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EECS/BioE/ME 106A/206A

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Labs 7 & 8

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Roadmap (Module C)

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This Week (10/28-11/1)

Labs 5 and 6 Due

Start Labs 7 and 8

Start Thinking about Final Project

Two Weeks (11/11-11/15)

Buffer week

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Next Week (11/4-11/08)

Continue Labs 7 and 8

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Three Weeks (11/18-11/22)

Labs 7 and 8 Due�Midterm II

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Reminders

  • Only attend your assigned lab section
    • If you aren’t feeling well, don’t come to lab
  • Keep your stations clean and wipe before use
  • Don’t work in the lab alone
    • Should be working in groups of 2 anyways
  • HAVE A HAND ON THE E-STOP - 1 gripper kaboom
  • USE ZERO-G MODE
    • you should not need to push the arm to move it
  • Use Ctrl+C, exit, and pkill -u $(whoami)

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Lab 7

Full Stack Robotics - Baxter Sawyer

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Goals

Checkpoint 1

  • AR Tracking
  • Line and Circle Trajectories

Checkpoint 2

  • Implement Feedforward and PID Controllers!

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ACTION SERVER

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MOveit ros package

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Lab 5

Lab 7

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Lab 8

Full Stack Robotics - Turtlebots!

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Goals

Checkpoint 1

  • Working perception module

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Checkpoint 2

  • Working trajectory planner

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Checkpoint 3

  • PID controller
  • Integration

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Perception Module

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Trajectory planner - smooth curve

Algorithm:

Given: (x1, y1, theta1) and (x2, y2, theta2)

1. Calculate direction vector based on yaw

2. Determine control points (you can specify the number of points you want, 10 by default) based on yaw (and an arbitrary offset of 0.1, but you can specify that value as well)

3. Sample points along the Bezier curve

4. Determine orientation at each point

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Lab 7 + 8

PID Control Theory & Reminders

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FEEDFORWARD (open LOOP) control

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PID control

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Important Information

Lab 7:

  • Be ready to press E-Stop button
    • Will most likely hit the wall
  • Make sure connect to the robot before executing plan
  • AR Tags are on the table
  • Look at the planned trajectory in RViz before executing (IMPORTANT TO CHECK)
  • Restart trajectory and moveit if CONTROL_FAILED (IN THAT ORDER)

Lab 8:

  • Using the green cups on the stations
  • Using the realsense camera
  • Be careful with running your perception module on the turtlebot
    • It takes a lot of compute & drains battery quickly!
  • Check the trajectory of the robot to ensure it won’t bump into any objects

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Any questions?

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