Remora - ethernet NVEM / EC300 / EC500 cnc board
11 Mar 2023 22:13 - 11 Mar 2023 22:15 #266436
by scotta
Replied by scotta on topic Remora - ethernet NVEM / EC300 / EC500 cnc board
Took some digging, but finally found it.
# load the real-time components
loadrt remora-eth
loadrt estop_latch
loadrt and2
# estop and comms enable and feedback
net nvem-estop <= estop-latch.0.fault-in <= remora.input.4
net user-enable-in <= and2.0.out => iocontrol.0.emc-enable-in
net remora-status <= remora.status => and2.0.in0
net estop-status <= estop-latch.0.ok-out => and2.0.in1
net user-enable-out <= iocontrol.0.user-enable-out => remora.enable
net user-enable-out => estop-latch.0.ok-in
net user-request-enable <= iocontrol.0.user-request-enable => remora.reset
net user-request-enable => estop-latch.0.reset
# add the remora and motion functions to threads
addf remora.read servo-thread
addf estop-latch.0 servo-thread
addf and2.0 servo-thread
addf motion-command-handler servo-thread
addf motion-controller servo-thread
addf remora.update-freq servo-thread
addf remora.write servo-thread
Last edit: 11 Mar 2023 22:15 by scotta.
Please Log in or Create an account to join the conversation.
- frayja2002
- Offline
- Premium Member
-
Less
More
- Posts: 151
- Thank you received: 11
14 Mar 2023 03:04 #266629
by frayja2002
Replied by frayja2002 on topic Remora - ethernet NVEM / EC300 / EC500 cnc board
Hi there
Thanks for that. I managed to get it working. I have attached what I ended up with in case it is useful to someone else.
I do have another question though. I am using a STM32 based NVEM controller on a small 2040 style mill. This is using NEMA 17 motors.
When I jog any of the axis (around 100mm) the axis stops short (about .04 of a mm) and then gradually moves to the commanded position. Just by counting this can take up to 2 sec. for the axis to stop moving.
Is this expected behavior & how do I go about diagnosing this?
Thanks
Alex.
Thanks for that. I managed to get it working. I have attached what I ended up with in case it is useful to someone else.
I do have another question though. I am using a STM32 based NVEM controller on a small 2040 style mill. This is using NEMA 17 motors.
When I jog any of the axis (around 100mm) the axis stops short (about .04 of a mm) and then gradually moves to the commanded position. Just by counting this can take up to 2 sec. for the axis to stop moving.
Is this expected behavior & how do I go about diagnosing this?
Thanks
Alex.
Please Log in or Create an account to join the conversation.
14 Mar 2023 03:13 #266630
by scotta
Replied by scotta on topic Remora - ethernet NVEM / EC300 / EC500 cnc board
There is a deadband in the control loop which by default is deadband = 1 / data->pos_scale. This can be overwritten by a command line setting.
0.04mm must be very close to 1 step, so the control loop is trying to get it as close as possible.
0.04mm must be very close to 1 step, so the control loop is trying to get it as close as possible.
Please Log in or Create an account to join the conversation.
14 Mar 2023 04:22 #266631
by cakeslob
Replied by cakeslob on topic Remora - ethernet NVEM / EC300 / EC500 cnc board
I have been wondering why more people havent asked about that. I figured they had higher step scales so it went unnoticed. It took me a while to figure out what was going on. I only found reference to it in a couple config files. This config has a deadband example
github.com/scottalford75/Remora/tree/mai...s/remora-closed-loop
1 / data->pos_scale, I dont know the math on that but it seems high because the default gives me unacceptable results. When I set deadband to something like .005mm, or half of 1 step it eliminates the issue.
github.com/cakeslob/upload_things/issues/1
I havent used deadband setting with openloop steppers before, what is the benefit of a higher deadband setting?
github.com/scottalford75/Remora/tree/mai...s/remora-closed-loop
1 / data->pos_scale, I dont know the math on that but it seems high because the default gives me unacceptable results. When I set deadband to something like .005mm, or half of 1 step it eliminates the issue.
github.com/cakeslob/upload_things/issues/1
I havent used deadband setting with openloop steppers before, what is the benefit of a higher deadband setting?
Please Log in or Create an account to join the conversation.
14 Mar 2023 05:05 #266632
by scotta
Replied by scotta on topic Remora - ethernet NVEM / EC300 / EC500 cnc board
1 / data->pos_scale should give a deadband of exactly one step
eg, from my 3D printer config. SCALE = 160 (steps/mm) giving a deadband of 0.00625mm
If the deadband is smaller than one step then the loop will hunt as it can never physically achieve the commanded position. This was an issue I ran into with the earlier versions of the Remora component.
eg, from my 3D printer config. SCALE = 160 (steps/mm) giving a deadband of 0.00625mm
If the deadband is smaller than one step then the loop will hunt as it can never physically achieve the commanded position. This was an issue I ran into with the earlier versions of the Remora component.
Please Log in or Create an account to join the conversation.
- frayja2002
- Offline
- Premium Member
-
Less
More
- Posts: 151
- Thank you received: 11
14 Mar 2023 10:56 #266649
by frayja2002
Replied by frayja2002 on topic Remora - ethernet NVEM / EC300 / EC500 cnc board
So how would you apply this with a stepper system that doesn't have any feed back?
Thanks
Alex
Thanks
Alex
Please Log in or Create an account to join the conversation.
14 Mar 2023 20:32 #266699
by scotta
Replied by scotta on topic Remora - ethernet NVEM / EC300 / EC500 cnc board
LinuxCNC actually does this with steppers, both the standard stepgen component and the Remora firmware close the loop by feeding back the number of steps outputted. Of course this cannot take into account any physical lost steps.
This is the difference between LinuxCNC and other software like Marlin or Klipper and is why you can get following errors with steppers with LinuxCNC.
This is the difference between LinuxCNC and other software like Marlin or Klipper and is why you can get following errors with steppers with LinuxCNC.
Please Log in or Create an account to join the conversation.
- frayja2002
- Offline
- Premium Member
-
Less
More
- Posts: 151
- Thank you received: 11
14 Mar 2023 20:46 #266700
by frayja2002
Replied by frayja2002 on topic Remora - ethernet NVEM / EC300 / EC500 cnc board
Sorry, you are talking at to much of a high level for me.
How do I put this
1 / data->pos_scale
into my ini file to adjust it.
Should it actually be in the hal file?
Thanks
How do I put this
1 / data->pos_scale
into my ini file to adjust it.
Should it actually be in the hal file?
Thanks
Please Log in or Create an account to join the conversation.
14 Mar 2023 20:48 #266701
by scotta
Replied by scotta on topic Remora - ethernet NVEM / EC300 / EC500 cnc board
No need to do anything. It's already how the Remora component code is unless overridden by setting a value on the deadband pin.
Please Log in or Create an account to join the conversation.
14 Mar 2023 23:44 #266715
by cakeslob
Replied by cakeslob on topic Remora - ethernet NVEM / EC300 / EC500 cnc board
frayja, you would add these lines to each joint in the INI file and and the hal file
github.com/scottalford75/Remora/blob/mai...-loop/remora.hal#L50
github.com/scottalford75/Remora/blob/mai...-loop/remora.ini#L96
github.com/scottalford75/Remora/blob/mai...-loop/remora.hal#L50
github.com/scottalford75/Remora/blob/mai...-loop/remora.ini#L96
Please Log in or Create an account to join the conversation.
Time to create page: 0.218 seconds