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TECHIN 517 - ROBOTICS LAB II

ROS BASICS

WEEK 2 | WEDNESDAY | APR 6, 2022

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BASICS

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www.ros.org

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NODES

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NODES

Robot wheel

controller

Kinect driver

GUI

INPUT

OUTPUT

INPUT &

OUTPUT

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NODES

Robot wheel

controller

Navigation

algorithm

Kinect driver

Person

detection

algorithm

Object

detection

algorithm

GUI

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NODES

Robot wheel

controller

Navigation

algorithm

Kinect driver

Person

detection

algorithm

Object

detection

algorithm

GUI

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Kinect driver

Person

detection

algorithm

Object

detection

algorithm

Messages

SERVER

CLIENT

CLIENT

  • “servers publish messages onto topics”
  • “clients subscribe to topics”
  • “messages have msg types”

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SERVER

CLIENT

  • “client requests a service”
  • “server responds to the request”
  • “services have srv types”
  • “servers advertise available services”

Services

get_nearest_person(..)

Navigation

algorithm

Person

detection

algorithm

person_distance

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Robot wheel

controller

Navigation

algorithm

SERVER

CLIENT

Actions

  • “client requests an action”
  • “server performs action and responds”
  • “servers advertise available actions”
  • temporally extended callback, can send feedback during action

move_forward(2.0, 0.5)

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