;
• at least one fabric layer extending across the opening, the at least one fabric layer comprising reversible actuatable liquid crystal elastomer (LCE) fibers such that an average pore size of the at least one fabric layer increases with decreasing temperature and decreases with increasing temperature;
• a plurality of electrical wires extending across and in contact with the at least one fabric layer;
• an electrical power source in electrical contact with and configured to supply electrical current to and heat the plurality of electrical wires and thereby the reversible actuatable LCE fibers such that an average pore size of the at least one fabric layer changes and the predefined range of acoustic frequencies of the lossy resonator is adjusted as a function of temperature;
• and
• a controller configured to command the electrical power source to supply electrical current to and heat the plurality of electrical wires and thereby the reversible actuatable LCE fibers such that an average pore size of the at least one fabric layer changes and the predefined range of acoustic frequencies of the lossy resonator is adjusted as a function of temperature.