The video below shows a wood stove fan. These fans function with no outside input of electricity. They use the heat gradient between the bottom of the fan in contact with the stove and the top of the fan, which is designed to radiate heat. The bottom to top flow of heat goes through an array of semiconductors. Semiconductors are used in most electronic devices today ranging from smartphones to computers. Semiconductors contain elements such as germanium or compounds such as cadmium selenide combined with specific impurities that alter their physical properties.
In the case of the fan, the elements of the semiconductor sandwiched between the hot and cooler areas of the gradient produce an electric current (Seebeck Effect) that is used to drive a small motor which rotates the blades of the fan. The rotating of the blades propels heat from the stove into the room and helps further cool the top of the fan enhancing the bottom to top heat gradient.
On a recent trip to the University of Tennessee (UT) we learned that robots were delivering food on campus, so we placed an order for Chinese food from the restaurant Panda Express. The robot arrived with our food about 25 minutes after we ordered. When we opened the lid of the robot, it played the song I had chosen (Here Comes the Sun by The Beatles). After retrieving the food and closing the lid, the robot said, “Thank you, go Vols” (the UT team is the “Volunteers”) and drove away.
These self-driving food delivery robots are the creation of the company Starship Technologies. The robots use a combination of machine learning, artificial intelligence, and sensors to cross streets and avoid pedestrians and other obstacles. They can deliver the food during rain, snow, or heat. The company has placed its robots in several university campuses in the U.S. and throughout the world.
Is this the future of food delivery? And what is next? Mail, packages, drones? The future is creeping closer and closer to the present!