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Review: Mechanical Devices

Kevin Ross

I recently received an automated email from www.amazon.com that told me about a book that I might be interested in. Apparently they keep records, and based on books I had bought previously, they determined that the subject material might be interesting to me. Well, they were right!

Based on the description sent, I ordered the book they suggested:

Mechanical Devices for the Electronics Experimenter
By Britt Rorabaugh
TAB Books
Paperback, 232 pages
ISBN 0-07-053547-7

It showed up a within a few days, and I tore right in. The premise of the book is that electronic experimenters, especially those who are into building robots, have access to plenty of electronics information, but a little in the way of good mechanical information. This book attempts to fill the need for good information about mechanical design.

The book starts out with a whirlwind tour of various fundamental measures, calculations, and mechanical concepts, such as force, mass, acceleration, etc. He manages to present this information in a reasonable format and at a reasonable pace. While you won't end up being a physics major by reading the first couple of sections, it does provide a solid basis for the discussions found later in the book. Overall, it is a concise and practical explaination of the basics, focusing on the things you need to know.

Subsequent sections are all well written, concise, and focus on concepts that are easy to grasp. I found all of the material to be good practical knowledge for anyone building an electro-mechanical device. He does a good job explaining the very basics of control systems, making the distinction between open-loop and closed-loop designs. He does a good job describing how motors work, and various ways of controlling them and measuring their characteristics. A good explaination of stepper motors is also included.

Other sections include gears, pulleys, springs, hydraulics, pneumatics, and a variety of other useful topics. Each topic explains enough to get you going on your own design. Most include practical design examples, and show you how to make important calculations. For example, how to calculate the sizes of O rings required to build various sizes of pneumatic pistons.

I thought the book was a pretty good read, and it left me with a better understanding of how to approach the design of different mechanical systems. The book doesn't provide many complete design examples, but that wasn't the point of the book.

I highly recommend this book.