The JAviator: A High-Payload Quadrotor UAV with High-Level Programming Capabilities∗

We present the JAviator (Java Aviator), a high-performance quadrotor model helicopter that is built around a high-integrity frame, which is horizontally and vertically symmetric, and supports high payloads through light-weight materials and advanced brushless motors. The JAviator is 1.3m in diameter, weighs 2.2kg in total, and generates a maximum lift of 5.4kg, which translates into a theoretical maximum payload of 3.2kg. Without payload the maximum flight time is around 40min. The JAviator may be programmed in Java using a real-time extension called Exotasks. As an alternative to Java threads, Exotasks enable time-portable programming of high-performance, hard real-time applications in Java. With Exotasks we are able to fly the JAviator using different hardware platforms and software workloads without changing any of the application-level real-time software. The JAviator also serves as a test platform for other software projects such as our own realtime operating system called Tiptoe, which is in a prototypical stage and meant to provide even stronger forms of time portability than Exotasks. Tiptoe supports the execution of real-time processes whose temporal behavior, even including system-level aspects such as their I/O communication and memory management, can be predicted per process, independently of the other processes. The paper describes the JAviator’s hardand software design in detail and reports on propulsion, flight, and software tests.