AMC-AASD15A servo controller

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Finally you added it ! Bravo !
Any chance to have it on the AMC1280 ??

It could be added on the AMC1280USB easy, as its not motor control related, but more input filter on the actual received data from the PC. But I need to take care of some initial values issue first, that cause the filter to overflow (and the motors to jerk monetarily).

Thanks
Thanos

A member of my Discord made for me a cool e-stop button box that uses telephone cable with rj12 connectors and I gave it a go on my enclosures:





If you wonder how I mounted the RJ12 connector in the metal enclosure from PT-Actuator, see this video. I only used a dremel angle cutter and a bit of double side tape:




Thanks
Thanos

New firmware with filtering is almost done. A few minor changes and should be ready to release a stable version on it:




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Thanos

Demonstration of the new rolling average filtering system in latest firmware of the AMC-AASD15A, on Mike's 737 6DOF platform:






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Thanos

Here is a most complete video explaining all the parts of the huge 737 6DOF platform that Mike from New Mexico is building. Plus some bonus demonstration taxing and takeoff.






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Thanos

Part two of Mike's 737 6DOF, demonstrating a few things that got cut from the first part:

Mike really needs to use a coord. Channel.
Normally at least 15% pitch is needed while there is a 0,25G thrust applied.

As the ressources are not big, he can use maybe 10deg. At least something...

Derek from Oregon started making his 6DOF platform a few weeks ago, see his progress on these videos:











I think its great build to follow, and looks very promising despite being low cost DIY approach.



Thanks
Thanos

The upcoming firmware will have smoothing filter (Rolling Average and S-curve path correction), and most important of all it will have a hardware implemented Spike Filter, for y'all that can't keep the vehicle in the track and keep crashing against walls.

The filter is simply level based that can detect spikes larger than the average speed of your actuators, and will place the motors in position seek mode (slower artificial motion) for the duration of the crash, until the vehicle comes to a stop. This is quite effective on rollover situations that the crash side effects are sustained for quite long.

If you were using the Force Offline switch when you were about to crash, there is no need now, it acts like a automatic force offline switch, so you don't need to haste into reaching for the switch to turn off the motion.

Being implemented in hardware, means it will work on ALL motion software. Some motion software implement similar spike filter but it just cuts off the motion (freeze in place), while the spike filter in the AMC-AASD15A will keep the motors moving slower seeking to catch up with real time motion data when its safe again.




Thanks
Thanos

Thanos,

Could you please incorporate it on AMC1280?

For all, the ramp for kill switch, could you please apply this s curve with high magnitude

Best

I could try adding this filter on the AMC1280USB but it will probably slow down some functions which are already marginal since its also running a 6x full PID in the background. Also there is no proper park/standby/online transition sequence in the AMC1280USB, so when you start the motion, it will most likely jolt a bit until the stream stabilizes.

I need to think about it, to see how it can be added with minimal side effects...

The most acute thing is the kill switch ramp I would say. A tiny filter on the actuators could be interesting to make them completely calm but it’s not so urgent as the kill switch ramp.

> > > Fantastic > > > Fantastic > > > Fantastic > > > Fantastic ! ! !
Thank you so very very much... I don't crash into walls, being I'm a flight simulator, but do break a plane or two when pushing things past their limits doing acrobatic maneuvers... And as a bonus, this could make the simulator much more safer for my kids too ! ! !

A short demo of the new safety feature (spike filter) in action...





To explain what you see in the video, as soon the car hits the wall, the spike filter activates and slows down the actuators speed automatically, so you still have motion, even feel the off road bumps etc... it re-enters online motion data after a short period of seek motion of the motors to catch up.


Thanks
Thanos

Ok, final iteration of spike filter is done! Works as planned. It recovers instantly after crash, even if you keep driving !!




I added range parameter for the filter so you can fine tune the spike filter value if you are using low value. Try it here:

https://github.com/tronicgr/AMC-AAS...e/enc_6dof_AMC_AASD15A_v2_09_fix_filter12.zip


Here is a demo race with spike filter Enabled!! The stepper motor didn't jolt even once and it recovers instantly to online data...




See here a demo race with spike filter DISABLED...enjoy the jolts... LOL





Thanks

Thanos

Reminder that free DIY servo controller that allows connection with Simtools or FlyPT Mover motion software exists:

AMC-open-hardware-servo-controller-4DOF

Its about time to release the latest firmware update for the AMC-AASD15A servo controller. This firmware brings alot of new features and improvements that were done during the last month and countless beta version.


You can find this firmware on the usual github space:

https://github.com/tronicgr/AMC-AASD15A-Firmware/tree/master/Latest_firmware



======= enc_6dof_AMC_AASD15A_v2_09 =======

release date: 03/5/2020:

• Added "Rotation Offset" parameter that allows custom degrees backtrack of the rotating actuators during calibration so they can clear away from the limit switch it the hardstop. This can be set to any value between 1-90 degrees angle. It no effect on the linear actuators backtrack of the motor that is set by default to a little less than half rotation of the motor.
• Added Rolling Average Filter that is set to run globally and it appear in the LCD menu with the name "Filter Factor". The Filter Factor value is located under the "Pulse Freq" menu option. The motors must be parked or powered off as there is safety that does not allow modification of the filter factor value otherwise. It will not allow modification when you operate the buttons on the panel, or being on online mode. You can disable the filter entirely by selecting value "0" for the Filter Factor parameter. There are 5 levels of filtering:
• 0 No Filter
• 1 Hard Filter
• 2 Semi-Hard Filter
• 3 Semi-Soft Filter
• 4 Soft-Filter
• 5 ...Molasses
• The jump when entering online mode was fixed. Also fixed the jump if you activated e-stop in power off mode... it will always make sure the actuators are in park before starting motion, either offline or online.
• The new firmware will allow you to turn off the LCD updates for motor position information (bars) while still allowing navigating the menu by switching ON the DIP#3.
• I added a "Hold position" option for the Force Offline switch, which will keep the actuators on standby position (50%) while the Force offline switch is activated. Otherwise if you want to manually switch between Park and Standby positions while the Force Offline switch is active, you can select the option "Park Motors".
• It has now has a fix for when using Traction Loss axis, it will calibrate the motor in park position and then will slowly move to 50% position. While changing the Filter Factor value it will also move the TL actuator to Park position and move it back after the setting.
• Added an option to optionally change the signal level of the S-ON output pin (Enable), as some servos require High level signal to be enabled (5v).
• Added spike filter that can be adjusted by three parameters: Level, Range and ON-OFF
• 1. Level: it defines the distance in data points that the input position have to exceed for the spike filter to kick in. This is absolute 16bit value 0-65535, default value 32767. If the spike filter kicks in too often, increase this value.
• 2. Range: parameter for the Spike Filter to better fine tune the stepping of the spike filter value for lower level values.
• 3. Enable or Disable the Spike Filter
• Improved the delay caused by the Rolling Average Filter and now the motion from park to standby and to online data should be considerably faster. Also added two stage positioning algorithm to move faster for large distances and slow down when near target for these artificial movements.
• Fixes the transition to online motion data if the Force-Offline switch is used, avoiding jumps or jolts in the motion.
• Fixed the position seek during spike filtering to to a range instead a point to allow catching up to real time motion data immediately after a crash.

The Rolling Average Filter will improve the vibration levels of the servomotor, by making sure it will always receive continuous pulses without jumps because of potential gaps, or non linear motion cues from the motion software, and its adding a bit of s-curve acceleration/deceleration to allow fast and accurate positioning without banging start-stop motion of the motor, that translate to hammer noises in the linear actuator. It smooths out the pulses so good that its even possible to control a closed loop stepper without sounding like a jackhammer in operation!!

The new Spike Filter works by detecting spikes in position data larger that the defined level (most likely crashes) and it will automatically activates the Force Offline mode, that places the actuators in seek position mode until all motors catch up with live motion data. So for the duration of the crash the motors will avoid doing any intense jolts and most likely the motion will come back on when the vehicle is standing still. It should work wonders in long duration crashes like when you have rollover down a bank for example...



Some related videos:

Calibration offset for rotary actuators
Spike filter demo on AMC-AASD15A
A quick race with Spike filter Enabled on AMC-AASD15A
A quick race with Spike filter Disabled on AMC-AASD15A
Tutorial: Adjusting the Spike Filter Level and Range


Of course there is updated manual as well that includes instructions for surge:
https://github.com/tronicgr/AMC-AASD15A-Firmware/blob/master/Manual-and-Datasheets/AMC-AASD15A_4DOF+TL-Simtools_manual_v2_3.pdf



Thanks
Thanos

Sounds fantastic !

Any hope the amc1280 benefits from the new experience ?

Best