Abstract Systematic testing of autonomous vehicles operating in complex real-world scenarios is a difficult and expensive problem. We present Paracosm, a framework for writing systematic test scenarios for autonomous driving simulations. Paracosm allows users to programmatically describe complex driving situations with specific features, e.g., road layouts and environmental conditions, as well as reactive temporal behaviors of other cars and pedestrians. A systematic exploration of the state space, both for visual features and for reactive interactions with the environment is made possible. We define a notion of test coverage for parameter configurations based on combinatorial testing and low dispersion sequences. Using fuzzing on parameter configurations, our automatic test generator can maximize coverage of various behaviors and find problematic cases. Through empirical evaluations, we demonstrate the capabilities of Paracosm in programmatically modeling parameterized test environments, and in finding problematic scenarios.

Abstract Parametric computer‐aided design (CAD) enables description of a family of objects, wherein each valid combination of parameter values results in a different final form. Although Graphical User Interface (GUI)‐based CAD tools are significantly more popular, GUI operations do not carry a semantic description, and are therefore brittle with respect to changes in parameter values. Programmatic interfaces, on the other hand, are more robust due to an exact specification of how the operations are applied. However, programming is unintuitive and has a steep learning curve. In this work, we link the interactivity of GUI with the robustness of programming. Inspired by programme synthesis by example, our technique synthesizes code representative of selections made by users in a GUI interface. Through experiments, we demonstrate that our technique can synthesize relevant and robust sub‐programmes in a reasonable amount of time. A user study reveals that our interface offers significant improvements over a programming‐only interface.

Automated controller synthesis methods for cyber-physical systems (CPSs) often require precise knowledge of the system's state. Unfortunately, parts of the state may not be directly measurable, which limits the application of these methods. We present a design methodology for the co-design of software controllers and the required sensing capabilities. Our method leverages the knowledge of physical units in the model of a system to find ways of indirectly measuring parts of the system's state which cannot be measured directly. The method contains a search procedure which uses dimensional analysis to explore the space of physically well-typed expressions and it generates as an intermediate result possible sensor combinations. The integration between the physical and software design for CPS that we present make automated controller synthesis techniques more widely applicable. We have implemented our method and applied it to the design of robotic manipulators.

Robotics applications involve programming concurrent components synchronising through messages while simultaneously executing motion primitives that control the state of the physical world. Today, these applications are typically programmed in low-level imperative programming languages which provide little support for abstraction or reasoning. We present a unifying programming model for concurrent message-passing systems that additionally control the evolution of physical state variables, together with a compositional reasoning framework based on multiparty session types. Our programming model combines message-passing concurrent processes with motion primitives. Processes represent autonomous components in a robotic assembly, such as a cart or a robotic arm, and they synchronise via discrete messages as well as via motion primitives. Continuous evolution of trajectories under the action of controllers is also modelled by motion primitives, which operate in global, physical time. We use multiparty session types as specifications to orchestrate discrete message-passing concurrency and continuous flow of trajectories. A global session type specifies the communication protocol among the components with joint motion primitives. A projection from a global type ensures that jointly executed actions at end-points are communication safe and deadlock-free, i.e., session-typed components do not get stuck. Together, these checks provide a compositional verification methodology for assemblies of robotic components with respect to concurrency invariants such as a progress property of communications as well as dynamic invariants such as absence of collision. We have implemented our core language and, through initial experiments, have shown how multiparty session types can be used to specify and compositionally verify robotic systems implemented on top of off-the-shelf and custom hardware using standard robotics application libraries.

Building small custom robots is getting democratized thanks to affordable tools like 3D printers and micro controllers. However, it still requires expertise from a wide range of domains: from designing the mechanical parts to writing the code that controls the robot. We present MPERL, a tool to help non-experts build custom robotic manipulators. MPERL starts from an abstract description of the robot's kinematic structure which contains information about joints, actuators, and sensors. The structure is refined with an easily manufactured geometry. Furthermore, from the structure MPERL generates control code which can be used to move the robot to a target configuration. We evaluate MPERL on a range of common robotic manipulator architectures, both serial and parallel.