Thread: Dual encoders
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Unread 14-02-2016, 17:47
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Re: Dual encoders

Quote:
Originally Posted by Caleb Sykes View Post
My team is running a tank drive setup this year, and have added an encoder onto each side. We are also using the NavX for angle measurements. We will have a variety of methods that rely on angle measurements from the NavX and distance measurements using one or both encoders.

However, I am wondering if there is really any benefit to having both encoders. If for distance we just take a raw average of both measurements, we are basically getting slightly more precision in exchange for a doubled failure rate. It seems to me that unless you are using two encoders to sense angles in place of a gyro (or some sort of fusion) there is almost no benefit to having dual encoders.

How does your team integrate dual encoders into the code? Does anyone just mount/use a single encoder?
In industry, we would actually use 3 encoders and then always select the midvalue one.

Just as we say:
- With 1 sensor, you don't know that you're wrong.
- With 2 sensors, you know you're wrong but aren't sure which is correct.
- With 3 sensors, you always know which one is wrong and which is right

(From a single-fault-tolerance perspective)
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Last edited by seg9585 : 14-02-2016 at 17:50.