Robot Doctor

The Basics of Robotics: The What, Why and How, with Examples and Take-home Problems

WQED and RobotWits are partnering to provide this educational video series that extends robotics and mathematics lessons to high school age students during the COVID-19 crisis. The series will be available on this site, and televised on WQED-TV Wednesday nights at 7:30pm through June 24, 2020. Pennsylvania’s other public television stations will also broadcast the series. Please check the schedules at WHYY, WITF, WLVT, WPSU, WVIA and WQLN for dates and times.

RobotWits LLC is providing educators content-related support and partnering with PA Rural Robotics to assist educators in planning and customizing content to complement their school district, students, and community needs. The series will be available to all public television stations in Pennsylvania so that the programs can reach rural as well as urban audiences, where Internet access can sometimes be a challenge.

Hosted by Dr. Jonathan Butzke, each of the eight 14-minute teaching videos includes a lesson assignment. Participating teachers can use the series to collect the assignments and make The Robot Doctor part of their curriculum.

Lesson 101 - Robotics: An Introduction
This video focuses on design elements: locomotion, end-effectors, appearance - and how they relate to a robot’s purpose.

assignment lesson 101

1. Choose a task for your robot to complete.
2. Choose the design elements. What does your robot need to get its job done?
3. Explain how the design elements help the robot do its job.
4. Choose a different task and compare design elements.

Open PDF Handout

Lesson 102 - Sense, Plan, Act Framework
How a robot can break down its tasks into sensing the surroundings, planning what to do next, then executing the plan.

Assignment 102

Imagine you have a robot surveying an orchard, looking for ripe fruit to pick. 
1. What are the sense, plan, and act steps for this robot?
Imagine you have a robot vacuum cleaner.
2. What are the sense, plan, and act steps for this robot?
What do they need to sense? What kind of plan would they need to make? What are their actions?
3. Explain the steps that are similar, and the steps that are different between the two robots, and why.
4. How does the plan change when we use "lowest energy" instead of "fastest time?"

Open PDF Handout

Lesson 103: Robot Measurement
An exploration of the different ways to measure distances, speeds, time, and other items important to robots.

1. How long will it take for a robot sensor to get a return pulse?

  • Distance = 10 meters
  • Speed of sound = 343 meters/second

2. How high is the table the end effector must reach to grab the object?

  • Arm length = 50cm
  • Arm angle = .5 radians 

Open PDF Handout 

Lesson 104: Robot Localization
Keeping track of position as a robot moves, and updating that position with math using ranges to known landmarks.

  1. If our robot is 5 meters from the tree (2, 13), 10 meters from the bush (13,11) and 5 meters from the pond (5,22), where is it?
  2. Now imagine the robot sees two landmarks, a pile of rocks (10,0) and an umbrella (20,0). The distance to both objects is 5 meters. Can you still determine the position of the robot?

Open PDF Handout

Lesson 105: Robot Motion
How a robot moves, using math to predict future positions - given the robot’s model and the equations of motion.

Imagine you have a robot that is 50cm wide, with a wheel radius of 10cm, starting at (0,0), with an orientation of π/4.

  1. If both wheels move at 1 radian/second for 10 seconds, what is the robots final position and orientation?
  2. If the right wheel moves at 1 radian/second and the left wheel at 1.5 radians/second, what is the orientation after 1 second?

Open PDF Handout

Lesson 106: Robot Vision
How a robot can sense the world it around it using cameras, determining the distance to objects using two cameras.

  1. If a feature on an object is located at an x-coordinate of 3000 on the left camera and at an x-coordinate of 1000 on the right camera, how far in front of the robot is the object?
  2. Why does the accuracy of this method become worse as the objects move farther away? It may help to think about what the distance is if the objects are 1 pixel from the center versus 2 pixels from the center.

 

Lesson 107: Robot Sensing and Mapping
How a robot can “see” things around it without using cameras - converting polar coordinates to cartesian coordinates in order to make a map.

Start with a 3m by 3m grid with 1m cells as shown. The robot is in the center of the bottom left cell. Initially the map has a value of 50% for all cells. Use: p(return|obstacle) = 80%, p(return|clear) = 10%

  1. The robot gets a lidar return from the bottom right cell – Which cells will have a change in value?
  2. What are the updated values for each cell?
  3. If the robot gets a second return from the bottom righ cell, what are the updated values now?

Lesson 108: Robot Controls
How we can control a robot’s motors in order to follow a line, including a curved line.

Our robot wants to follow a diagonal line starting at (0,0), going through the origin and a point at (10,10).

  1. If the robot is at (2,3), how far away from the line is the robot? And on which side of the line is the robot?
  2. If the proportional gain is 15 degrees per meter, what is the commanded steering angle from the controller?

Dr. Jonathan Butzke
The Robot Doctor is hosted by Dr. Jonathan Butzke, Lead Robotics Researcher at RobotWits, a Pittsburgh-based company that develops state-of-the-art technologies for a diverse set of autonomous decision making tasks. Dr. Butzke obtained his Ph.D. in Robotics from Carnegie Mellon University where he worked in the Search-Based Planning Lab. His research activities include aerial and ground vehicle coordination, exploration of unknown environments, and the hardware design of numerous robots.