Harvard researchers develop vodka-powered robots for industrial use
Harvard University researchers have created tiny robots that use surface tension to do work. These futuristic bots are driven by a phenomenon called Marangoni effect, the same that allows beetles to glide across ponds and Cheerios to cluster in a bowl. The team, led by PhD student Jackson Wilt, designed these bots with 3D-printed plastic pucks, an air chamber for buoyancy, and a small alcohol fuel tank.
Marangoni effect: The driving force behind vodka-powered robots
The Marangoni effect, a flow driven by surface tension gradient, is the principle behind these robots' operation. It occurs when there's a difference in surface tension between two phases, leading to mass transfer and fluid movement. The team chose alcohol as fuel for its lower surface tension than water and because it gradually leaks out from the puck, propelling it across the water's surface without contaminating it like soap would.
Vodka and absinthe enhance robot propulsion
The researchers also noted that stronger alcohols such as vodka and absinthe offered better propulsion than weaker ones like beer. At their fastest, these robots moved at six centimeters per second and in some tests, were propelled for as long as 500 seconds. By making pucks with multiple fuel outlets and combining them, the team even built larger devices that could trace wide curves or spin in place.
Vodka-powered robots and the 'Cheerios effect'
The use of multiple pucks also enabled the researchers to investigate the "Cheerios effect," where floating objects such as cereal tend to clump together. This is especially important for small-scale on-water robots where mobility is a major challenge. The team's innovative approach could have applications in a range of industrial environments, showcasing the versatility and adaptability of these vodka-powered robots.
