GPS location on excavators

[JimBruce42]

I'm not really sure if this should be in the excavator or GPS section, so I'll start it here, and if it's wrong, someone will move it.


My question is about the placement of the GPS receivers on excavators. We use Trimble dual mast GPS and have it on all of our Mass Ex. and a couple of the pipe 345's as well. Currently they are located on the counterweights, where everyone used to put them, and because of how high and close to the edge they are, our safety department is now requiring that we put handrails around the entire upper deck. I think hoeman or pullpan posted a shot of the "prototype version".:usa Well anyway I had a safety thing last week and this came up, and I mentioned that I've seen photos of them place towards the front of the engine compartment so you don't have to climb up on the hood. To me this would be safer and you wouldn't have to worry about removing and assembling the handrails every time the machine had to move, so I asked why not just do that. The answer was that the boom will tend to interfere with the signal too much, which I get, but I wondered if anyone has run a hoe with the GPS in this new location and if they have found much difference in signal strength or reliability?


photo#1: GPS on counterweight
photo#2: on the front of the engine hood... sourced from Cat.com (Sorry, I know i've seen clearer shots than this, but this is the best photo I could find of it tonight:Banghead )

 

[Turbo21835]

I wouldnt think it would make that big of a difference. Now my question is, why cant the have a similar set up on graders. Lets get rid of those poles on the blade and have position sensors like on an excavator.

 

[cregadkins]

The original Cat placement was on the counterweight like your machine is. Cat chose to move them forward for safety reasons. I have modified two 345C's, moved the GPS receivers forward to the position in front of the hood. It has made no difference in reliability and has not caused any loss of signal. Both of these were done over a year ago. If you change the position of the receivers, you will have to re-do the GPS calibration. Also, we had to do some modifications to stiffen the tinwork that the receiver masts were mounted to. Not a real big deal to change and it is a much safer design.

 

[stock]

Something like this???


Stock

 

[JimBruce42]

The original Cat placement was on the counterweight like your machine is. Cat chose to move them forward for safety reasons. I have modified two 345C's, moved the GPS receivers forward to the position in front of the hood. It has made no difference in reliability and has not caused any loss of signal. Both of these were done over a year ago. If you change the position of the receivers, you will have to re-do the GPS calibration. Also, we had to do some modifications to stiffen the tinwork that the receiver masts were mounted to. Not a real big deal to change and it is a much safer design.

Yeah, that is kind of what I figured. The GPS guy tried to tell us that triangulating the receivers to the bucket position was easier or more accurate at the counterweight than the front. I didn't see it, but geometry was not my best math. As far as re-calibrating them, they will have to anyway, because they are going from the 18" masts to the 4' masts, to compensate for the handrails. I was surprised to say the least, that he hadn't even heard of the adjusted location, our mechanics, technicians, and safety personnel are usually on top of things 110%:beatsme

Do you have any photos of your 345c's:drinkup?

 

[cregadkins]

I do not have any pictures of the two I did, but here is a shot from a Cat Specalog.

 

[cregadkins]

Here is a picture from the rear also. We fabricated some steel plates with the bolt holes for the masts and welded them underneath the covers. Have to cut a couple holes for the harness to pass through and re-route the harness to this location. Both of my customers are very satisfied with the results and it makes it a lot safer to install and remove the receivers.

 

[Iron Horse]

3 questions , 1 , would they not be more accurate on the centerline of the turntable so that if the machine has it's tail in the air the effect would be less ? 2 , As handrails are only required above a height of 1.8 metres or 6 feet . And if the recievers could be reached by slewing the machine 90* and then standing on the tracks , would that not be suitable ? Or would that make too much sense ? 3 , Why are'nt the utillity providers made to plot all the underground services so that machines with GPS could dig up close and know where they all are instead of the hit and miss and inconvienient Dial Before You Dig ?

 

[JimBruce42]

Thanks cregadkins... those are just the pictures I wanted to see.... I wonder if we'll ever switch to that way. I imagine the 345d's are probably factory ready with hard points already in place.


Iron Horse,

When the receivers are in the location of those last photos you can get to them as easy as checking the oil (same platform), I don't think it would be feasible to try to swing around 90 degrees to try to take them off... it's higher than it looks. As far as putting them over the turntable, there really is no point, cause they are giving real time position of their location, there are sensors on the boom, stick and bucket linkage that measure the movement and then the computer in the cab takes those measurements to give an accurate location of the bucket teeth in reference to the receivers. In more basic terms, its making a triangle, the two bottom points are the receivers and the top point is the bucket. I Hope that makes sense, it's kinda technical:bash:Banghead

As for the utilities... the utility companies are the ones responsible for marking the lines "before you dig"... somehow I doubt they would be a lot more accurate if they had to plot them with GPS.:drinkup

 

[Iron Horse]

Iron Horse,

When the receivers are in the location of those last photos you can get to them as easy as checking the oil (same platform), I don't think it would be feasible to try to swing around 90 degrees to try to take them off...

Our economic vandals over here want hand rails around the perimitter for the reason it is higher than 6' and BECAUSE you are up there checking the oil .

I thought if they were servicable while standing on the tracks and the oil could be checked with a lengthened , repositioned dipstick it would foil them .

 

[cregadkins]

Glad to help you JimBruce42. I wish I had found this forum a long time ago. Good stuff!
Yes, the 345D comes with mast mounts in this location if you order it with the "AccuGrade Ready" Option. Looks like you answered all of Iron Horse's questions so I will leave those alone. Oddly enough, we are starting to hear about utility companies making GPS map locations of their infrastructure. Probably will take a long time to get it done, though.

 

[hoeman600]

Jim you forgot what we are doing

 

[Turbo21835]

Alright, i see the wise safety solution for the excavator receivers. What are the wise safety mans solution for the dozer blade receivers?

 

[cregadkins]

Alright, i see the wise safety solution for the excavator receivers. What are the wise safety mans solution for the dozer blade receivers?

Here is a solution that a Cat Dealer in Denmark came up with.

 

[grunk36]

Here is a solution that a Cat Dealer in Denmark came up with.

hey i think that dozer is mine:cool2

 

[cregadkins]

Small world!

 

[JimBruce42]

Jim you forgot what we are doing

I eluded to it, but yeah I didn't really go into detail. I asked Corey last week about the alternate option which creg posted, because if it's for safety then why not move them off the counterweight all together right? Too late I guess, they had the handrails in the paint shop already, so I guess you'll be getting yours soon too:drinkup

Alright, i see the wise safety solution for the excavator receivers. What are the wise safety mans solution for the dozer blade receivers?

In our case, we have the little foot platform, from what I hear we're getting a handrail welded to the pole as well, and that's it.... for now.

 

[AtlasRob]

In our case, we have the little foot platform, from what I hear we're getting a handrail welded to the pole as well, and that's it.... for now.

Couldn't you get a fixing lug welded 3/4 way up the mast then if you had a full safety harness on, you could clip onto the lug and safely fit or remove the senders without fear of falling :Banghead

Bloody safety morons do my head in at times.

Has anybody done a risk assessment and working plan on how to remove those handrails and refit them again each time you need to move the machine or is that another can of worms nobody has got around to opening yet :drinkup

 

[hoeman600]

funny thing is the dishes were much lower but with the rails they had to raise them any way cuz they blocked the signal:Banghead. this is mine but the rails are on the way ive heard. dont matter the hoes just sittin anyway. I have not run it iin a month. only 1 of 4 is working rite now.

 

[JimBruce42]

Couldn't you get a fixing lug welded 3/4 way up the mast then if you had a full safety harness on, you could clip onto the lug and safely fit or remove the senders without fear of falling :Banghead

SHHHHH!! Don't say that, you'll doom us all. LOL:Banghead:drinkup Seriously though, our pipe laborers are gonna have to tie off to enter or exit a trenchbox 12 feet or deep. Even had a custom made pole that attaches to the side of the box for them and everything.

Bloody safety morons do my head in at times.

Has anybody done a risk assessment and working plan on how to remove those handrails and refit them again each time you need to move the machine or is that another can of worms nobody has got around to opening yet :drinkup

From what I heard, and hoeman can confirm or deny this, they will have to be removed before transport each time. That is why I would think moving the recievers to the front of the engine cover would make things a lot safer AND less of a headache. Then if you still want hand rails you could probably have them flush with the top of the cab and they wouldn't have to come off at all. But hey, I'm just a yellow hat what do I know:beatsme:usaointhead