ROBOTS ALIVE!: Look, No Hands!
Driving without putting your hands on the steering wheel is not usually recommended, but today it's possible to ride in an experimental van that does the driving for you. For more than ten years, robotics engineer Chuck Thorpe of Carnegie Mellon University in Pittsburgh has been working on a project called Navlab, with the ultimate goal to design and produce a vehicle that drives itself. Using sensors and video cameras, the van navigates highways without a human driver.
Activity 1: Robot Pizza Cutter
Inventing the Future (Show 701): "Virtually Real"
ACTIVITY: ROBOT PIZZA CUTTER
A robot is a device made of two main parts: a mechanical or machine part, and a control device or brain. In simple terms, the Navlab vehicle also consists of these components: a machine (van) and computerized components that read the road and tell the van what to do.
Among the more positive applications of robotics are the many high-tech devices that help disabled people function normally. A few years ago, a design team at Carnegie Mellon University invented Pizzabot, a robotic arm that could make a pizza. With the help of this high-tech chef, a disabled person used voice commands to tell the robot which toppings to put on a pizza.
Surprisingly, a pizza is a complicated product to make. Each step in the pizza-making process must be programmed. Using the algorithm procedure outlined in Activity 1 for Mazes and Squiggles, describe the sequence of steps involved in making a simple pizza.
Now, try to build a pizza using just your voice. By using verbal commands, you will guide a mechanical device over a "pizza" target. The machine is a radio-controlled car with a marking pen attached to it. Since an electronic voice-activated circuit would be too difficult to build and too expensive to buy, we'll use the next best thing -- a human voice. Work in teams of four.
Simulate programming a robotic device.
- radio-controlled car with controller unit
- large sheets of newsprint, each with a circle 2 feet in diameter drawn on it
- permanent marking pen
- Assign each person in the group one of these roles:
Engineer -- figures out how to attach the marker to the R/C car.
Timer -- times each person's turn.
Operator -- directs the movements of the R/C car by voice command; can give only four commands: forward, stop, right, left.
Controller -- the only team member allowed to work the controls of the R/C car; responds only to commands issued by the operator.
- Have the engineer attach the marker to the R/C car so that the marker's point extends beneath the car and makes contact with the floor surface. If attached properly, the marker will leave a trace of the car's path.
- The timer should tape the pizza target to the floor. The engineer should place the modified R/C car in the center of the newsprint circle, making sure the marker remains in contact with the newsprint surface.
- The controller (person holding the control unit) should stand about ten feet from the target, facing in the opposite direction.
- The operator, while facing the target, then gives commands to move the R/C car. The object is for the operator to have the car trace "cuts" onto the pizza target that will result in four equal slices.
- The timer gives the operator three minutes to complete the objective. At the end of three minutes, team members should exchange places, making sure everyone has a chance to perform each of the four roles.
- What limitations in performing the tennis court challenge might a robot have that a human would not have?
- Can you think of ways to revise your program to make the number of instructions as small as possible? What would be the advantage of this? Do artificial intelligence (AI) researchers have to worry about the size of their programs?
Note to Teacher on Setting Up the Challenge:
To conduct this challenge, block off a section of your room with a cardboard barrier that will allow students to observe the robot performing the task but will limit the space so the task is not impossible. A cardboard box with an opening cut in the side can serve as a pen.
In 1995, researchers from the Robotics Lab at CMU "drove" the van seen in this segment (Navlab 5) from Pittsburgh, Pa., to San Diego, Calif., as part of the "No Hands Across America" project. Read about their trip at http://www.cs.cmu.edu/scs/research.html.
CREDIT: This activity was developed by science educator Marc Rosner.
Scientific American Frontiers
Fall 1990 to Spring 2000
Sponsored by GTE Corporation,
now a part of Verizon Communications Inc.