Tramway line - RCX Automation

[PrisonBrick]

This was an experiment of automation of a tramway line with an old LEGO RCX brick:

All sensors and cables are 100% LEGO. There are 8 light sensor, 4 (two couples, one couple for station and one for switch zone) on input 1 and 4 on input 2. 3 output, output A (station 1 - switch), output B (station 2 - switch) and output C (switch zone). Everything is handled by NQC program

[Duq]

Nice! I like the passing station!

I've done a similar thing with a commuting train as well as a train on a loop that pauses at a platform. Can't beat the RCX for this sorta thing.

Do you use a pair of light sensors to shine at eachother? How does that perform? I've used PF LEDs opposite the light sensor.

[zephyr1934]

That is a slick little layout, I really like it (I'm working on a streetcar myself, my first 9v moc in a while, and perhaps I should say this is even inspirational). All in all exceptional work (especially with your station MOCs).

I did a couple of RCX layouts in the long distant past that might be relevant to what you are doing. First, the light sensors in this thread. They use a PF LED to shine in to the light sensor. I put the LED behind a 1x1 technic brick with a 1/2 pin to keep the beam focused on just the sensor and the light sensor having a "tunnel" pointed straight at the LED to keep the ambient light out. Also, I wrote the code so that the first thing it did was to auto-calibrate the light sensors to the ambient lighting.

The other RCX layout I did that is of relevance was a simple one track "ping-pong" similar to your layout only with one train and no switches. I was running a longer, heavier train at a show. By the end of the 3 days the 9v motors were burned out, probably in part due to the PWM of the RCX. You might want to consider putting a capacitor in to the circuit to smooth out the PWM and get something closer to DC.

[Bernie56]

Cool. Are these sensors from the Mindstorms EV3 series?

[bmacro]

Amazing!! Really good job... Compliments!

[PrisonBrick]

On 11/4/2017 at 0:48 AM, Duq said:

Nice! I like the passing station!

I've done a similar thing with a commuting train as well as a train on a loop that pauses at a platform. Can't beat the RCX for this sorta thing.

Do you use a pair of light sensors to shine at eachother? How does that perform? I've used PF LEDs opposite the light sensor.

 

On 11/4/2017 at 7:47 PM, Bernie56 said:

Cool. Are these sensors from the Mindstorms EV3 series?

I've used this sensor: https://www.bricklink.com/v2/catalog/catalogitem.page?S=9758-1&name=Light Sensor 9V&category=[Mindstorms][RCX]#T=S&O={}

A pair of light sensors works fine, but occasionally oscillations of ambient light trigger the sensors... I'll try with a technic brick 1x2 to do a tunnel light