John Hill

Hello, I am considering Ultra Wideband Realtime Location System for Lego train layout. The idea is each train carries a small (unfortunately not tiny) electronic system ( a 'tag') that controls the motor(s) lights etc and determines the train position in relation to two (or more) 'anchors' and has a WiFi connection to a 'controller'. All these units are similar being ESP32 micro controller and a special Decawave D1000 chip. The tag units of course also need an H-bridge to control the motor. This is how it works...... Two (or more) 'anchor' units are placed in position near the layout. The anchors and the tag units are in almost constant communication with each and every other and the distances determined by 'time of flight' in this way each unit has the distance determined to every other unit and in this way the position of the tags in relation to the layout is determined and can be read by a PC connected to an anchor unit. There could be a track plan displayed on the PC with the position of each train (tag) displayed in real time. Software on the PC could send commands via wifi to each tag to control the train. I see attractions of this system as including ease of fitting to any layout including temporary combined layouts at displays etc, this system solves the need to determine train position and to control the train. The system is equally applicable to all Lego train systems including heritage 4.5v trains, 12v trains, 9v train and battery trains on plastic rails. All train types including DCC converted trains could continue to use their existing control systems while being visible on the control display. 4.5v battery trains could have full control and position reporting. 9v and 12v rail powered trains could also be controlled and position reported, in these cases track power could be left at full speed and the train controlled by the new system. 9v and 12v trains could carry a battery and run on plastic rails, in fact all trains could run on plastic rails provided they carry a battery. The cost? Not really cheap but for comparison if I took my wife to a cafe for coffee and a slice of gateau that would likely cost more than the price for one of these units. John

I know I risk being banished from the forum forever but have you considered cutting a track to fit?

I have a couple of files boxes filled with Lego instructions etc so if anyone should want to buy my collection I can point to those boxes and say that all the bits from those sets are present and correct in the collection, plus of course a few thousand bricks and random other stuff from alternative manufacturers. I have found Lego to be very durable and I am not aware of any of my 4.5v railway stuff from '70s that has given up the ghost. I do however keep my Lego in a room that has no windows and has a filtered air supply so even white bricks are (mostly) still white and of course dust is not an issue.

Deleted by me! Invalid thinking on my part! John

Hi, there is quite a puzzle as I cannot imagine how to reverse the motor even if I wanted to! Did you slide the motor armature out of the magnets? Maybe putting the magnets on back to front will cause the motor to run the other way.......I am not sure. John

I am sorry if you did not understand my post. I was suggesting a bar code under the train and a trackside sensor to read it and identify the train and which direction it is going.

Finding the position of the trains is a real challenge especially if you want a system that will work with all the different Lego train types. One system may be that you have trackside sensors that detect when a train goes by, identifies the train and the direction then that information must go to your control centre. At least with trackside sensors you can use wires back to train control and there is potential for train control to signal back to control track switches (points). I am thinking that the sensor would need something like a Arduino and the train would need some marking that could be read by the sensor, a bar code underneath perhaps?

Controlling the switches is something that is too easy to over think! Look at the switch and we see that only a small bit (the 'frog') actually moves and that it is moved by the lever and a spring. No matter which position the lever is in the movable track frog can be easily moved to the other position. The easy way to remotely control the switch is to thread a piece of string (please use only genuine Lego string!) through the lever side rail and glue the end to the moving piece of the switch. Move the switch to the turn out position and leave it there and just pull the string when straight through is required. You can use whatever mechanism you like to pull the string. It is true that string is not ideal for the job and perhaps a stiff wire could be bent to do the job.

Most of my collection is comprised of sets I have bought over the last 45 years and from 'collections' I see advertised on our local 'TradeMe' auction site. It seems people might collect Lego over decades then eventually their stuff goes to auction and a great bargain for other Lego fans. Of course sometimes I need something that is not in my collection and it is very convenient to buy that at BL. Building a whole project from BL purchases? Bound to be expensive.

I aint clicking on that!

Hi, there are some ways you can solve your problem, some cheap, some not so cheap. You may be interested in this topic.. http://www.eurobrick...opic=120012 it says for 4.5V trains but you could do the same for 9V motors. You would need a simple little timer circuit to turn the power on and off to the track segment. Or maybe this one, more expensive.. http://www.eurobrick...howtopic=120326

Hi Joel, of course you can put your battery in a box car and that is exactly what Lego did with their earliest train sets. However there is a bit of a challenge in that if you build the box car with the common Lego bricks there will not be much room inside for the battery and you really need to be able to get to the switch etc. You might find an old 4.5V Lego battery car on Bricklink (and other sites) but be careful and make sure it is in good order as many have been damaged by battery leakage over the years. The battery car has an external switch that can stop/start and reverse the train but if you want to use that type of battery car you would need a 4.5V Lego train motor. There are other ways you could make your battery Lego train and there is plenty of advice right here if you are uncertain about anything. P.S. I have been running Lego trains since 1973 so you can think of them as an 'investment' for your future! John

I think this would be very useful in the way you suggest but I use DCC and if I had one of these I would use to to pick up track power for passenger car car lights. I would also use your device to power 12V motors that I now use with DCC and very unsatisfactory wire brush pickups. There are several ways this could be useful to the community, in my opinion.

I am not a Lego purist but no matter how good the clones may be I will likely also continue to buy Lego. One of the clone sets I bought was a Sluban(?) train which I eventually consigned to standing on a siding as a bit of background filler, that set has a one piece steam loco with six wheels which is unable to follow Lego curves but the fix was simple as I took out the middle axle. All in all an OK purchase but not one I will be repeating.

Thanks very much for the information! John

Our train layout is 4.5V battery trains, 12V 'centre rail' (two rails actually) trains and 9V metal trains. Several have been modified for example 4.5V running with rechargeable batteries, 4.5V running with radio DCC, 12V and 9V trains running DCC. But now I would like to know about PF components for trains which I think are infra red controlled with rechargeable batteries? What components do I need to buy to get started with PF trains? Oh, am I right in thinking PF is the present technique for LEGO trains?

Suppose you want a very simple sequence such as the train standing at a station starts and runs around the track before returning to the station and stopping until the button is pressed again, this would be a very simple thing to do with not much more more than a simple push button. First you must electrically isolate one or two sections of track from the others and the easy way to do that is to insert a layer of insulating tape or even paper where the rails join. Connect the power controller to the remaining track in the usual way and check that the train will run around the track and that it stops when it comes to the isolated section. Connect a push button switch between the main track and the isolated section and check that pushing the button causes the train to start. It probably took me longer to type this that it would to actually do this.

There are a number of quite simple things you could do depending on what type of trains you are running.

Hi, yes the train runs off the LiPo which is a bit less than 4 studs by 8 stud and takes up most of the floor of that little wagon. The wagon has 12V power pickup underneath and will take a charge whenever it encounters about 3V or more on the sections 12V conductor rail. I should have put the train on blue plastic rails to make that all a bit clearer.

Lets have another try with that video.. http://vid1240.photo...ow radioDCC.mp4

My 4.5 volt battery train on radio DCC! This is the best thing you could do with your battery trains! This is the kit as received nicely mounted on a card for testing prior to fitting to the train. The hand held radio control that can control several locomotives, electronics on the card including the radio module along with the DCC controller chip and voltage converter and battery managment circuit. The LiPo battery and a pencil with a magnet on the end used to operate the magnetic switch on the battery electronics. The controls and battery mounted in a short Lego wagon.. Of course there is the obligatory video of the train in motion.. The S-Cab equipped 4.5V battery train running very smoothly at near its lowest speed setting. Google S-Cab to learn about S-Cab radio DCC and where you can get the necessary parts.

Here is a video... Lego Train Reversing by MrJohnHill, on Flickr .....I hope it works as I have sweated blood to get this uploaded etc. The first train has 4 NiCd size AA the train in the video has 4 AAA alkaline cells.

The train stops about one third down the rail. I am working on the second one of these so that I will have two battery trains to play with and will think about a video when I get it all running.

Ooops! I had a few errors in the circuit and have made corrections to it.

Start, stop and reverse for 4.5 volt battery trains.. Sure, Lego supplied track side stopping and reversing devices for the 4.5 volt battery trains but this is something different, this is a method of controlling your battery trains remotely by electric means. The train runs on batteries in the normal way but when it reaches the conducting track one of three things will happened depending on if the rail is energised and if it is which polarity it is energised. If the conductor is not energised the train will continue on, if energised the train will stop and when it is deenergised the train will start again and the direction it goes depends on the polarity. Rechargeable batteries take a charge while the train is stopped. I have a train running back and forth on a section of track where there is not enough room for a layout. I have used a simple electric timer to control power to the conductor sections of which there is one at each end of the track. The train stands until the timer drops the supply to the conductor and the train starts off down the track until it reaches the other end where it stops for a little while then the trains starts off back up the track and the cycle repeats. The circuit is simple enough, the two under train contacts are connected to a rectifier circuit which charges the battery. Two relays are activated by current from the under train contacts, relay number one is a simple relay with normally closed contacts and when activated stops the train. Relay number two is a special type of relay which will move when one polarity is applied to the coil and will not move back until the opposite polarity is applied. Relay number two sets the direction of train travel and the type is known as a bipolar latching relay. I am using 5V relays. Some pictures of the required bits and pieces.. The little circuit board.. The contacts fit neatly under a train wagon.. Little plastic ramps I made for the each end of the conductor rail, without these the contacts are likely to bounce and derail the car..