turtlesimjs

turtlesimJS for ROS with almost identical features of turtlesim

Examples

An example

Usage

Pre-built files can be found in either turtlesim.js or turtlesim.min.js.

Installation

In html, add

<script src="build/turtlesim.js"></script>

and

<canvas id="world" width="500" height="500"></canvas>

In command line, run roscore

roscore

, rosbridge

roslaunch rosbridge_server rosbridge_websocket.launch

, and turtle_teleop_key

rosrun turtlesim turtle_teleop_key

. Just like running turtlesim, you can use turtle_teleop_key to control turtlesimJS.

APIs

Create a turtlesim

var turtlesim = new TURTLESIMJS.TurtleSim({
	// a ros instance
	ros			: ros,
	// the context of the HTML canvas
	context		: context,
	// if the turtle can be controlled by keyboard
	keyControl	: true,
	// the background color
	fill		: "#4556FF",
	// the interval to update the turtlesim
	interval	: 100
})

Some items can be ignored.

Create a turtle

turtlesim.spawnTurtle({
	// a unique name for the turtle
	name		: 'turtle1',
	// initialize pose
	pose		: {
		x		: width / 2,
		y		: height / 2,
		theta	: 0
	}
	// pen for trajectory
	pen			: {
		color	: "#b3b8ff",
		width	: "3",
		off		: false
	},
	// image for a turtle
	img			: "a random turtle image.png"
})

Some items can be ignored.

Subscribed Topics

turtleX/cmd_vel (geometry_msgs/Twist)

The linear and angular command velocity for turtleX. The turtle will execute a velocity command for 1 second then time out.

Published Topics

turtleX/pose (turtlesim/Pose)

The x, y, theta, linear velocity, and angular velocity of turtleX.

Services

It mimics the services provided by turtlesim. Unfortunately roslibjs does not provide APIs to create a service, so the following functions do not work.

clear

Clears the turtlesim background and sets the color to the value of the background parameters.

reset

Resets the turtlesim to the start configuration and sets the background color to the value of the background.

kill

Kills a turtle by name.

spawn

Spawns a turtle at (x, y, theta) and returns the name of the turtle. Also will take name for argument but will fail if a duplicate name.

turtleX/set_pen

Sets the pen's color (r g b), width (width), and turns the pen on and off (off).

turtleX/teleport_absolute

Teleports the turtleX to (x, y, theta).

turtleX/teleport_relative

Teleports the turtleX a linear and angular distance from the turtles current position.

Parameters

/background_b

Sets the blue channel of the background color.

/background_g

Sets the green channel of the background color.

/background_r

Sets the red channel of the background color.

Dependencies

turtlesimjs depends on:

EventEmitter2, roslibjs.

License

turtlesimjs is released with a BSD license. For full terms and conditions, see the LICENSE file.

Acknowledgement

This project follows the idea of turtlesimjs, and it mimics turtlesim.