Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: blake987123 on September 29, 2009, 05:18:53 PM

Title: Detecting Whether Robot is Level
Post by: blake987123 on September 29, 2009, 05:18:53 PM

I plan on building a hexapod in which the chassis is always level. My plan is to let it adjust the legs to make the chassis perfectly level. I had some ideas, but after research I don't think any of them would work. Please, does anyone have any ideas for sensors?

Title: Re: Detecting Whether Robot is Level
Post by: Razor Concepts on September 29, 2009, 06:00:38 PM

Accelerometer. Dimension engineering has a 3-axis one, sparkfun has a bunch also.

Title: Re: Detecting Whether Robot is Level
Post by: Joker94 on September 29, 2009, 06:02:06 PM

tMy suggestion on is an acelerometer. And if yopu want to keep it level you will most likly need a 3 axis one.

Some thing like this would br good as it is small and not over kill for what you need.

http://www.dimensionengineering.com/DE-ACCM3D2.htm (http://www.dimensionengineering.com/DE-ACCM3D2.htm)

Title: Re: Detecting Whether Robot is Level
Post by: blake987123 on September 29, 2009, 06:27:18 PM

Just wondering, why would i need the z axis on an accelerometer for this application?

Title: Re: Detecting Whether Robot is Level
Post by: billhowl on September 29, 2009, 06:30:00 PM

Accelerometer are expensive, This "poor man's" accelerometer! Tilt sensors are switches that can detect basic motion/orientation and only cost USD $2.

(http://www.ladyada.net/images/sensors/tiltcutaway_t.jpg)
Cutaway of rolling-ball type tilt sensor

The metal tube has a little metal ball that rolls around in it, when its tilted upright, the ball rolls onto the contacts sticking out of end and shorts them together. While not as precise or flexible as a full accelerometer, tilt switches can detect motion or orientation simply. Another benefit to them is that the big ones can switch power on their own. Accelerometers, on the other hand, output digital or analog voltage that must then be analyzed with extra circuitry.

http://en.wikipedia.org/wiki/Tilt_sensor (http://en.wikipedia.org/wiki/Tilt_sensor)
http://www.ladyada.net/learn/sensors/tilt.html (http://www.ladyada.net/learn/sensors/tilt.html)
http://www.adafruit.com/index.php?main_page=product_info&cPath=35&products_id=173 (http://www.adafruit.com/index.php?main_page=product_info&cPath=35&products_id=173)

Title: Re: Detecting Whether Robot is Level
Post by: blake987123 on September 29, 2009, 06:41:40 PM

Thanks for all your ideas, but I think I'm going with the accelerometer. I don't think tilt sensors are accurate enough for my prjoect.

Title: Re: Detecting Whether Robot is Level
Post by: Joker94 on September 29, 2009, 07:59:41 PM

i think that is a good idea as you can use the accelerometer on any project you want so it is a good investment in the long run.