Dynamically-Controllable Nozzle for Precision Agricultural Spraying

Rapid advancement in pesticide application includes robotics autonomous vehicles and unmannedaircraft; yet these systems still rely upon and are limited by existing legacy spray nozzles.The goal of the project is a controllable nozzle with deformations of the exit orifice providingcontrol of the spray flow pattern droplet size and motion.The nozzle materials and properties willbe designed to allow simple actuation by piezo-active elements providing low-cost low powerconsumption rapid response and low mass.Piezo-electric actuators for human interface haptics(e.g. mobile phone keyboard feedback) have high durability long life and low cost.Theperformance goals of the nozzle system are a greatly expanded 3-D control space (flow rate dropletsize and spray pattern and velocity) a ten-fold reduction in actuator mass and power requirementsand ten-fold increase in response time.The novel aspects are: a) A deformable nozzle shape with heterogeneous material propertiesallowing orifice shape deformations to alter spray formation; b) Low mass low power piezoelectricactuators; c) Nozzle design to translate linear actuation to curvilinear alterations in the orificeshape; d) Actuators to allow spray aiming; and e) Integration into industry standard pressure andPWM control systems to achieve defined spray characteristics such as flow rate droplet size sprayvelocity and spray pattern.The final system will address the unique needs of modern precision agriculture spray systems suchas precision target-sensing weed sprayers and unmanned aircraft; yet it will also be compatiblewith and provide new capabilities for conventional ag aprayers.