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Given the complexity of resolving different magnetic flux densities , the system must struggle to scale up to large layouts with many magnets as the patterns could be very difficult to resolve , then you add the effects of external magnets , other ferrous objects on the layout ( for example a TMD , which lots of locos sitting together , or an O gauge train of 6 metal carriages passing.  Hmmmm 
 

 

Edited by Junctionmad
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Just a thought he states that it can be used with Loconet and lists specific DCC systems but there is no mention of Digitrax systems which use loconet, which I will hasten to add, that digitrax control the licensing of Loconet.

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2 hours ago, Junctionmad said:

I think I end up with the baseboard wiring !! 

Best DCC practice for anything but a small layout is two wires to every piece of track, regardless of whether you are using automation or not. This is also something that Railmagic have not grasped with their claim of being able to return to just two wires to the track.

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10 hours ago, Junctionmad said:

Given the complexity of resolving different magnetic flux densities , .........
 

 

 

You're assuming it measures flux.   What follows is speculative, and could be entirely wrong...

 

Someone posted earlier/elsewhere an identification of a three-axis magnetic sensor (similar to those used in quite a lot of smartphones) in the loco-mounted detector device.   It may measure field orientation as it passes a magnet cluster, which is far easier than flux levels.    (The measured field orientation in each loco will be different due to differences in how the detector is installed, but that's OK).   

 

If the layout configuration is known (which it is, the user has to draw a track plan for the system), then I have a back-of-envelope scheme which can identify loco position with a few (around four) different magnetic field patterns.   Those can repeat around a layout because the track is known, the possible "next pattern" for a train whose current position is known is tightly restricted.   In practise, the magnetic field orientations will be subtly different each time, and the three-axis magnetic sensors are pretty sensitive to field orientation, so all fields being unique around a layout is the most likely outcome.   

 

 

10 hours ago, Andymsa said:

Just a thought he states that it can be used with Loconet and lists specific DCC systems but there is no mention of Digitrax systems which use loconet, which I will hasten to add, that digitrax control the licensing of Loconet.

 

The software drives trains and changes turnouts on the layout as part of driving trains.   If one owns one of the listed command stations, they all have graphical user interfaces showing track position.    If the RailMagic is changing turnouts (downstream) is has to communicate back up to the command station to inform it of new turnout positions, otherwise the track diagram provided by an ECoS/Z21 (etc.) will be wrong, and the user can't manually drive trains.    

 

LocoNet is one way to communicate that information back to the command station.   Yes, Digitrax own the rights to LocoNet, and provide licenses to other makers.   

 

On RailCom, which has been talked about, the preamble for a Digitrax command station is a "short" preamble, which only allows the basic short RailCom messages.   For Roco, ECoS and Digikeijs, the preamble is a "long" one, which allows the full long RailCom message.    (The other very common US system, NCE, is even more problematic for RailCom due to the preamble bits ).

 

 

 

 

As I said, all speculative.   

 

 

- Nigel

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9 hours ago, RFS said:

Best DCC practice for anything but a small layout is two wires to every piece of track, regardless of whether you are using automation or not. This is also something that Railmagic have not grasped with their claim of being able to return to just two wires to the track.

I think he doesn’t understand the hobby at all quite frankly 

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Just been looking at the manual again, currently the max current is 3amps although it does state 5 amp maybe. Also track voltage 14/20. These ratings will rule out many users. Also Märklin users must use Dcc commands, although not common here in Europe it is so those users are out if they don’t want to use dcc commands.

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33 minutes ago, Nigelcliffe said:

 

You're assuming it measures flux.   What follows is speculative, and could be entirely wrong...

 

Someone posted earlier/elsewhere an identification of a three-axis magnetic sensor (similar to those used in quite a lot of smartphones) in the loco-mounted detector device.   It may measure field orientation as it passes a magnet cluster, which is far easier than flux levels.    (The measured field orientation in each loco will be different due to differences in how the detector is installed, but that's OK).   

 

If the layout configuration is known (which it is, the user has to draw a track plan for the system), then I have a back-of-envelope scheme which can identify loco position with a few (around four) different magnetic field patterns.   Those can repeat around a layout because the track is known, the possible "next pattern" for a train whose current position is known is tightly restricted.   In practise, the magnetic field orientations will be subtly different each time, and the three-axis magnetic sensors are pretty sensitive to field orientation, so all fields being unique around a layout is the most likely outcome.   

 

 

 

The software drives trains and changes turnouts on the layout as part of driving trains.   If one owns one of the listed command stations, they all have graphical user interfaces showing track position.    If the RailMagic is changing turnouts (downstream) is has to communicate back up to the command station to inform it of new turnout positions, otherwise the track diagram provided by an ECoS/Z21 (etc.) will be wrong, and the user can't manually drive trains.    

 

LocoNet is one way to communicate that information back to the command station.   Yes, Digitrax own the rights to LocoNet, and provide licenses to other makers.   

 

On RailCom, which has been talked about, the preamble for a Digitrax command station is a "short" preamble, which only allows the basic short RailCom messages.   For Roco, ECoS and Digikeijs, the preamble is a "long" one, which allows the full long RailCom message.    (The other very common US system, NCE, is even more problematic for RailCom due to the preamble bits ).

 

 

 

 

As I said, all speculative.   

 

 

- Nigel

Surely field orientation would be modified by the presence of ferrous metals , other trains , etc. 
 

If it can measure multiple field orientations it should be capable of continuous position calculations and would not need BEMF dead reckoning 

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Hi,

 

I speculated that a tiny square black electronic device on the RailMagic tracker that was the same size as a 3 axis magnetic field detector I found in an online  electronic catalogue was the magnetic sensor for the tracker.

 

We know the tracker is connected to the motor connections of the DCC decoder.

RailMagic say info is sent back from the tracker to the RailMagic control unit.

The RailMagic control unit is interposed between the command station/booster and the track.

 

So it could be speculated that the system may be able to get pretty regular updates from each loco as to where it was when it was in range of a magnet and what speeds it has been doing.

 

If that is true then it is different from existing train automation systems that get info from a layout mounted sensor that a loco reached a waypoint and then rely on certain types of DCC decoder to repeatedly stop the loco with accuracy.

 

My club layout could do with a system that could display where locos are and what speeds they are doing as when operating from the fiddle yard at the back of the layout the backscene hides the train from view on the scenic section.

 

I'm not sure that RailMagic will offer such a feature.

 

Regards

 

Nick

 

 

 

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1 minute ago, Junctionmad said:

Surely field orientation would be modified by the presence of ferrous metals , other trains , etc. 
 

If it can measure multiple field orientations it should be capable of continuous position calculations and would not need BEMF dead reckoning 

 

The field orientation near a cluster of rare-earth magnets is not going to change significantly by other trains moving by, the rare-earth field will dominate.   (An uncoupler electromagnet in the middle of a cluster changes the field).  

The field orientation when 50cm away from the rare-earth magnets won't be very different to the earth background field.  So, much the same anywhere on a layout apart from near a magnet cluster.  

     

 

 

 

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12 minutes ago, Andymsa said:

Just been looking at the manual again, currently the max current is 3amps although it does state 5 amp maybe. Also track voltage 14/20. These ratings will rule out many users. Also Märklin users must use Dcc commands, although not common here in Europe it is so those users are out if they don’t want to use dcc commands.

We run at 8A on the O gauge single booster 

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At present Railmagic is a closed shop system. Ie you need all his software which essentially is a replacement for TrainController or iTrain. Given it will take several years to rival the features of these packages , it might have been better to design a system that could have been interfaced to these types of control solutions. 
 

given most proper DCC layouts are wired with track droppers , adding spot or section detectors is a simple addition , so the claimed advantages of Railmagic in using magnets are not going to transpire in real situations , moreover the disadvantages of adding an additional circuit board in the loco are very real and present a significant difficulty. 

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2 minutes ago, NIK said:

Hi,

 

I speculated that a tiny square black electronic device on the RailMagic tracker that was the same size as a 3 axis magnetic field detector I found in an online  electronic catalogue was the magnetic sensor for the tracker.

 

We know the tracker is connected to the motor connections of the DCC decoder.

RailMagic say info is sent back from the tracker to the RailMagic control unit.

The RailMagic control unit is interposed between the command station/booster and the track.

 

So it could be speculated that the system may be able to get pretty regular updates from each loco as to where it was when it was in range of a magnet and what speeds it has been doing.

 

If that is true then it is different from existing train automation systems that get info from a layout mounted sensor that a loco reached a waypoint and then rely on certain types of DCC decoder to repeatedly stop the loco with accuracy.

 

My club layout could do with a system that could display where locos are and what speeds they are doing as when operating from the fiddle yard at the back of the layout the backscene hides the train from view on the scenic section.

 

I'm not sure that RailMagic will offer such a feature.

 

Regards

 

Nick

 

 

 

Nick. Continuous position updating would be a game changer. But it looks like Railmagic doesn’t do this. It seems to build a pattern of the fields at a specific series of known points on the track. It then uses BEMF to essentially dead reckon from  that known point 

 

Given that’s seems to be the case. This is essentially just another spot detector system. It suffers from all the issues of spot detection ( ie block occupancy is hard to do , what about rolling stock in the section etc ) 

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5 minutes ago, NIK said:

Hi,

 

I speculated that a tiny square black electronic device on the RailMagic tracker that was the same size as a 3 axis magnetic field detector I found in an online  electronic catalogue was the magnetic sensor for the tracker.

 

We know the tracker is connected to the motor connections of the DCC decoder.

RailMagic say info is sent back from the tracker to the RailMagic control unit.

The RailMagic control unit is interposed between the command station/booster and the track.

 

So it could be speculated that the system may be able to get pretty regular updates from each loco as to where it was when it was in range of a magnet and what speeds it has been doing.

 

If that is true then it is different from existing train automation systems that get info from a layout mounted sensor that a loco reached a waypoint and then rely on certain types of DCC decoder to repeatedly stop the loco with accuracy.

 

My club layout could do with a system that could display where locos are and what speeds they are doing as when operating from the fiddle yard at the back of the layout the backscene hides the train from view on the scenic section.

 

I'm not sure that RailMagic will offer such a feature.

 

Regards

 

Nick

 

 

 


want is one thing, actual reality is another. Your basing your thoughts on how railmagic works on speculation. 

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10 hours ago, Grovenor said:

I don't see any relevance to loconet as the railmagic stuff is all downstream of the command station/booster.

Presumably to allow throttle control via the command station , he’s not proposing to override the command station DCC 

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Hi,

 

Because of the way RailMagic works it may not be possible to interface it to existing software.

It seems to generate a stream of position and speed data which it uses internally to control the speed of the train.

 

Existing software uses layout mounted specified location sensors (a loco just passed here messages) and then rely on the repeatability of the DCC decoder and the loco pickups to stop a loco at a certain place.

 

Regards

 

Nick

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1 minute ago, Andymsa said:


want is one thing, actual reality is another. Your basing your thoughts on how railmagic works on speculation. 

Well it’s all speculation until it’s confirmed. But based on reading the manual it’s not capable of triangulation all its doing is “ remembering a flux or field orientation pattern at a known point “ when it sees that “ pattern “ again the tracker in the loco reports it’s at the known point via the DCC link which is detected by the Railmagic box 

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22 minutes ago, NIK said:

Hi,

 

Because of the way RailMagic works it may not be possible to interface it to existing software.

It seems to generate a stream of position and speed data which it uses internally to control the speed of the train.

 

Existing software uses layout mounted specified location sensors (a loco just passed here messages) and then rely on the repeatability of the DCC decoder and the loco pickups to stop a loco at a certain place.

 

Regards

 

Nick

I think all Railmagic does is spot detection , It does  not Re compute position as it moves based on triangulation , it merely report a spot position reached and used BEMF dead reckoning in between “ spot “ detection 

 

You can do exactly the same thing with lineside spot detectors and Railcom speed feedback. ( which is actually independent of BEMF and  hence much more accurate )  

 

Railmagic still needs loco speed profiling because you have to relate BEMF levels to actual forward movement. 
 

all in all it’s a spot detection system at heart. 

Edited by Junctionmad
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4 minutes ago, Junctionmad said:

Nick. Continuous position updating would be a game changer. But it looks like Railmagic doesn’t do this. It seems to build a pattern of the fields at a specific series of known points on the track. It then uses BEMF to essentially dead reckon from  that known point 

 

Given that’s seems to be the case. This is essentially just another spot detector system. It suffers from all the issues of spot detection ( ie block occupancy is hard to do , what about rolling stock in the section etc ) 

Hi,

 

If the tracker is providing speed info back to the RailMagic control unit (why else would it be connected to the motor terminals) then when a magnet is not within range then it uses the speed info to work out where the loco has got to. Existing software does not do this as it gets no regular speed feedback.

 

I agree it doesn't cover rolling stock detection.

 

Regards

 

Nick

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4 minutes ago, NIK said:

Hi,

 

Because of the way RailMagic works it may not be possible to interface it to existing software.

It seems to generate a stream of position and speed data which it uses internally to control the speed of the train.

 

Existing software uses layout mounted specified location sensors (a loco just passed here messages) and then rely on the repeatability of the DCC decoder and the loco pickups to stop a loco at a certain place.

 

Regards

 

Nick


:banghead:

 

it does not produce any current actual position data. How many times does this need to be explained.

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8 minutes ago, NIK said:

Hi,

 

If the tracker is providing speed info back to the RailMagic control unit (why else would it be connected to the motor terminals) then when a magnet is not within range then it uses the speed info to work out where the loco has got to. Existing software does not do this as it gets no regular speed feedback.

 

I agree it doesn't cover rolling stock detection.

 

Regards

 

Nick

The net effect of whether you simply do speed profiling , ie the relationship between commanded speed and motor speed , or whether you use BEMF and equally a speed profile calibration to relate BEMF to speed over the ground is somewhat a moot point 

 

given fixed gearing both derive the same information ie an estimate of distance covered. Both are “ estimates” neither is actually doing direct measurements ( which a continuous positioning system could do) 

Edited by Junctionmad
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12 minutes ago, NIK said:

Hi,

 

If the tracker is providing speed info back to the RailMagic control unit (why else would it be connected to the motor terminals) then when a magnet is not within range then it uses the speed info to work out where the loco has got to. Existing software does not do this as it gets no regular speed feedback.

 

I agree it doesn't cover rolling stock detection.

 

Regards

 

Nick

You do appear to be deliberately obtuse. All the systems use some logic and calculations to say “this train was at X position, travelling at Y speed, therefore it’s now here”. Whether that’s done by profiling the speed of a loco and defining the length of each block, or by using back EMF, or magic, it’s still the same. It’s deducing where a train is until it is told the next position.
 

Regular speed feedback is no more useful than knowing a loco is at speed step X and that means Y mm/second covered, if I held my finger in front of a loco either system would fail. Railmagic is not a solution in this respect. It is not providing real-time position info.   

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Note the reason he’s doing his own decoder and has issues with BEMF in other decoders  is that to measure BEMF he needs a “ quiet “ period in the motor drive waveform to sense accurate bemf. He may be finding that difficult to achieve. 

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4 minutes ago, njee20 said:

You do appear to be deliberately obtuse. All the systems use some logic and calculations to say “this train was at X position, travelling at Y speed, therefore it’s now here”. Whether that’s done by profiling the speed of a loco and defining the length of each block, or by using back EMF, or magic, it’s still the same. It’s deducing where a train is until it is told the next position.
 

Regular speed feedback is no more useful than knowing a loco is at speed step X and that means Y mm/second covered, if I held my finger in front of a loco either system would fail. Railmagic is not a solution in this respect. It is not providing real-time position info.   

True. However BEMF sensing has some advantages over simple speed profiling from commanded speed as it “ in theory” takes into account load changes etc. “. However in practice it can be very difficult to accurately characterise the relationship between actual motor speed and bemf 

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10 hours ago, Grovenor said:

I don't see any relevance to loconet as the railmagic stuff is all downstream of the command station/booster.


it is only down stream on the track feeds. But data still needs to go back to the command station via a data bus. For me that is loconet

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