# Constructionism in Practice: Designing, Thinking, and Learning in a Digital World

By Yasmin Kafai; Mitchel Resnick | Go to book overview

back-based control rather than open-loop control, I wrote an additional chapter of the course notes for the Robo-Cup students that explained the differences and trade-offs between open-loop and feedback-based control. I also discussed the need for calibration of sensor values to local conditions.

A number of students became fixated on using feedback control in surprising ways, however, spending a considerable portion of development time creating a feedback controller to make their robot able to drive in a straight line. Here is how one student explained his system:

The robot is now able to drive in a straight line thanks to its optical shaft encoders. The software continually samples both left and right sensors and adjusts the exact power level to the motors to compensate for any fluctuations in the motion of the robot. The algorithm itself is a combination of differential analysis and Newton's method, along with an "adjustable window" of correction. Simply stated, analyzing differentials gives a reasonable algorithm for adjusting the power levels of the motors, and the adjustable window minimizes excessive wobbling. This algorithm gives us as much accuracy as the resolution of the shaft encoders permits, while keeping wobbling reasonably low. ( Martin, 1994, p. 143)

The ability to drive perfectly straight, however, often does little to help a robot in its overall ability to solve the contest task. Although the activity of driving straight is based on negative feedback control, a strategy that employs this ability in a central way should be considered open-loop at the next higher level, as the robot would be performing a task with little feedback from the crucial environmental features! Therefore, these students' belief that they were using the preferable feedback control was misguided.

Taken as a whole, the collection of biases revealed in students' thinking suggests important misconceptions and misunderstandings about what are effective ways to build reliable real-world systems.

ANALYSIS AND CONCLUSIONS

The examples in this chapter illustrate that students who participate in the robot design course have a variety of preconceptions about systems and control. These ideas are formed by experiences in the traditional academic curriculum and warrant examination specifically because they are not particularly effective when applied to the robot design task.

In the section entitled Robotic Control, we saw how many students have trouble seeing the contest task from a robot-centric perspective, and instead imagine the task from their own omniscient perspective. This naiveté is tempered when they try to put their ideas into being and realize that the robot's point of view is very different from their own.

-318-

If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
One moment ...
Default project is now your active project.
Project items
Notes

#### Cited page

Style
Citations are available only to our active members.
Buy instant access to cite pages or passages in MLA 8, MLA 7, APA and Chicago citation styles.

(Einhorn, 1992, p. 25)

(Einhorn 25)

(Einhorn 25)

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

#### Cited page

Constructionism in Practice: Designing, Thinking, and Learning in a Digital World

• Title Page iii
• Contents vii
• List of Contributors xi
• Introduction 1
• Acknowledgments 8
• Part I - Perspectives in Constructionism 8a
• 1 - A Word for Learning 9
• References 24
• 2 - Perspective-Taking and Object Construction 25
• Conclusion 32
• Acknowledgments 34
• References 34
• 3 - Elementary School Children's Images of Science 37
• Introduction 37
• Conclusions 62
• Acknowledgments 64
• Acknowledgments 65
• Appendix B - Image of Science Interview Guideline 65
• Part II - Learning Through Design 70a
• 4 - Learning Design by Making Games Children's Development of Design Strategies in the Creation of a Complex Computational Artifact 71
• Conclusion 93
• Acknowledgments 94
• References 94
• 5 - Electronic Play Worlds 97
• Conclusions 119
• Acknowledgments 121
• References 121
• 6 - The Art of Design 125
• Foreword 125
• References 158
• 7 - Building and Learning with Programmable Bricks 161
• Introduction 161
• References 172
• Part III - Learning in Communities *
• 8 - Social Constructionism and the Inner City Designing Environments for Social Development and Urban Renewal 175
• Introduction 175
• Acknowledgments 204
• Appendix - Statistical Data About the Four Corners Neighborhood 204
• References 205
• 9 - The MediaMOO Project Constructionism and Professional Community 207
• Conclusion - Constructionism and Virtual Reality 220
• Acknowledgments 221
• References 221
• 10 - A Community of Designers Learning Through Exchanging Questions and Answers 223
• Introduction 223
• References 239
• 11 - They Have Their Own Thoughts 241
• Introduction 241
• Conclusion 251
• Acknowledgments 252
• References 253
• Part IV - Learning About Systems 254a
• 12 - New Paradigms for Computing, New Paradigms for Thinking 255
• Introduction 255
• Acknowledgments 266
• References 267
• 13 - Making Sense of Probability Through Paradox and Programming A Case Study in a Connected Mathematics Framework 269
• Introduction 269
• Concluding Remarks 290
• Acknowledgments 292
• References 293
• 14 - Ideal and Real Systems 297
• Introduction 297
• Analysis and Conclusions 318
• Acknowledgments 322
• References 322
• Author Index 323
• Subject Index 329
Settings

#### Settings

Typeface
Text size Reset View mode
Search within

Look up

#### Look up a word

• Dictionary
• Thesaurus
Please submit a word or phrase above.

Why can't I print more than one page at a time?

Help
Full screen
Items saved from this book
• Bookmarks
• Highlights & Notes
• Citations
/ 340

### How to highlight and cite specific passages

1. Click or tap the first word you want to select.
2. Click or tap the last word you want to select, and you’ll see everything in between get selected.
3. You’ll then get a menu of options like creating a highlight or a citation from that passage of text.

## Cited passage

Style
Citations are available only to our active members.
Buy instant access to cite pages or passages in MLA 8, MLA 7, APA and Chicago citation styles.

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn, 1992, p. 25).

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences."1

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

## Thanks for trying Questia!

Please continue trying out our research tools, but please note, full functionality is available only to our active members.

Your work will be lost once you leave this Web page.