Society of Robots - Robot Forum
Mechanics and Construction => Mechanics and Construction => Topic started by: offy on March 08, 2009, 12:37:05 PM
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I am thinking about buying this
http://www.acroname.com/robotics/parts/H7-DISTANCE-SENSOR.html (http://www.acroname.com/robotics/parts/H7-DISTANCE-SENSOR.html)
or this one
http://www.robotshop.us/hitec-distance-sensor-1.html (http://www.robotshop.us/hitec-distance-sensor-1.html)
and put it facing down so my robot wont go off edges. Will this be a good choice or should I get something else?
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the second one I' watch depending on how far yu want to put it off the ground normally they have minumum measure ments where as that one doesnt have one
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Is there any other way to make it have edge detecting? What other sensors could I use? It is kinda close to the ground.
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well theres sonar... um you could take a touch sensor and build some typf cotraption so when its gliding across the surface in front of the bot it will keep the sensor pushed in and if the rider in front goes of an edge the senor will b released to have your robot know to say back up.... um yould let it fall put an accelorometer on it so when it senses its going down however fast on the z axis it will deploy the airbag or a small parachute perhaps.. Idk built something up to where its approx 12cm tall off the groun with an ir and have it extending out about 4 inches and looking down so if for say it notices that it can see farther than 14 cm(instead of 13 irs accurate but just incase ) Then have it for say if it is seeing less than 12 cm it will know theres an object in the waty so then it would turn around what not whatever you want it to do... Then you culd also have another one directly above the othe ir looking straight and watching for objects in the way... I'm sure there are other sensors out here but these are the best ones well most common....
You talk as if you already have it built if so and you can post a pic it may be easier to help you
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Sharp has a lot of IR rangefinders, I know one has a minimum distance of 3cm which you could use.
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I did not find any 3cm range finders. I have been looking but no luck.
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http://www.acroname.com/robotics/parts/R146-GP2D120.html (http://www.acroname.com/robotics/parts/R146-GP2D120.html)
My bad, looks like its 4cm
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This is my robot since you wanted to see it. Also I don't think a button will work, since when it unsets it will pop out, than it will get stuck on the edge.
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nice job on building that anyway heres the button idea I was talking about.. it actually is kind of complicated
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Ya, that is kinda advance. I am going to be searching for some touch sensors that would work better and be simple to use.
I think this would work
http://www.robotshop.us/vex-bumper-switch-2.html (http://www.robotshop.us/vex-bumper-switch-2.html)
Maybe I will just mount this and make it so if value > treshold it will just do back and turn.
http://www.robotshop.us/sharp-gp2d120-ir-range-sensor-1.html (http://www.robotshop.us/sharp-gp2d120-ir-range-sensor-1.html)
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I think a micro switch would do the job.... that way they dont cost about but like 2$ you could have several different models and see which works the best....
Yeah with the ir range finder it would be a lot easier I think you will have to add a little to raise the height and make it to were its off of your base looking down another thing to factor in is what if the edge is to the right or left and your robot is coming in at an angle and also What if Its so happens you back off and go over the edge?
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Well how do micro switch attach to my Roboduino? And if I do buy those, I will put one on front and back.
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Couldnt you just use a normal IR sensor? if youre only trying to sense whether theres anything below the robot, these are the way to go.
something like this http://www.sparkfun.com/commerce/product_info.php?products_id=246 (http://www.sparkfun.com/commerce/product_info.php?products_id=246)
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paulstreets
thats the reality.. but he bumper switch is a cool idea...
go here to read up on microswitchs http://www.societyofrobots.com/sensors_tactbumpswitch.shtml (http://www.societyofrobots.com/sensors_tactbumpswitch.shtml)
as of the roboduino I have no experience with it... I could try to tell you butit maybe wrong and sometmes in electronics wrong equals more $$$ than you thought...
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Oh, cool. I can do that and that will work great with the roboduino. I will keep that in mind, same with the range finders and bumper switches.
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Look at the MARK III robot store, they have some good edge sensors.
http://www.junun.org/MarkIII/Store.jsp (http://www.junun.org/MarkIII/Store.jsp)
more specifically this one: http://www.junun.org/MarkIII/Info.jsp?item=50 (http://www.junun.org/MarkIII/Info.jsp?item=50)