Auto levelling laser levels

[Gyro]

The simplest (usual) solution is a telescopic pole support (floor to ceiling) and a pole clamping camera mount. It will set you back about £27.

[Zenith]

@ akis

I don't think you explained this very clearly.

With a laser level, you have to get the level itself level as well as getting at the right height.

If it's level in two perpendicular horizontal directions let's call them NS, EW, the beam will be on a plane that's level. N is the direction the light comes out of the level.

There are two sorts of cheap level;

The ones with a pendulum, where the pendulum sorts out the NS,EW business and you only have to worry about the height. So if you tilt them, they compensate automatically within limits, and the beam is still on a level plane. They are levels. There may be expensive ones ones with parameters you can dial in, I don't know, but it's worth checking. In fact considering this problem altogether I think you should look into sophisticated laser levelling and sighting gear before trying to build anything, unless you like building things.

The cheaper ones, like I've got, which have two spirit levels, NS, EW, and they come with a camera tripod socket and a little table tripod. You put them on the tripod and fiddle with the ball and socket until the bubbles are in the centre of the lines. They are better used on a proper camera tripod, with height adjustment, which costs a lot more than the level. I'd imagine the dearer versions come with their own purpose designed tripod and something better than spirit levels.

So if I've understood it right, you might be in a large room and due north, 20ft up and inaccessible, there are two marks on a wall a few feet apart, and you want to know if they are level.

Well you could do that in principle with the two spirit level type level. You position yourself between the two marks and tilt EW to get level in that direction and then tilt NS vertically until the beam hits one of the marks. If they are level the beam should hit both marks. You could also design an instrument with a pendulum type level or an electronic inclinometer or something, where you put the beam on both marks and it tells you the angle to the horizontal between them.

OK in a back of a fag packet sort of way, but when you think about the geometry, and the way errors could creep in generally, maybe not so great.

I've never looked into them much, but I wonder if you couldn't do this with an old school theodolite, or the new school laser equivalent anyway.

But I'd have thought that Gyro's solution of a telescopic pole support and camera mount would be better and for only £27.

[soldar]

A complex solution in search of a non-existing problem proposed by someone who is entirely missing the complexity of the issue.

A beam spinning at 90 degrees from a vertical axis defines a horizontal plane. Every point the beam hits is on the same plane.  Extremely simple and reliable.

Now the OP proposes a rotating laser beam which can move up or down as it spins. It needs to spin at least at 25 RPM to provide a stable visible line. Many thousands of times per revolution it needs to range the distance, calculate and adjust height. How would it do this? It would start spinning in a perfect cone and then progressively adjust each point up or down which would take several revolutions to settle. This would be extremely complex to do reliably, extremely expensive and very prone to error. What happens when there are objects in the way? If it is on the floor and chairs and tables are in the way?  What happens when it hits not a vertical wall but a sloped surface like a stairway? All these calculations can get tricky and would have to be repeated many thousands of times per second.

And then you need to have a system which can point the laser up or down extremely fast as it rotates. Any error in range finding will result is wrong sweep.

Really. A simple plane laser resolves this very easily, simply and cheaply.

There is no real demand for this product.

[Brumby]

And then you need to have a system which can point the laser up or down extremely fast as it rotates.

My solution to this is to have the laser doing a cylindrical raster scan, with the indicator dots only lighting up at the right time.  While this overcomes the mechanical issue with beam deflection, there are still a dozen other considerations that make this idea impractical.

There is no real demand for this product.

Agreed.

Those who might be in the target group for such a product would already have ways to achieve the result this concept could offer - but do they need it?  The suggestion of tilers shows a complete lack of understanding as to how they work.  Professionals develop reliable short cut methods to do things and don't overthink.  Things need to be simple, quick to set up and effective.  The planar levels currently available do that.

[eKretz]

Yes this is a no go, as many of us have already pointed out. It would be beyond difficult to do this. The particular usefulness of these offerings is dependent on them projecting a line all around the room that is on a plane. Making the line deflect on a spinning laser is a problem because of the cone shape - owing to the nature of the purported cone's intersection with the planar surface that is a wall - as mentioned earlier this would not form a straight line. The more the deflection the worse it gets. As far as creating some way for the beam to variably deflect, good luck with that. To maintain accuracy would require some very expensive positioning mechanisms and electronics. It would price you right out of the market compared to the current offerings and a tape measure. On top of all that, for this to even work, you'd have to have some way of orienting the device to the shape of the room. Even more added expense. Any irregularly shaped rooms or walls would be a nightmare.

[Zenith]

The point is that as mentioned by Gyro above, there's already a cheap and reliable solution. You just find some means to raise a self-levelling laser level to the height you need. This could be a purpose made telescopic device, or some platform tinkered together say by nailing bits of wood together and nailing it to a ceiling beam. Because you'd be using the level as a level, it wouldn't matter that the room was an odd shape, or that that the walls were uneven, or curved. There might be some points in shadow from the beam, so do it again with the level in a different position to catch the missing points.

No Star Trek technology to invent and cheap.

[eKretz]

Yes,  also mentioned by myself and several others previously!