ORCA Robot Simulator HY475 Autonomous Robot Navigation Introduction

ORCA Robot Simulator HY-475 Autonomous Robot Navigation

Introduction • Originally created by Harris Mpaltzakis. • Useful tool for the verification of algorithms and methods. • Provides the core on top of which various modules can be built and tested. • Provides a visualization mechanism which facilitates verification. • For the course needs you can use features such as: • • Simulation of sensor measurements: laser, sonar, bumpers etc. Ground truth (for debugging and evaluation) Embedded motion control Visualization

Architecture • 3 -tier architecture: • Proxy server. • User module (client). • Simulator (client) TCP/IP protocol used for the connection and communication between tiers

Simulator • The simulator can: • Receive motion commands. • Send measurements. • Given: • An environment. • A motion command. • Provides measurements and simulates real states, such as noise.

Proxy Server • The simulator communicates with modules only via a proxy server. • The proxy server is responsible to control traffic from and to the simulator. • The proxy receives commands from the modules and forwards them to the simulator. • Whenever measurements are available, the simulator sends them to the proxy, which is responsible to forward them to the appropriate modules. • Each module which needs data from the simulator needs to inform the proxy.

User modules • The user module lies at the other end of the communication schema. • In order to communicate with the simulator it first needs to subscribe its “interest” to the proxy. • A user module can: • Send motion commands to the simulator. • Receive, whenever available, measurements from the simulator. • Different modules can ask for different measurements. • Modules don’t need to receive all available measurements (but only the required instead).

General Instructions • Download and install ORCA • http: //www. csd. uoc. gr/~hy 475/orca_setup. exe • Study carefully packet structure in orca_com. ini • Also described in orca_com. pdf • Experiment with map generation (optional) • default shortcut indicates the used environment • env. rigid 3 d. ini describes map geometry • Study provided samples for Java and C • Online demo