Yaw rate Sensor

[bhattu13]

Hi, I am interested in using Yaw rate sensor in the Formula student car. But I am not sure about the range and sensitivity that is required of the sensor.

I could find single axis sensors for 2.5$ with 300 deg/sec range. Or even higher range but more expensive.

Any ideas or suggestions!!!

Thanks

[bhattu13]

Hi, I am interested in using Yaw rate sensor in the Formula student car. But I am not sure about the range and sensitivity that is required of the sensor.

I could find single axis sensors for 2.5$ with 300 deg/sec range. Or even higher range but more expensive.

Any ideas or suggestions!!!

Thanks

[PBnG]

300 deg/s should be plenty of range. A skidpad yaw rate is in the ballpark of 100 deg/s. Things to look out for are sensitivity to vibration in the reading and maximums above which can cause permanent damage to the sensor.

[bhattu13]

Thanks for the reply.

The peak values are usually specified as a few hundred g's for a few milliseconds. That will not be a problem I am sure.

As for sensitivity to vibration - there were noise density factors given in units '?/s/rtHz' (typical values I found 0.05). Is it enough?

Is there a way to compare the accelerometers - The only difference I can tell is the range and price!!!

[bhattu13]

I mean based on performance...

thanks again

[flavorPacket]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by PBnG:
300 deg/s should be plenty of range. A skidpad yaw rate is in the ballpark of 100 deg/s. </div></BLOCKQUOTE>

Hmm...

360/5=72. If you run a 3.6s skidpad, I must meet you and shake your hand.

[HenningO]

He did say "ballpark", and in my world being within 30% is still in the ballpark http://fsae.com/groupee_common/emoticons/icon_smile.gif

[flavorPacket]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by HenningO:
He did say "ballpark", and in my world being within 30% is still in the ballpark http://fsae.com/groupee_common/emoticons/icon_smile.gif </div></BLOCKQUOTE>

If you design around +/-30%, more power to you.

[PBnG]

How many deg/s is a spinout? How about a hairpin? A sweeper even? How do range and sensitivity affect the precision and usability of your data? Sensors are usually not designed specifically for a single, steady-state event. However a ballpark number to give someone a rough approximation of a yaw rate in a steady-state dynamic event is just that. Even in that "steady-state" skidpad you will see yaw oscillation and peaks probably close to the borders of the "ballpark." Most of us are engineers, I'm not going to do your math for you.

[HenningO]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by flavorPacket:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by HenningO:
He did say "ballpark", and in my world being within 30% is still in the ballpark http://fsae.com/groupee_common/emoticons/icon_smile.gif </div></BLOCKQUOTE>

If you design around +/-30%, more power to you. </div></BLOCKQUOTE>

I don't design in the ballpark, I do it at the office! http://fsae.com/groupee_common/emoticons/icon_smile.gif

[Garlic]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by flavorPacket:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by PBnG:
300 deg/s should be plenty of range. A skidpad yaw rate is in the ballpark of 100 deg/s. </div></BLOCKQUOTE>

Hmm...

360/5=72. If you run a 3.6s skidpad, I must meet you and shake your hand. </div></BLOCKQUOTE>

You need a big range, because of noise. I can easily see 30% noise (maybe not seen unless logging very quickly, or sometimes filtered by the sensor internally, so you never see it).

If your noise is out of range of the sensor, it will be clipped, and then the average taken and incorrect values returned.

[flavorPacket]

Oh I agree. We see 100+ deg/s in slaloms/drifting all the time. Our sensors read much higher than that.