Point to Point: Computer-Assisted Surveying

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Personal computers have fundamentally changed how we work–for the better, I believe. I don’t see where they have reduced the time spent in getting projects completed, however. From my experience, the work effort itself is more complex and precise, and more refinement takes place, but the time necessary to get jobs out the door remains fairly constant.

I don’t intend for this to be an indictment of computers in surveying or computers in general. Indeed, anyone who knows me at all knows that I am basically a computer nerd; give me a malfunctioning PC and I’ll happily wile away hours trying to fix it. But it is useful occasionally to examine our work products, our tools, and our approach to both.

Few would now dispute the widespread utility of computers in surveying; there seems to be no significant task that they do not materially enhance. Personally, I’m delighted. Gone are the days of drudgery immersed in long-hand calculations. Matte never gets inadvertently erased from Mylar anymore. We are on the cusp of dramatic improvements to property research, field data processing is a snap, and plats can be more beautiful than ever. This is good stuff.

I think there is something else going on as well, though, and I can’t decide whether it is a good thing or not.

The Bridge
Some years ago I had occasion to review the construction documents for a bridge over an interstate highway near here. This particular bridge, having been designed and constructed in the 1950s, was a two-lane multi-span design, crossing the four lanes and median of the interstate. (We were interested in the construction documents to recover the original baseline of construction, which in turn would allow us to reproduce the right-of-way lines for the intersection. Why we might use that particular method of retracement is outside the scope of this essay.) The reason for our present interest is because the construction drawings for that bridge consisted of one sheet. Plan and profile. Sometime later I happened to be chatting with the Director of the Bureau of Engineering of our state highway department, and mentioned the one-sheet bridge. I expressed surprise and wondered how anything so complex could have been accomplished so succinctly. He chuckled in agreement and noted that the explosion in required drawings for major highway construction mysteriously coincided with the explosion of CAD use. The same bridge probably could not be approved for construction using less than 80 sheets today. He was convinced that, like the relation of the size of goldfish to the size of the tank, design requirements grow in proportion to our ability to comply with them. Put another way, if the design of the bridge formerly took eight man-weeks, the design time assisted by computers will still take eight man-weeks. (And result in a blizzard of paper as well!)

There is thus more going on here than simply automating tasks. Our presumption as to what is acceptable practice is evolving. Because the PC frees us to accomplish more, more is expected. But is that right? After all, that bridge is still standing these 50 years later; from that perspective the one-sheet process is hard to condemn.

Cognitive Interaction
Because the deployment of computers onto everyone’s desk is a relatively recent development, there has not been much research to date concerning human cognitive interaction with the machines. (In the interest of clarity, I should note that there has been a great deal of research into repetitive task productivity, and plenty of ergonomic studies. I am focusing here on the subtle ways we humans alter our view of getting the job done with the assistance of PCs.) For "knowledge workers," and that would include nearly everyone in a modern surveying firm, the anecdotal evidence has always been that the introduction of computers into the workplace would not result in a loss of jobs, but that the jobs would evolve. (This, in contrast to previous forms of automation. EDMs, for example, eliminated the jobs of countless chainmen, and as a result survey crews on average are much smaller than they were twenty years ago. Robotics will have a similar effect.) Indeed, nearly every job did evolve, to the point now that when power is off for any length of time, we close the office and send everyone home. Given the computer cycles thrown at any task today as compared with those of twenty years ago, we should be cranking out 100 times the number of projects. That is not happening.

I’m not suggesting, of course, that computers actually slow the cognitive process; anyone who remembers the steps required to compute D.M.D. areas knows that using COGO software beats the old way hands down. But I see evidence that the calendar time necessary to accomplish tasks stays roughly constant despite the tools used. Digital topography, for instance, gets refined on screen to a much greater extent than hand-plotted stadia topography ever did. Our audience expects more from the digital deliverable. Does that mean that topography from 50 years ago was not fit for its audience? One could not conclude so considering the explosion of development following the Second World War–for the most part based on that hand-plotted stadia topography!

A Bridge Too Far
It’s important to recognize that even if our time-on-project is longer than it could be, it is not necessarily wrong. My ability to study other alternatives in a boundary analysis because I have the time to do so should result in a more thorough analysis. And I am glad for the opportunity. But am I designing an 80-sheet bridge where one sheet would suffice?

Despite the twenty-somethings having grown up with them, we are still at the dawn of the personal computer age. No one yet knows how we will integrate these machines into our thought processes. We would do well to recognize, however, that we have already changed as a result of their presence, and will continue to do so.

Joel Leininger is a principal of S.J. Martenet & Co. in Baltimore and Associate Editor of the magazine.

A 1.269Mb PDF of this article as it appeared in the magazine complete with images is available by clicking HERE

About the Author

Joel M. Leininger, LS

Joel Leininger, Associate Editor of the magazine, is the managing partner of S. J. Martenet & Co., a 154-year-old surveying firm in Baltimore, Maryland. He lectures frequently around the country on surveying-related subjects. Leininger has authored more than thirty articles and essays dealing with surveying and retracement, some of which have been published in Canada and Australia. Prior to his work at S.J. Martenet, he served as department head at Fisher, Collins and Carter, and as project manager with Daft-McCune-Walker, both in Baltimore. Leininger has also served as both Contributing Editor and Associate Editor of Professional Surveyor Magazine. He served five years on the Maryland Board of Registration and is a past-president of the Maryland Society of Surveyors. Contact Joel Article List Below