AMC-AASD15A servo controller

Hi Mike,

Here, I'll add some photos and video for you...

Thank you for the clarification on adding Photo files directly from my computer.

Hahaha, I guessed these were the ones you wanted to show...

Yes... Some of them to give folks an idea of what my 6dof Motion Platform looks like. Thanos posted them for me to help get me started on the Forum.
Mike

I remember watching videos of you building/testing this 6DOF platform many years ago. To a engineer, a thing of beauty . Have to admire the old tech TIC.

The cockpit is a work of art!

It is... wait for the cabin to go on top of the platform...

I just made available new firmware for AMC-AASD15A. It incorporates soft transition to online mode, to avoid jumps when the vehicle is placed uphill or near the curb on the starting line...

This works best if its used in combination with the Force Office switch, to allow motion data after you started the game.


Its still beta as I'm still adding a few more things in there before release stable v2.08.

https://github.com/tronicgr/AMC-AAS...re/enc_6dof_AMC_AASD15A_v2_08_soft_start2.zip

See a quick video of testing it on my bench here:

Hi Thanos,

I am planing on building new race simulator using your board. I would like to use one motor for traction loss.
But it would be directly attached to a wheel. So the calibration of AASD-15A 80ST motor is always to the end stops?
I mean that if I don't have end stops for the motor the calibration will not be successful?

-Hartsa90

You can add external limit switch to manually calibrate the home position of the motor, if you are not using linear actuator that has physical limits.

Thanks
Thanos

Added a small change in this beta firmware to automatically Park the actuators while the Force Offline switch is active. This way it won't try to go to middle position first before parking.

https://github.com/tronicgr/AMC-AAS...re/enc_6dof_AMC_AASD15A_v2_08_soft_start2.zip

Using a switch on the Force Offline input of the AMC-AASD15A servo controller, you can keep the actuators parked until you enter the race or runway, and release the force offline when you are positioned. The actuators will then presume the actual positions from the motion cues of the game, avoiding jolts or jumps if any difference between real and standby initial values that Simtools or FlyPT are sending to the AMC controller as soon serial connection is established.

Try it and let me know please!!





Thanks
Thanos

So if I add the limit switch servo can still be used more than just one revolution.
Or does the switch limit the movement to one rev. Sorry for bothering, just want to be sure...

Thank in advance
Hartsa

Normally you would need a gearbox attached on the servomotor right? You can place the limit switch on the arm travel path of the output of the gearbox. So the motor itself will perform multiple turns, especially if you use large ration like 50:1 or 80:1.

Check the 6DOF platform here with rotary actuators. It actually not even using limit switches, just a hard stop in the path of the arm of the actuator:

Ok, first tests of this new beta firmware with soft start using Force Offline switch are encouraging. The results on actual platform are better than expected.





So why use e-stop that disables the servo drives and drops the actuators free fall, when you can just safely park them instead until you need motion on your rig again? Using the Force Offline switch, the communication is not disconnected, the controller still receives the motion cues, just chooses to ignore them. This is particularly useful if you are in the middle of the race and wanted to suspend motion for a part of the track that is more rough than anticipated or you need a quick temporary break from motion...


Thanks
Thanos

Hi Thanos,
I was wondering if it would be easy for you to implement torque mode with these drives and your control. I am thinking about a seatbelt tensioner and instead of position mode and springs or something, would rather use torque mode. I have other projects planned later too which I would rather use torque mode on.

Would be a nice addition to the already pain free control you have made.

Hmm, I think that the only thing needed would be to set the servo drive in Torque mode, and use external limit switch for calibration of home (zero torque). The same pulse commands that are used for positioning should be able to be used for torque as well... I'll investigate as soon as I get some spare time.

Thanks
Thanos

The torque mode in the AASD-15A doesn't use pulses like in the positioning mode. It accepts an analog voltage (controlling the torque) on a different input, so wiring is different. You don't need a special controller for that, any arduino with a DAC can do it or you can use a pwm output as DAC. I use arduino due (because it has a 12-bit DAC) for my seat belt tensioner. Just send the value via usb to the arduino and set the output value, there are a lot of sketches available that do just this.

True, I just checked the manual, the torque mode is controlled by analog signal...

However, you can set small travel positioning mode on the motor, like 10mm and have the motor torque by adjusting the distance from 0-10mm position, the torque will be proportional to the commanded position... You can torque the motor up to 300% before it gives error alarm.

Thanks
Thanos

Appreciated. But when I have a 7dof controller only using 4dof already connected to my pc, everything else automatically becomes a special controller. You know what I mean?
On top of that, the arduino due DAC only output 0.55 V to 2.75 V. So you need extra hardware to get that to -10v to +10v. Granted you only need torque in one direction for a belt tensioner so thats 0-10v but still special crap involved and I want full torque in both directions for projects in the future.

Seems like it wont work if I move the actuator. That's the whole point of torque mode. Anywhere the actuator is positioned, it gives x torque. If I want to make a helmet mover with torque mode and I move my head away from the position commanded, the torque will grow the further away my head moves. No good.

Is there no way to add toque mode with your control Thanos? You have access to the pins for analog signal...
Could be another selling point.