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A bit of a tangent, but in mcu firmwares, higher order filters can also be implemented directly with biquad sections. More work to implement vs single pole, but very reusable. Although to be honest...
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#3: Post edited
by
Pete W
·
2020-12-16T05:09:54Z (about 4 years ago)
A bit of a tangent, but higher order filters can also be implemented with biquad sections. More work to implement vs single pole, but very reusable. Although to be honest the benefit over cascaded single-poles is marginal, so there may be other topics, like loop stability, that might be a better use of someone's time, if they are at the stage when asking the question originally posted.- The main difference betw. biquads and single-pole's is the ability to place complex poles and zeros. IMO this is not actually desirable for filtering process data from typical sensors, due to underdamped step response.
- On the other hand ability to place complex poles and zeros CAN open up more options when put to use inside a control loop, for more difficult situations. You have to kindof enjoy the math to take this route.
- A bit of a tangent, but in mcu firmwares, higher order filters can also be implemented directly with biquad sections. More work to implement vs single pole, but very reusable. Although to be honest the benefit over cascaded single-poles is marginal, so there may be other topics, like loop stability, that might be a better use of someone's time, if they are at the stage when asking the question originally posted.
- The main difference betw. biquads and single-pole's is the ability to place complex poles and zeros. IMO this is not actually desirable for filtering process data from typical sensors, due to underdamped step response.
- On the other hand ability to place complex poles and zeros CAN open up more options when put to use inside a control loop, for more difficult situations. You have to kindof enjoy the math to take this route.
#2: Post edited
by
Pete W
·
2020-12-16T04:51:00Z (about 4 years ago)
A bit of a tangent, but higher order filters can also be implemented with biquad sections. More work to implement vs single pole, but very reusable. Although to be honest the benefit over cascaded single-poles is marginal, so there may be other topics, like loop stability, that might be a better use of the OP's time.The main thing biquads let you do is create complex poles and zeros, if you want. IMO this is not actually desirable for filtering process data, due to underdamped step response. On the other hand ability to place complex poles and zeros CAN open up more options when put to use inside a control loop.You have to kindof enjoy the math to take this route.
- A bit of a tangent, but higher order filters can also be implemented with biquad sections. More work to implement vs single pole, but very reusable. Although to be honest the benefit over cascaded single-poles is marginal, so there may be other topics, like loop stability, that might be a better use of someone's time, if they are at the stage when asking the question originally posted.
- The main difference betw. biquads and single-pole's is the ability to place complex poles and zeros. IMO this is not actually desirable for filtering process data from typical sensors, due to underdamped step response.
- On the other hand ability to place complex poles and zeros CAN open up more options when put to use inside a control loop, for more difficult situations. You have to kindof enjoy the math to take this route.
#1: Initial revision
by
Pete W
·
2020-12-16T04:48:28Z (about 4 years ago)
A bit of a tangent, but higher order filters can also be implemented with biquad sections. More work to implement vs single pole, but very reusable. Although to be honest the benefit over cascaded single-poles is marginal, so there may be other topics, like loop stability, that might be a better use of the OP's time. The main thing biquads let you do is create complex poles and zeros, if you want. IMO this is not actually desirable for filtering process data, due to underdamped step response. On the other hand ability to place complex poles and zeros CAN open up more options when put to use inside a control loop. You have to kindof enjoy the math to take this route.