Description

The translator node for calculating the speeds and angles of the 6 wheels and the robot arm

ros2 name: n10_drive_translator_node

launch with :

ros2 launch translator translator.launch.py

Interface

subscribed

• /n10/cmd_vel geometry_msgs::msg::Twist 100 Hz expected : linear and angular velocity of the robot

  • inear.x : from -1 ≐ -1 m/s to 1 ≐ 1 m/s
  • linear.y : from -1 ≐ -1 m/s to 1 ≐ 1 m/s
  • angular.z : from -1 ≐ -π/2 m/s to 1 ≐ π/2 m/s counterclockwise

• /n10/arm_state std_msgs::msg::Float32MultiArray (4) : absolute arm position, ground_angle and grabber state

publishing

• /n10/motor_vel std_msgs::msg::Float32MultiArray (6) 100 Hz : wheel RPMs

  • publishes 0 after 100ms not /n10/cmd_vel recieved

• /n10/servo_cmd_wheels std_msgs::msg::Float32MultiArray (6) 100 Hz : wheel angles

  • from -π/2 ≐ pointing right to π/2 ≐ pointing left

• /n10/servo_cmd_arm std_msgs::msg::Float32MultiArray (4) 100 Hz : arm_joint angles and grabber servo angle

Parameters

Can be set in parameter/translator.yaml

Simulation

• plot/velocity_plot.py for visualization of velocity vectors for the wheels published to /n10/servo_cmd_wheels and /n10/motor_vel

• plot/arm_plot.py for visualization of arm angles published to /n10/servo_cmd_arm