Recovering energy from door opening and closing process using a parallel crank-slider harvester in buildings

Recovering kinetic energy from the environment is mostly focused on the natural environment, while there is also a huge energy in the human living environment. The swing door is an indispensable equipment in the human living environment. The bidirectional swing of the door opening and closing process is rich in energy generated by human motion and thus has a large potential for energy recovery. An energy harvester for recovering bidirectional kinetic energy of the door in buildings is proposed, fabricated, analyzed, and tested. The energy harvester consists of a parallel crank-slider mechanism, a transmission mechanism and a power generation module. The external linkage is used to connect the door and the energy harvester to transmit the bidirectional swing of the door. The parallel crank-slider mechanism is coupled with two one-way bearings. This can realize the conversion of the bidirectional swing of the door to the unidirectional rotation of the central shaft. The final mechanical rectification effect is achieved. Kinematic and dynamic analyses are performed to determine the factors affecting the power generation performance. A prototype is fabricated, and experiments are conducted on it by simulating the process of opening and closing the door. The experimental results are consistent with the simulation ones. At a normal opening velocity of 90° s⁻¹, the maximum open-circuit voltage of the harvester is 7.06 V and the average output power is 1.03 W. The highest efficiency of the harvester can reach 69.65%. The recovered energy is capable of powering the smart door lock for at least 150 s, as well as powering devices such as door lights and doorbells. This can meet the power supply needs of most electronic devices on doors in human life.