Some more information is needed to make a practical suggestion, depending on the situation the obvious answer is set up opposite the wall, shoot an array along the bottom and then stake out that array at the top to compare but depending on circumstances there can be complications.
Hate to say it, but, string don't lie; I would consider hanging a plumb bob at some distance like .3 out from the wall at the top, measure a miss to the face of wall at the top and bottom. Shoot location for the drawing and note in the departure.?ÿ
@jaro25'
@dave-lindellI tried to use vertical grid scan in survce. Set the tolerance to 0.04 but angle of incidence causes problems with steep vertical angles in the ballpark up to 0.25'. I can't setup far enough from the
face of the wall.
Set up as far away as possible, maybe more than one set up, to keep angles low. Shoot to a 360 prism, preferably robotic autotracking, held against top and base of wall - use those vertical formwork lines to get the same position.?ÿDistance from the prism center to the wall should be the same regardless of position/angle?
From the looks of it, I would mark stations on top of the wall at whatever interval is necessary. Then cut a kerf in the end of a 2x4 to hold a plumb bob string, nail a block on the bottom of the 2x4 so that when laid on top of and perpendicular to the wall the string would be a foot (or whatever distance is handy) from the wall. Have somebody at the bottom to steady the plumb bob and take a measurement from the string. Thats the cheap route. Could use some aluminum tubing instead of a 2x4 to fancy it up a little bit.?ÿ
I think I would traverse along that wall - if it is an OSHA ok'd activity, given that fill slope.
The economy of set-ups, options and freedom when you're down there, and the accuracy you could achieve with a 25' prism pole, and a Seco mini-prism with sight vanes, on the balance look like the best bet.
Saying that from only looking at one photo though.
Perhaps this might be a job for using a "Smart Level?" Years ago, I used one for determining sidewalk slopes. It did what was needed and it was fast.
?ÿ
Once upon a time, we surveyed a large curved theater screen as they were interested in correcting larger variations from the radius. So, we took a ton of shots and calculated the center.?ÿ Then inversed from the radius point to all the points shot and used those inverses as a "z" value and contoured the screen. A tight contour interval showed all the variations very well.?ÿ
the picture helps...
Another idea, assuming the top of wall is accessible.
Set a something at the base of the wall at intervals along the wall - could be a vertical 2x4 with a scrap of plywood nailed on top.
Mark a spot on the plywood, say 2 inches off the face of the wall. Use a PLS-5 type vertical laser and set it over the mark. At the top of the wall, measure the distance the vertical laser is from the wall.
I've been using Microsurvey to process point clouds, it is vastly better than Cyclone. ?ÿIf you had a point cloud you don't have to model the wall. You can set up a vertical reference plane perpendicular to the wall, turn on osnapz then using a node snap draw a 3D polyline up the face of the wall. It will automatically draw the line on the reference plane. They have a video online describing how to do it to make a road profile. You could do that every 5 feet or whatever interval floats your boat. Cyclone has a 2D drawing tool that does the same thing but it doesn't snap, it is just by eyeball like tracing what you see.
At that height I would use a 64 oz plumb bob and a bucket of water on a very calm day.
James
I would shoot and mark stations at the bottom of the wall. then use a ladder, a jig or carpenters square at he top of the wall hanging a heavy plumb bob to the bottom and measure the plumb differences from top and bottom. Simple quick and repeatable. Saves the nightmare of complicated transfer into cad. Without all this wanting to do all those high-tech equipment and software approaches you could have been done by now. 😯 ?ÿ
KISS, an acronym for "keep it simple, stupid" or "keep it stupid simple", is a design principle noted by the U.S. Navy in 1960. The KISS principle states that most systems work best if they are kept simple rather than made complicated; therefore, simplicity should be a key goal in design, and unnecessary complexity should be avoided. 😉 ?ÿ
