Acoustokinetics: Crafting force landscapes from sound waves

The acoustokinetic framework expresses the acoustic radiation force acting on a small object in terms of the amplitude and phase profiles of the incident sound wave. This formulation clarifies how to control the conservative and nonconservative forces exerted by sound and how to design structured sound waves that trap, twirl and transport objects along arbitrary paths in three dimensions. The authors illustrate the design process by crafting pseudo-standing waves, alternating picket-fence force fields, and propagation-invariant tractor beams.