Scientists from Duke University have engineered a completely electronics-free soft robot that can fly across bodies of water to perform long-range environmental monitoring such as detecting oil spills and assessing the level of acidity in water.
Dubbed DraBot, the robot is modeled after a dragonfly and is propelled by air pushed out of its front wings while inflated balloons under its back wings allow the team to control its direction. It has a 2.2-inch long body and its wingspan is no longer than 1.4 inches.
As explained by Interesting Engineering, the DraBot moves by controlling the air pressure coming into its wings, where microchannels then move the air into the front wings before it is pushed back through holes and into the back wings. Balloon actuators under its back wings also allow for better control: when these are inflated, the wings curl upwards, and by controlling which wings move up and down, the team can stir DraBot in the direction it wants.
By adding a self-healing hydrogel to one set of the robot’s wings, the team enabled the DraBot to react to changes in its environment, specifically changing pH levels. As a result, if a higher level of acidity is detected in the water, the robot would spin in circles above that area. What’s more, DraBot can detect oil through sponges under its wings as well as change colors according to shifts in temperature.
Although the robot is still in its proof-of-concept stages, it has real potential to soon help disaster responders with long-distance environmental assessments, including detecting oil spills early on and noticing where coral bleaches occur the most.