Servers by jDrones

Steering Boat Not following the Waypoint exactly? Heading angle error too big

pixhawk
mission-planner

(David Boulanger) #41

Based on the size and weight of the boat combined with the propulsion system I don’t know if you can make it much better. You may want to try a few of the waypoint runs and slowly change the NAVL1_PERIOD from 8 to 10 then to 12,14,16 and see if this improves things. The I should probably be back up to .3 based on what I have read. I don’t use differential steering much but use ackerman steering so this is hard for me to advise. So try raising the NAVL1_PERIOD a few times and see if that helps.


(Yu Chen) #42

thanks David, I will try and update you about this then. Happy new year! :grinning:


(David Boulanger) #43

Any luck? just wondering. Happy New Year!


(Yu Chen) #44

Hi David,

My laptop got wet during the experiment due to the rain on that day. But after it takes a few days, just got it work!

I tried to tune the NAVL1_PERIOD=14 and it seems the performance is the best. However, when I try to increase the I slowly(from 0 to 0.1 to 0.3 etc), the performance get worse. So I just adjust it back to 0 agian. Here attached the performance: where the NAVL1_PERIOD=14, and steering_rate_I = 0

Here I attached the log, where you can see three rounds of running. For the first round I = 0, the second round I = 0.3, the third round, I = 0 again. We can see I = 0 has a relatively good performance. Do you think so?


(David Boulanger) #45

I think I would put the I at .3. NAVL1_PERIOD at 14 is probably a good number. You may want to now adjust NAVL1_DAMPING. I think it defaults at .75. Try .8 or .7. Your Des yaw and yaw are getting better.

However your desired turn rate vs actual turn rates still looks ugly on a graph.


Due to how slow your boat turns I would try changing the following parameters and see how it goes.
PIVOT_TURN_RATE 12
ACRO_TURN_RATE 10
The reason I think this is when your boat makes a pivot turn it never rotates more than 12 degrees or so a second.