https://www.digitaltrends.com/cool-tech/ionocraft-tiny-flying-robot/
wow....
To understand how it works, imagine two asymmetric — [such as] a wire and a plate — electrodes,” Daniel Drew, currently a Postdoctoral Fellow in the Mechanical Engineering department at Stanford University, told Digital Trends. “When a voltage is applied between the two, the electric field will be stronger in the vicinity of the wire as a function of its geometry. If this field is strong enough, an ambient electron can be pulled in with enough kinetic energy to initiate avalanche breakdown through impact ionization. There’s now a stable plasma, glowing purple in the dark, around the top wire. Generated ions will be ejected from this plasma, drifting in the electric field towards the bottom electrode. Along the way, they collide with neutral air molecules and impart momentum, producing a net thrust.”
wow....
To understand how it works, imagine two asymmetric — [such as] a wire and a plate — electrodes,” Daniel Drew, currently a Postdoctoral Fellow in the Mechanical Engineering department at Stanford University, told Digital Trends. “When a voltage is applied between the two, the electric field will be stronger in the vicinity of the wire as a function of its geometry. If this field is strong enough, an ambient electron can be pulled in with enough kinetic energy to initiate avalanche breakdown through impact ionization. There’s now a stable plasma, glowing purple in the dark, around the top wire. Generated ions will be ejected from this plasma, drifting in the electric field towards the bottom electrode. Along the way, they collide with neutral air molecules and impart momentum, producing a net thrust.”