Hi. I have shaking on all 3 axis when i turn on stabilise mode. Can you help, cant find out where the problem? Firmware 1.03. Gain settings pan/roll/tilt = 70/70/70 Thx!
Hi Aerolab, yeah, please repost that video. All we see is a rectangle with "This video does not exist." Also it would be very helpful to understand your configuration, so could tell me the following: 1. Can you tell me exactly how you have the Radian sensors connected? Please identify each sensor and the connections to each port on each sensor. For example: Roll Sensor: Port 1. GR-24 receiver and power. 2. 3. To Tilt sensor 4. To Roll Servo 2. Than could you follow this procedure please: a. With the gimbal powered off, connect up the USB and adapter from your PC to the Radian sensor to which you have the receiver connected. b. Power on the gimbal and sensors with the transmitter set to the Off mode for the Radian sensors. c. Use the Radian software, connect the Radian cable to the Radian sensor connected to your receiver. d. Click on the Connect button to connect to the Radian sensor, and check you have a connection. e. Click on the Read button. f. Take a screen shot of the Diagnostic and Configuration windows and post it to this thread with your response to Question 1 above. g. Then connect up to the other two Radian sensors in turn, do a Read, and take a screen shot of the Diagnostic Window and Configuration Window and post those screen shots too. Thanks Andy.
aerolab, your gains seem quite low : the cause of shaking in these situations is usually that the gimbal is mounted too soft to the airframe. When the Radian tries to move the axis, the rest of the mount moves in the opposite direction and the Radian ends up in an oscillation against the damping. It's all a question of tuning to get acceptable results. A higher vibration airframe might need software mounting and hence it is easier for the Radian to oscillate. Tighter damping means less chance of that - but vibration may get through.
Good point, John. @Aerolab: If this solves your problem, no need to go to all the trouble of uploading details of your configuration, of course. Andy.
John, could you please clarify this a bit? I've been chasing a vibration issue unsuccessfully for weeks. Every 10 seconds or so I get a shudder, even with no payload, and radians off. I've changed props, gains(currently at roll 135, tilt 110, pan 70) a motor, and am now going through the systematic swap-a-motor drill to eliminate this vibration that the radians can't seem to compensate for. I use all orange rings. How can I employ software mounting to help me out? What is software mounting anyway? Thanks much -m
LOL Mike - it's just me showing my geekiness. I meant softer, not software I've noticed that if a motor shaft is slightly bent, it can seem OK at lower RPMs but cause a big vibration when you punch in some power. Hopefully your motor swap will find this - bit it's a real pain finding the culprit huh ?.
Geek is indeed good. I know. I is one. So's Mike, I believe. The real problem is that JohnC and I have "finger macros" developed over the years, so when we need to type "soft" it automagically transforms into "software." Andy.
By the way, Mike, if you have a moment, could you check this thread. Of special note is message #27 on page 2 which has some sample FPV video -- is this the kind of vibration issue that you're seeing -- from your description it is, and thus I'm having what I think is a very similar problem to yours. I've not had time to resolve it because I'm working on a DVD, A Rather Good Guide™ to MK Tool and MK_GPXTOOL. But I'm keenly interested to know what you find. Andy.
Hi Andy. Sorry for the delayed response here. I've been "distracted" for a few days. Indeed, my vibration is similar, albeit less pronounced, and at longer but regular intervals. I'm very interested in following your efforts here. I'm expecting 2 new motors this week to replace some suspicious characters I'm running now. I will strap on a gopro to boom1 and fly a dead weight 760V to compare. I loved your Rather Good Guide to the CSx build and look forward to this production. I've been intrigued by the concept of waypoint flying, but was disappointed by the initial results I saw from Jeff. Of course Holger makes it look better and easier than sliced bread. I'll update you after the motor swaps. I tend to agree that it's some type of airframe resonance that is accumulated and compensated for, but who knows. Thanks for all you do here Andy. -m
Yeah. I know the feeling. "Work" happens! One of my baseless hunches is that, with the changing speeds of the motors, it's possible to set up a beat frequency that has a subharmonic that induces the gimbal to vibrate at its natural frequency. Because of the forces and/or constraints on the gimbal (more downward, less horizontal) it tends to vibrate laterally rather than vertically. So every so often (at least on my RTF C8, the gimbal gives this pronounced rotational waggle for a second or two, and then stops, pauses, and then does it again. Using MK_GPXTOOL, which allows you to synchronize FPV video with GPX data, I'm hoping to see if I can correlate anything in the motor current draw etc. with the waggling. My current plan, when the weather improves and I have finished the MK Tool DVD, is to to fly a "dummy camera" which is an instrumentation recorder with a 3-Axis accelerometer on the camera platform and a Go Pro on a boom looking at the gimbal, so I can try and capture some real-world data on what's going on. It will be several weeks before I can get to that. Please post what you find, Mike. Thanks for the compliment. I'm looking forward to finishing the next DVD too! <grin> I think I would need to build considerable confidence in WP flying before I would use it on a production shoot and, even then, my hands would be soooo close on the sticks and ready to disable the automation in a heartbeat. As others have observed, the GPS is a consumer-grade device and works well with good skyview -- remarkably well, in fact, but I hesitate to trust custody of my bird to it. My position is one of "distrust and verify!" Again, thanks! Much appreciated. Andy.