Hey guys!
For the wheelie control, I spent some time testing some CHEAP options, b/c I didn't want to pay $500 on a freaking Racepak ride height sensor, which is what they use in the US.
So I thought we could use one of the distance sensors we have in the robots I build to play with my son and guess what: the thing f* works!
Of course you have to know how to use the function and configure the sensor, so that's why only a couple guys here in BR (which happens to be friends of mine
) are successfully using them, even though I have wrote an article for a performance magazine explaining (not in details) how to use the sensor.
The sensor is a SHARP infrared sensor (GP2Y0A02YK) and it's a bit tricky to calibrate its values. You have to attach it to the car in its final position, and then lift the front of the car, inch by inch, check the sensor reading and start building your calibration table for that sensor.
One thing to notice about this sensor is that it isn't a linear sensor and it's reading table might give you wrong values if the sensor is too close to the ground. My experience with this sensor tells me to fix the sensor at a distance of at least 7" from the ground and then you can start your table from there.
So when building your calibration table, the lowest height it'll have is 7". Then you lift the front until you have the sensor at 8" from the ground, you check the reading in V and add an entry of xV - X" in the table and you'll keep doing it until you feel you have a good table.
Keep in mind the max reading for this sensor is a distance of 150cm and that's not a straight reading anymore as soon as you lift the front b/c the sensor isn't pointing straight to the ground anymore. You'll be measuring the height in a straight line, but the max reach of the sensor will still be measured in an angled way.
After that, when you check the FT display it'll be showing 7" (or whatever is your first calibration value) of reading with the car at ride height.
I like to make it read 0, so I just go to the sensor offset and adjust it to 0 my reading by setting the offset type to "after conversion" and putting the inverse of my first value in the table. So if the first value is 7, my offset is -7, which will give me a reading of 0 at ride height.
I'm attaching the draft of the article published on that magazine. It's in Portuguese but you can easily throw it in google translator and get the main idea behind the words
(I know. I wrote too much
)
The Cal-look Lounge
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