Phil B

This is fantastic, both the real life loco as well as your build. Would love to see the innards though, to see how you packed all the electronics in.

Sure. It gives you a track oval, wheels, magnets, motor and Powered Up battery box. That's always a good start. You can build the train as is, or look for inspiration here (just search for 60197) to see what others have done with this train. Or add all the bricks to your build-pile, and use the train base and other useful parts with your existing LEGO pieces to make your own custom creation. Just a word of warning: This will suck you in deep. Take it from me - I've got boxes full of wheels, track, PowerFunctions equipment etc. that will keep me going for the next few years.

It's not on the US 30% off list, but Europe might have a different list, and there will be 20% off deals as well that are not yet announced. Also, check Amazon.fr to see if they have offers on Friday - 60197 might be part of it.

IDK about LEGO France, but the official Black Friday sales are not until this Friday Nov 29th, the real Black Friday. This weekend was a VIP pre-BF event with double points. There might be more offers coming this Friday, potentially at other retailers.

If you are concerned about the performance of the EV3 motors ... note that you can control a PF train motor from an EV3 brick in at least 2 ways: 1. By making a custom ev3 -> PF cable. Instructions can be found in my answer to this StackExchange question: https://bricks.stackexchange.com/questions/2325/how-to-use-power-functions-with-mindstorms-ev3/4743 2. By using a MindSensors PFMate. This custom component, together with its EV3 code block, allows you to control up to 4 PF IR receivers from 1 port on the EV3, so you can use up to 8 PF motors on one EV3 port. Once you have speed and direction control implemented like this, all you need to do is sense a curve (for example by using a gyro sensor in each car) and then control each associated servo to make the car tilt the right amount in the right direction. You can just write several independent code sequences (each starting with their own Start tile) within your program and all these programs should work concurrently. So one program for each car to read the gyro and adjust the tilt, and one central loop to control the PF train motor.

Two-toned color wheels can tell you IF there is movement, but not in which direction the movement goes. For that you need a three-toned color wheel, as I described above.

It only stalls infrequently, and only during speed rampup. I think that it mght just be a temporary lockup due to overcurrent protection.

Yessir. The pictures were taken without moving the wheels, you can see the quartering right there.

And she's done! Here is a video of her running back and forward on some track (click on image to play video): Occasionally, and only while going forward, she will stall and needs a small push to get her going. Haven't figured out why, but it is not a big deal as this happens infrequently. To make all the electrical work, I had first wanted to use a cut-up PF-9V extension cable. Unfortunately, with the length of the cable of the IR receiver, and the extension cable length, there wasn't enough room in this little engine to fit all the wiring. I had to cut up the wire leading to the IR receiver. As I didn't want to permanently turn my IR receiver into a 9V-battery operated unit, I used some cut-up I2C cable to make an interchangeable connection. Here is a sample of how this cable looks like: The full electrical setup is shown below. To access the battery, the roof of the cab comes of, and the top of the engine hood hinges open. The 9V battery is inside, wrapped in black electrical tape as its bright yellow and blue colors were showing through gaps in the bodywork. The batteries are purchased from [url=https://www.amazon.com/gp/product/B07BT4D99D]Amazon[/url], and they come 3 in a pack with a charger. These specific batteries have a stated 800mAh capacity, and deliver an almost constant 8.7V (most Li-Ion batteries only do 8.3V). I'm debating an OKBrickWorks order for some stickers, but otherwise she's done. Thanks for all your input throughout the design and build process!

Two more options that I can think of to detect the direction of motion: 1. Dangle a technic beam vertically under the train, with a touch sensor inside the train on either side. As the beam hits the track sleepers, it will push the top part of the beam against one of the sensors. By reading out which sensor is touched, you know the direction the train is moving. 2. Mount a large 40 tooth gear horizontally (on a vertical axle connected to the driving wheels or any other train wheel) inside one of the carriages, with a color sensor aimed at it. Put a sequence of 3 colored tiles on the gear (or multiple sequences), for example black-yellow-red. As the train moves, the gear will turn and the sensor will detect the sequence of tiles passing under it. If yellow follows red, the train is moving one way, if red follows yellow it is moving the other direction.

Two friends of mine built a computer without a CPU a while back (www.gigatron.io). Their design philosophy was to keep the circuitry simple, and do the complexity in software. So their board has only 40 TTL chips, and an instruction set with 10 commands (give or take), but they've then used this to build a vCPU in software which is much more complex. For this build I subscribed to the same principle: do as little gearing as possible, but instead put the speed differences in code. So each belt has its own motor (with one motor powering 2 belts with a very simple gearing mechanism: one belt gets driven 24:40, the other 40:24) and the speed differences are maintained in code. There is a global "speed" variable, and the relative speeds of each of the belt motors are set in relation to this global variable. One loop keeps updating the motor speed, another loop gradually increases the speed variable until it hits max speed (70% at the moment). This creates the start-up sequence you see in the video.

Excellent model indeed. It might have some issues with R40 curves though :)

Thanks all for the great comments and praise! That wasn't a telegraph pole, that was my custom built tree :) Good eye though! I limited the speed to 70% in the video, but before I did I had it set to 100% and that did lead to some breakage. No video footage unfortunately. Moving the track ties would not have looked good, for 2 reasons: 1) Without a lot of work in building supports for guiding wheels, the track undulates. That's not a problem for bigger objects such as fences, trees and hills, but for the ties, being so close to the foreground, it would have made them look really awkward 2) Moving the ties would also mean moving the track, and those track pieces are too long and would look really weird "flopping" around the turns. If you focus on the engine, you see more things that are not moving when they should (e.g. the front wheel). The thing is that your eye naturally tries to take in the whole scene, and you don't focus on the engine typically. This makes these non-moving parts less noticeable.

Can't you use a single gyro-sensor to measure direction of acceleration/movement, and thus determine which color sensor to use? If you use the Rate measuring feature to detect a change in speed/direction, wouldn't that help? You need to somehow know that you are moving backwards though, and not just slowing down. Alternatively, you could have special calibration tiles on your track, and the sequence in which you encounter them tells your train which direction it is moving in. Interesting challenge!

Click on the first image to watch the video, and I think you'll know what's it supposed to do :)

Here is my submission for this year's OcTRAINber, as run by www.brickmodelrailroader.com: (click on the image to start the video) I know I am pushing the boundaries of the intent of the competition, but according to the rules this meets the objective, and I had fun with it :)

Here is how (as posted by me in another thread): I've downloaded the .dat files from www.bigbenbricks.com and installed the Part Designer app that is part of the Stud.io package. Then, in Stud.io, I changed the selector from "Master List" to "Custom Parts", and clicked on the link that allows you to create a new part. This brings up the Part Designer and gives you several options (design new, design based on existing part, import file). Use import file, import the .dat file from BBB. Then, in the connectivity editor, make a round hole and an axle shaped hole and then save the design back into Stud.io. Do this for both the flanged and the blind driver and you have 2 custom parts in your Custom Parts list in Stud.io which you can now use. Didn't take more than a few minutes to do in total.

That is absolutely awesome! Of course, 11w gives so much more room for details than 6 or even 8w, but you used the extra space to the extreme. Well done!

Welcome! That’s a nice little track layout you set up there with minimal track. I like it!

The power solution hasn't been changed from the original set 7938 - it is Power Functions driven. The first picture (which is a Stud.io render) uses a 9V motor part as Stud.io does not have a PF motor in its parts list :) The picture you looked at was a pre-build render. In the final build there is no asymmetry. See this pic: And here is the additional bogie detail you requested: Wow, thanks for your response! I really liked your version with the moving doors, a feature I unfortunately had to drop due to my design choice of keeping the white 6w train base. I haven't tried it on inclines, but the carriages are not fixed to the bogie - they rest on top of the central cylinder, with the vertical axle (see the pic above) holding them in place. This should give enough freedom of movement to handle some inclines (untested though).

Thanks! Yes, my previous design worked, but didn't allow the rear axle enough movement to prevent stalling. So I had to improvise :) A two-tone 6L bar would have been ideal, but since I do not modify my LEGO pieces (except for some electrical wire cutting which will need to happen to make the power solution for this MOC work) I will not be painting this bar partially red.

I know many people have used set 7938 Passenger Train to build a LEGO version of the Bombardier Talent EMU/DMU; here is mine. I didn't want to necro-post in one of the existing threads, but if I were to, I would have posted here, in cimddwc's thread as that is where I got most of my inspiration from as I was researching certain aspects of this train. My version differs in several ways though: 1. I wanted to keep the original train bases as part of my design (@cimddwc used a custom base to enable his doors to work) 2. I did develop an opening door, but to make it work with the train base I had to have part of the door stick out by 1.5 LDU which ruined the look of the overal consist, so I dropped that plan. 3. I didn't like the folded paper harmonica between the carriages in cimddwc's design, so I came up with a different Jacobs bogie design which makes the train look connected from front to back. Thanks to some sideways brackets there isn't even a gap! Here are some pics and a video (on Flickr) showing the model in action. There is some wheel slippage, likely because some of the Jacobs bogie wheels are not rotating freely enough. I think I can fix that (either loosening them up a bit, or switching to ball bearings. or even adding a second motor into one of the bogies). 7938 as Bombardier Talent by Phil B, on Flickr And the video:

I have strips of bicycle inner tubing around the wheels on one side. When I had it on both sides it caused derailments. In the video the side with the tubing is not visible.

Yep, that should be correct. The gear driving the wheel axle went from a 16 tooth to an 8 tooth gear, so it should turn twice as fast.

Final version - BrickLink and Bricks & Pieces orders have been placed to get all the missing bricks. Which means that you can expect real-life pics and another video in about 2 weeks (US Thanksgiving). German Shunter DB Class V 36 by Phil B, on Flickr