Hi guys. I'm brand new to the forum and was hoping for some help with an issue I'm having. Running a Trimble S6 robot and for some reason when I turn to my backsite it will be out left/right so I know the angle is somehow getting messed up . The error grows the longer I work and was wondering what this could be. Now before you roll your eyes and scream, the gun will still be perfectly level while this is going on. I check the level screen on my tsc2 methodically. I use a timble -35mm backsite kit at all times and I will check that as well to make sure it is still level which it always is. I also have done all of my field calibrations recently, and usually perform them at least once a week with the exception of the compensator calibration which I usually do daily. Was just wondering if anyone has ran into this issue with the S6 and if anyone knew how to fix it or at least minimize this from happening. Today I was setting anchor bolts and it kept going out .02' to the west for some reason about every 15 minutes. Thanks in advance.
I'd be on the phone with my Trimble dealer. Any heavy equipment operating in the area? Gun is very sensitive to any ground vibration. Maybe try turning autolock off and switching to another prism type to try an isolate problem. Good luck.
I actually called my Trimble rep and he didn't have an answer. It was calibrated by keystone precision about 6 months ago as well. The work I'm currently doing requires me to switch between prism types. I set up the -35 for my backsite and leave it there and then do 99% of my work using a -17.5mm mini prism. This error does carry over when switching between prisms. As far as heavy equipment there is more of that around than I can describe however my traverse runs along a ridgeline away from the work site so there aren't any vibrations. Trying to narrow it down has been a real pain. The weird thing is sometimes it works perfectly fine. Just last week I was setup running a resection actually closer to machinery than I usually do and it stayed level for literally 4 hours, turned to the backsite every 15 minutes or so and it was fine. Do you think it could be the tribrach? I use about 3 different tribrachs and switch between them pretty frequently (leap frogging backsites during traveres). They are all the same trimble one though.
Easy enough to find out if it's the tribrach by numbering them or something and see if you can narrow it down to one that has a minute bit of play in it you otherwise wouldn't notice.
Did you run all of the adjustments? Collumnation, auto lock etc....
So your initial BS is good forward/reverse? You've verified that everything is plumb. The only time I've seen this is actually this time of year. Have you noted temperature changes, cloudy or sunny etc etc?
Are you setting up on concrete or directly on the ground?
I've struggled over the years with fluctuating temps this time of year. For example:
Setup 7:00 AM, temp. 28 deg.
7:30 AM, temp. 31-32 and full Sun
The gun starts to drift due to the thaw.
Stamp the legs in noticeably deeper, Re-level and by the time we can get out for a BS it's drifting again.
I've even packed snow around the bottom of the legs at times and it's worked. You mentioned Keystone Precision so I'm guessing PA. The freeze and thaw this time of year can be a real obstacle at times.
I've had guys pour me a pad on construction sights for this reason in the winter.
Initial backsite on this particular control always checks under 0.005. I'll then even go as far as to stakeout the same point and note my errors. (usually something like N:0.003 W: 0.002. As far as the leveling goes joabmc, I was having that problem a few weeks ago. I'd set up on the ridge and by the time I walked down it my gun would be 2 minutes out. Solved that by driving hubs in the ground and setting the legs on them. Jon- yes, I've ran all my adjustments. I had two schools of thought on the issue, one is that one of my tribrachs is going bad. The other thing I thought of and I don't know how or if this has ever happened was if the level screen on my collector is saying im level but in reality I'm not. The only reason I think this is because my helper said something along the lines of "I just checked the level screen 2 minutes ago and it was perfect and then it said it's a minute out and now it's perfect again" I honestly don't know how the compensator fully works and if this would something that's normal. I know I never noticed anything like that before.
I've had mine drift in and out this time of year. Looked at the screen and have watched it move. Head back to the gun and it's OK again. I'd venture to say that it's the weather conditions that are causing your issues. Try planks of wood under your legs if you are unable to get setup on solid ground.
We had the same problem. Upgraded to a 1" S7 with all nodal prisms. Slapped it all on low wide Crain Trimax tripods and the problem disappeared.
sounds good, thanks for the help. I'll trying everything over the next few days.
makes me wonder if it's the gun itself. I was just looking at the s7 last night
elkboarder, post: 412963, member: 12485 wrote: makes me wonder if it's the gun itself. I was just looking at the s7 last night
We solved quite a bit of the problem setting up low and a little wider. The accelerometer in the gun went crazy vibrating and drifted angles.
I'll bet dollars to donuts that the problem is the tribrach. More specifically, the instrument is not seating properly on the 3 contact points - usually because the contact points have become worn, or maybe because a speck of grit or something is on the points - and the instrument shifts ever so slightly as it is being used - under torque.
The next thing to check is the condition and adjustment of the tripod. If the legs are too loose at the head the whole works will shift in use.
thanks a lot guys, I'll be sure to check all of these things tomorrow.
This recent post on this forum may be related:
Backsight zero drift in Trimble S series total stations
Sunny and 70 here in Arkansas today!
Id guess tribrac contacts are worn and the tourqe from the robot rotating one way or another shifts the top of the tribrac ever so slightly. A 0.0001 or a 1" shift in roration will still throw you off easily .02'. See if the top wiggles or has any amount of play from the base of the tribrac? Or just try a different tribrac.
elkboarder, post: 412963, member: 12485 wrote: makes me wonder if it's the gun itself. I was just looking at the s7 last night
I have had problems with an S6, strange stuff. Most of the problems I have seen is the vertical sucks. S8 and VX, no problems. I also hate the huge 360 multi track prism.
I would suspect that the Trimble folks know there is some S6 issues out there. You are not alone.
Most of the time when I've seen what you're describing the tripod was the culprit. As was noted above, are you using a Crain Tri-Max?
Yes, we use the Crain Trimax. To try to narrow it down I am currently Set up using a much heavier set of legs by sitepro that I usually only use for the backsite. Also using a different tribrach. I'm in the middle of a layout running a resection and so far so good.
