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tuning_gains [2018/09/22 22:56] 73.128.99.196 created |
tuning_gains [2019/10/02 13:20] (current) 174.226.13.56 |
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- DD - derivative' - rate of rate of turn | - DD - derivative' - rate of rate of turn | ||
- PR - proportional root - square root of heading error | - PR - proportional root - square root of heading error | ||
- | - D2 - derivative^2 - rate of turn squared | + | - R - reactive gain - reverse of command delayed |
- FF - feed forward - change in heading command | - FF - feed forward - change in heading command | ||
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- | From here, adjust just these two gains seeing how the boat reacts before adding other gains. Once you are comfortable adjusting these gains consider: | + | If the boat takes too long to correct the course and spends a long time to one side of the correct heading, increase these two gains. If the motor is working too hard, and frequently crosses the correct heading, decrease these gains. |
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P - proportional gain | P - proportional gain | ||
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D - derivative gain | D - derivative gain | ||
- | This is the gyro gain, and the main driving gain of the autopilot. Most of the corrections should be as a result of this gain. Once the best value is found it can typically work in a range of conditions, however, in light air, it can be reduced (along with reducing other gains) to significantly reduce power consumption. | + | This is the gyro gain, and the main driving gain of the autopilot. Most of the corrections should be as a result of this gain. Once the best value is found it can typically work in a range of conditions, however, in light air, it can be reduced (along with reducing other gains) to significantly reduce power consumption especially if the boat is well balanced. |
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DD - derivative' gain | DD - derivative' gain | ||
- | This gain is useful to improve reaction time. It can allow for corrections sooner than they would occur from the D gain alone. To use it, gradually increase this value up to 1.5x the D gain value without changing other gains, and notice the results. | + | This gain is useful to improve reaction time. It can allow for corrections sooner than they would occur from the D gain alone. To use it, gradually increase this value up to 1.5x the D gain value without changing other gains, and compare the results. |
FF - feed forward gain | FF - feed forward gain | ||
- | This gain is only useful when making course changes. For holding heading it has no effect. Following a route can cause course changes. It can be very useful in improving the response time since a low P value is normally desirable. | + | This gain is only useful when making course changes. For holding heading it has no effect. Following a route can cause course changes. It can be very useful in improving the response time since a low P value is normally desirable, this gain is the main contributor when the course is adjusted. |
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For sailing in protected waters, steering a less straight course is a tuning error, and will only increase power consumption. | For sailing in protected waters, steering a less straight course is a tuning error, and will only increase power consumption. | ||
- | If you can tolerate less straight steering it may save power in waves. Generally you just want to keep the sails pulling, and the average course that you desire. This was always the goal with a wind vane anyway, and can save power consumption as well as wear on the motor. | + | If you can tolerate less straight steering it may save power in waves. Generally you just want to keep the sails pulling, and the average course that you desire. This was always the goal with a wind vane anyway, and can save power consumption as well as wear on the autopilot drive motor. |