need help regarding tilt alarm

[cybertooth]

Hi . I am newbie with basic knowledge of electronics. I need advice regarding a project.
I want to build a small narrow device which can be attached to a 16mm rod moving to and fro in horizontal direction relative to a table.The device should indicate if there is any change of more than 2 degrees in the tilt of the rod relative to the table . It would be great if the angle is adustable I.e the angle between the table and the rod. What I am looking for is that an alarm goes off when the angle changes for more than 2degrees of the set parameter. I am looking for a small sensor on the rod which can be attached to the circuitry by a 1 or 2m wire.

 

[shrtrnd]

So, how critical is your application?
They've got cheap devices that will do this, and they have expensive ones for precision work.

 

[cybertooth]

The application is not very critical but it would be good to have something which can detect a 2 degree change in angle. Please suggest some such devices.

 

[shrtrnd]

I don't know who you would buy from.
What I would do in your situation is Google 'tilt switch' and start looking.
You'll find tilt switch manufacturers, Ebay, Amazon, lots of hits.
Narrow your search parameters to zero-in on the physical requirement and price range you want.
THEN identify the part number of the one that best suites your application and search for that type to buy.
My suggesting any one, would not be as effective as you looking at the types available through Google, on-line,
and making the selection you best believe fits your needs.
Good luck.

 

[cybertooth]

thanks . but i have checked out tilt switches, they do not meet my requirements. I am looking for something where the initial angle can be set and an alarm goes off if there is any deviation from that angle .

 

[(*steve*)]

Check out G sensors. You can get three axis devices that are accurate to a part of a degree.

All you need do is connect one to a microcontroller and after you have "set" the initial position it can be programmed to generate an alarm if there is a deviation beyond a certain point.

How good are you at programming?

 

[cybertooth]

Sounds promising, actually I am not into programing but can get help .
This is what I am looking for :-
I have a air driven drill which I use for carving patterns on different surfaces, the thickness and slant of the surface varies with different materials and areas, what I need to do is keep the drill always perpendicular to the surface , this becomes a bit tricky when there are multiple carvings or the surface has variable thickness in different areas. Hence I am trying to make a device with a sensor on the drill which can alert me of change in angulation of the drill. I am attaching a diagram of the set up.

 

[Alec_t]

Why not go old-school and use a circular bubble level?

 

[cybertooth]

Yes spirit level is the simplest solution for these situations but there is another situation in which it doesn't work, sorry the other picture didn't get uploaded last time . Here is the situation which is my main concern. Another thing to be noted is that the drill is not stationary , it has to move around according to the pattern at a constant depth.
Please have a look at the image below and give your suggestions.

 

[hevans1944]

Looks like a 3-axis accelerometer sensor with LED readouts for ±error indication, processed from roll, pitch, and yaw accelerometer outputs, would work. Point the drill in the right direction, press a button to store initial accelerometer values. If deviation on two axes perpendicular to the drill exceeds two degrees (or whatever you program or set) the appropriate LED lights up... or maybe all the LEDs light up initially after reset button is pushed and then one or more go out if the drill tilts outside pre-determined limits. I think that latter might be a better HMI (Human-Machine Interface) while carving panels. But you could program it to work either way, allowing the user to make the selection. Could possibly integrate everything on one circuit board that mounts to the top of the hand-held drill with a long cord taped to the air supply hose and extending to a wall-wart power supply.

Neat project! Lots of floating-point arithmetic and solid trigonometry required to resolve drill-bit tilt from any starting orientation while ignoring rotation about the drill axis, which is why you need FP trig operations. Really good description of what you are trying to DO! Thank you for that.

Can you handle the details, or do you need more help?