Looks like my “hardware-dead-end” has moved OS-DBTC to a much better hardware design. The new design uses a DFRobot Bluno Beetle (DFR0339) board and a Pololu DRV8801 motor driver board and battery power. Unless I have missed something important (once more) the functionally match between the DFR0339 and DRV8801 is nearly perfect for OS-DBTC. This design is also something that is not beyond my hardware capabilities, and provides a smaller and more flexible footprint that is a much better potential fit for HO locomotives. Bob
I finished porting (complied and code-reviewed) the firmware code for the atmega328p as implemented on the Bluno Beetle board. Now the wait is for the Beetle boards to arrive from oversees (~1 week). As an American, I sure would like to be buying and using American hardware! The BlueTrain3-Test-Breadboard will be reworked for the new hardware design, and then the firmware testing/debugging will start. The BlueTrain3-Test-Locomotive will also be reworked for the new hardware design. I am looking on eBay for HO locomotives that will be good candidates for the interior installation of the hardware. My take on the criteria is: HO, non-DCC, accessible fly-wheel for adding the tachometer-sensor, and plenty of available interior space (for my not-so-good hands and eye sight). I will probably be adding a circuit to provide power from the track in place of the battery (already have the necessary hardware from BlueTrain1). Locomotive recommendations? I picked up a very nice 8-40 locomotive, but it is of the old design (split-frame un-isolated motor), and would take a lot of frame cutting/grinding to make room for the hardware. It is defiantly not a good first candidate. Bob
if you want, I can send you an Athearn, I can isolate the bottom motor brush from the frame, and pop on an sub breakout pcb for the wiring .. at least those have easy accessible flywheels
Thank you! My limited knowledge of locomotives is limited to a few B’man products. I need room for the Beetle-board (28.8mm X 33.1mm), the Motor-board (15.3mm X 15.3mm), a kluged-power-unit (TBDmm X TBDmm) and connecting wiring. The Beetle-board-Bluetooth-antenna also needs ~2mm of free-space. If you want to PM me with some pictures of the insides, the insides of the shell and a shipped-price (just need pigtail-wires on the isolated-motor and isolated-trucks), I will see if I think it is something I can handle. I was thinking more along the lines of a steam-loco with large-tender. Bob
The shell is 3.1cm wide by 16cm inside ..and depth is 3cm.. Inside motor height is 2.2cm, over flywheels 1.6cm, and over trucks is 1.4cm So it would give you clearances of 0.8cm, 1.4cm and 1.6cm If there is enough room for the 'stuff', just pm your mail address ... I'm kind of curious to see this 'mobile'
The B’man FTB I have is just ~2.5mm wide, so I was not looking at this locomotive style. Your locomotive looks to be challenging but doable. And if that is a die-case-shell, it would also be interesting to see how the Bluetooth performs with the shell on. Your locomotive also looks to have a good bit less weight which would also be useful for some of the tests I will eventually want to do. It would be best to wait ~month for me to get my breadboard testing far enough to be sure that I am not at hardware dead-end first. I will PM you with my address when this happens. Thank you! Bob
This “Mark-Magnet” has been tested and it activates BlueTrain3’s Mark-Interrupt signal. It is a “Supermagnet N35 6x9mm Cylinder” (5 for $3 shipped). It is attached with a little double-sided carpet-tape. Bob
Hi Bob, just wanted to chime in that I'm interested in this, particularly if the command packets follow DCC++ protocols. I'm not convinced wifi is the right way to go yet (mostly my ignorance). My interest differs in that I want to used JMRI VSD, and also wouldn't mind an automated fiddle yard, so direct connection to a throttle may be less than ideal for me.
Simon, Thanks for sowing interest. But OS-DBTC locomotives are not using DCC++ or DCC protocols. The OS-DBTC locomotive command set is much more extensive than DCC because it implements a “smart” locomotive capable of autonomous operation. An unlike DCC it is a true bidirectional interface to/from the locomotive. The same basic hardware boards could be used with an Arduino Sketch to implement the DCC++ protocol over Bluetooth. Bob
The B’man FTA/B shells have more room (wider) than I thought from just measuring the frame. So I will be using the B’man FTA/B DC units that I have for the first several OS-DBTC locomotives. So I will not be needed the Athearn locomotive. Thank you! I have been making good progress and should have the new hardware in the BlueTrain3-Test-Locomotive along with functional firmware in a month or less. Bob
The breadboard using the Beetle (DFR0339/DVR8801) is up and running the BlueTrain firmware and being controlled from the BlueCmd software. The breadboard can also be downloaded with an Ardrino sketch and controlled with a serial terminal. So the next major step is the BlueTrain test locomotive with the Beetle hardware. The plan is to use two connected (3 wires) FTB DC locomotives. One will be a dummy that just provides the motor and circuit voltages from generic track power (already have the needed electronic parts lying around). I am also looking for some suitable “power” boards that would be “HO” size or at least a good hardware design so that I will be able to get rid of the power circuit that I will be kludging together. Bob
Not-so-good-eyes and shaky-hands make for slow progress. But the BlueTrain test locomotive is coming together. Just four more solder connections left. If it were not for the “needle” (see picture) that lets me put a controlled amount of solder on the connections, there would be two or more pads solder together. If my fabrication/soldering has not already created a fault somewhere, then the locomotive should be up and running on a ~9 volt battery in a week or so. I am tired of this difficult soldering so plans have been changed from using track power to using two 7.4V LiPo batteries. 7.4 volts will go to the Beetle board and either 7.4 or 14.8 volts will go to the motor diver board. This will allow the firmware to be tested at approximately the two extremes of motor power. After testing, I have dreams of taking the completed setup to a major train show. The setup will demonstrate open-source Bluetooth, but the real show will be a “smart” locomotive automatically shuttling a freight car form one siding to another and then back again with the only a few magnets in the track. This will all be in the hopes that it will motivate some train manufacture somewhere to take up this readily available technology. Bob
This will (hopefully) be the first non-test OS-DBTC locomotive. This used “Slovenia” 2-8-0 steam locomotive has been disassembled and cleaned. It is ready for installation of BlueTrain3 (Beetle/DRV8801) hardware power by track power. The first step will be to add a tachometer-wheel and IR-tachometers-source/sensor to the flywheel. This will require the fabrication and attachment of a “bracket” that will hold the sensor in a stable location ~2mm in front of the tachometer-wheel. I am still looking for a suitable existing small power-board (any and all help appreciated). This board must be HO-small and convert DCC-track-power to max-V-motor-power and to 5.2-7.9-V-Beetle-board-power. Bob
How about an ordinary buck converter, set it to maybe 12v, and depending on current, just use a diode chain to drop feed to the beetle??
Don’t know what a “buck converter” is, I am basically a “board” man. In the past I have put what I need together from soldered-parts (rectifier/reverse-voltage-protection-diode/voltage-limiter/capacitor) covered with liquid-tape (BlueTrain1). Just hoping to find an existing package that will reduce the effort. The BlueTrain3 breadboard uses 2 diodes to make sure that the 9V battery doesn’t do the Beetle-board in. For BlueTrain3S and latter I plan on using a regulator so that the locomotives can take full advantage of different HO track signals/voltages over as wide a range input voltages as reasonable. Bob
'buck converter' is a common term for low cost DC-DC step down voltage converters, bridge, caps, adjustable voltage regulator on on every small board, cost is usually around a dollar, for a 4v drop, a diode chain will take up the same space and roughly same cost a a TO-92 fixed regulator
Interesting but (unless I miscalculated) the maximum Beetle-input current (5.2-7.9V) needed is <100mA for this application. The maximum motor-current needed is 1A continuous and 2.8A peak. Bob
Been working of the steam-loco while waiting for the test-loco’s LiPo batteries. Got some preliminary work done including the fitting and installation of the front LED light. The TCSDCC connector-wires was not cheap but it sure has a pleasure working with some wires that weren’t made by “the-lowest-bidder”. The LiPo battery package (intended for use in RC Quadcopter) just arrived so it is back to the test-loco. The two 7.4V LiPo-batteries weight ~7 oz, and appear a bit big for installation in typical HO boxcar. The power-wire-size is obviously overkill for an HO-loco, and would require some careful reworking for a nice installation. Just figured out that the power-wires can be completely cut off and sealed. The charging cable is big enough for HO (>600 mA). Also a full charged 7.4V LiPo can be 8.4V! Bob
The BlueTrain test locomotive didn’t survive my not-so-good-eyes and shaky-hands. It was basically dead on arrival after two unsoldering/soldering attempts to correct two crossed wires. So after I mope around for awhile and eventually re-motivate myself, I hope to get back to working on the BlueTrain steam locomotive. I hope than having more room for the hardware and using a lot of connectors in the steam locomotive will compensate for my hardware limitations. So it may be months before there are any more of my posts to this thread. Bob
