Waypoint ======== This actuator reads the coordinates of a destination point, and moves the robot towards the given point, with the robot restricted to moving only forward, turning around its Z axis, and possibly going up and down. This controller is meant to be used mainly by non-holonomic robots. While a robot is moving towards a given waypoint, a property of the **Robot** will be changed in indicate the status of the robot. The ``movement_status`` property will take one of these values: **Stop**, **Transit** or **Arrived**. The movement speed of the robot is internally adjusted to the Blender time measure, following the formula: ``blender_speed = given_speed * tics``, where **tics** is the number of times the code gets executed per second. The default value in Blender is ``tics = 60``. This actuator also implements a simple obstacle avoidance mechanism. The blend file contains the **Motion_Controller** empty, as well as two additional Empty objects: **Radar.L** and **Radar.R**. These detect nearby objects to the left or right of the robot, and will instruct the robot to turn in the opposite direction of the obstacle. If the radar objects are not present, the controller will not have any obstacle avoidance, and the robot can get blocked by any object between it and the target. .. note:: For objects to be detectable by the radars, they must have the following settings in the **Physics Properties** panel: - **Actor** must be checked - **Collision Bounds** must be checked This will work even for Static objects .. cssclass:: properties morse-section Configuration parameters for Waypoint ------------------------------------- You can set these properties in your scripts with ``.properties(=..., =...)``. - ``ObstacleAvoidance`` (bool, default: ``True``) if true (default), will activate obstacle avoidance if the radars are present - ``FreeZ`` (bool, default: ``False``) if false (default), the robot is only controlled on 'X' and heading; if true, 'Z' is also controlled (for aerial or submarine robots) - ``AngleTolerance`` (float, default: ``0.17453292519943295``) Tolerance in radian regarding the final heading of the robot - ``Speed`` (float, default: ``1.0``) movement speed for the robot, given in m/s - ``Target`` (string, default: ``""``) name of a blender object in the scene. When specified, this object will be placed at the coordinates given to the actuator, to indicate the expected destination of the robot - ``Ignore`` (string, default: ``[]``) List of property names. If the object detected by the radars has any of these properties defined, it will be ignored by the obstacle avoidance, and will not make the robot change its trajectory. Useful when trying to move close to an object of a certain kind - ``ControlType`` (string, default: ``"Velocity"``) Kind of control, can be one of ['Velocity', 'Position'] - ``RemainAtDestination`` (bool, default: ``False``) If true (default: false), the robot actively attempts to remain at the waypoint once reached. This is especially useful for flying robots that would otherwise typically fall. .. cssclass:: fields morse-section Data fields ----------- This actuator reads these datafields at each simulation step: - ``x`` (float, initial value: ``0.0``) X coordinate of the destination, in world frame, in meter - ``y`` (float, initial value: ``0.0``) Y coordinate of the destination, in world frame, in meter - ``z`` (float, initial value: ``0.0``) Z coordinate of the destination, in world frame, in meter - ``tolerance`` (float, initial value: ``0.5``) Tolerance, in meter, to consider the destination as reached. - ``speed`` (float, initial value: ``1.0``) If the property 'Speed' is set, use this speed as initial value. *Interface support:* - :tag:`yarp` as yarp::Bottle (:py:mod:`morse.middleware.yarp_datastream.YarpReader`) - :tag:`socket` as straight JSON deserialization (:py:mod:`morse.middleware.socket_datastream.SocketReader`) - :tag:`yarp_json` as yarp::Bottle (:py:mod:`morse.middleware.yarp.yarp_json.YarpJsonReader`) .. cssclass:: services morse-section Services for Waypoint --------------------- - ``get_properties()`` (blocking) Returns the properties of a component. - Return value a dictionary of the current component's properties - ``stop()`` (blocking) This method will instruct the robot to set its speed to 0.0, and reply immediately. If a **goto** request is ongoing, it will remain "pending", as the current destination is not changed. - ``resume()`` (blocking) Restores the speed to the same value as before the last call to the **stop** service. The robot will continue to the last waypoint specified. - ``get_status()`` (blocking) Ask the actuator to send a message indicating the current movement status of the parent robot. There are three possible states: **Transit**, **Arrived** and **Stop**. - ``get_configurations()`` (blocking) Returns the configurations of a component (parsed from the properties). - Return value a dictionary of the current component's configurations - ``setdest(x, y, z, tolerance, speed)`` (blocking) Set a new waypoint and returns. The robot will try to go to this position, but the service caller has no mean to know when the destination is reached or if it failed. In most cases, the asynchronous service 'goto' should be prefered. - Parameters - ``x``: x coordinate of the destination, in world frame, in meter - ``y``: y coordinate of the destination, in world frame, in meter - ``z``: z coordinate of the destination, in world frame, in meter - ``tolerance``: tolerance, in meter, to consider the destination as reached. Optional (default: 0.5 m). - ``speed``: speed to join the goal. Optional (default 1m/s) - Return value Returns always True (if the robot is already moving, the previous target is replaced by the new one) except if the destination is already reached. In this case, returns ``False``. - ``goto(x, y, z, tolerance, speed)`` (non blocking) This method can be used to give a one time instruction to the actuator. When the robot reaches the destination, it will send a reply, indicating that the new status of the robot is "Stop". - Parameters - ``x``: x coordinate of the destination, in world frame, in meter - ``y``: y coordinate of the destination, in world frame, in meter - ``z``: z coordinate of the destination, in world frame, in meter - ``tolerance``: tolerance, in meter, to consider the destination as reached. Optional (default: 0.5 m). - ``speed``: speed to join the goal. Optional (default 1m/s) - ``set_property(prop_name, prop_val)`` (blocking) Modify one property on a component - Parameters - ``prop_name``: the name of the property to modify (as shown the documentation) - ``prop_val``: the new value of the property. Note that there is no checking about the type of the value so be careful - Return value nothing .. cssclass:: examples morse-section Examples -------- The following examples show how to use this component in a *Builder* script: .. code-block:: python from morse.builder import * # adds a default robot (the MORSE mascott!) robot = Morsy() # creates a new instance of the actuator waypoint = Waypoint() # place your component at the correct location waypoint.translate(, , ) waypoint.rotate(, , ) robot.append(waypoint) # define one or several communication interface, like 'socket' waypoint.add_interface() env = Environment('empty') .. cssclass:: files morse-section Other sources of examples +++++++++++++++++++++++++ - `Source code <../../_modules/morse/actuators/waypoint.html>`_ - `Unit-test <../../_modules/base/waypoint_testing.html>`_ *(This page has been auto-generated from MORSE module morse.actuators.waypoint.)*