This forum uses cookies
This forum makes use of cookies to store your login information if you are registered, and your last visit if you are not. Cookies are small text documents stored on your computer; the cookies set by this forum can only be used on this website and pose no security risk. Cookies on this forum also track the specific topics you have read and when you last read them. Please confirm whether you accept or reject these cookies being set.

A cookie will be stored in your browser regardless of choice to prevent you being asked this question again. You will be able to change your cookie settings at any time using the link in the footer.

  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
MPU6050 lag
#1
First off, I'd like to express my appreciation to Sean, and all involved in the pypilot/Openplotter/OpenCPN development. I've really
enjoyed the project of getting the autopilot hardware and software working together while waiting for the weather to warm up for our voyage south. It's coming together nicely, but there seems to be one issue so far.
My setup is a Raspberry Pi 3B+, BU-353 S4 USB GPS, MPU6050 on I2C, and NMEA0183 AIS through an RS-232 to USB converter from a Standard Horizon GX2200. I also have Radar coming in from the B&G 4G through a Netgear Gigabit switch. Pypilot will be steering a Tayana 37 through an Alpha Marine Systems ballscrew linear actuator with an appropriate motor controller. All Software is updated.
My problem is apparent lag between the MPU6050 and Openplotter/pypilot. I'm pushing the "Boat Level" button in Calibration at the dock in smooth water, and get the blue bar. I haven't been able to do an actual underway compass calibration yet. As I'm playing with calibration, there is a 4 - 5 second delay between moving the MPU and all axis numbers (and the ship display) changing in the calibration screen. The delay is the same with no USB or Ethernet attached. I'm using VNC local connection for a headless setup, but the delay is the same with keyboard, mouse, and HDMI video. I've tested the MPU with an Arduino Nano and have no perceptible delay in reading the raw data.
It would seem to me that this much delay would be a big problem in controlling the boat. My searches haven't come up with any
references to this issue, so any help in pointing me to solutions would be greatly appreciated.
Thanks.
  Reply
#2
(02-26-2019, 01:38 PM)Sailbus Wrote: First off, I'd like to express my appreciation to Sean, and all involved in the pypilot/Openplotter/OpenCPN development. I've really
enjoyed the project of getting the autopilot hardware and software working together while waiting for the weather to warm up for our voyage south. It's coming together nicely, but there seems to be one issue so far.
My setup is a Raspberry Pi 3B+, BU-353 S4 USB GPS, MPU6050 on I2C, and NMEA0183 AIS through an RS-232 to USB converter from a Standard Horizon GX2200. I also have Radar coming in from the B&G 4G through a Netgear Gigabit switch. Pypilot will be steering a Tayana 37 through an Alpha Marine Systems ballscrew linear actuator with an appropriate motor controller. All Software is updated.
My problem is apparent lag between the MPU6050 and Openplotter/pypilot. I'm pushing the "Boat Level" button in Calibration at the dock in smooth water, and get the blue bar. I haven't been able to do an actual underway compass calibration yet. As I'm playing with calibration, there is a 4 - 5 second delay between moving the MPU and all axis numbers (and the ship display) changing in the calibration screen. The delay is the same with no USB or Ethernet attached. I'm using VNC local connection for a headless setup, but the delay is the same with keyboard, mouse, and HDMI video. I've tested the MPU with an Arduino Nano and have no perceptible delay in reading the raw data.
It would seem to me that this much delay would be a big problem in controlling the boat. My searches haven't come up with any
references to this issue, so any help in pointing me to solutions would be greatly appreciated.
Thanks.

I guess I should have posted this in the "pypilot" forum, but when I saw the "Need help. . . ? Ask here" I thought it might be the right place . . .

My MPU9255 and MPU9250 came in and using either one of them took care of the lag.

Thanks.
  Reply


Forum Jump:


Users browsing this thread: 1 Guest(s)