You’re unlikely to get that kind of timing with mesh protocols like zigbee and zwave. There’s no forced sequencing with mesh – – messages can and do bounce around the network before they arrive at the hub, and you can’t be sure of what order they’ll take. For this reason, the usual rule of thumb is not to try to schedule things closer than one minute apart. CoRE will allow you to write a piston which schedules things closer together, but there’s no guarantee it will work.
You can certainly do what you’re describing, but you need to take one of two directions.
Approach 1: no network
The most certain would be to take the network out of it all together. Just put a pressure Mat on each stair, and have each of those mats wired to complete the circuit for your LED, and it would all work perfectly. Step on a mat, the light comes on. Step off the mat, that light goes off. Hollywood’s been using that method in movies since the 1930s. It will work great, but it will require a mat switch on each stair. So you need to be very careful that you don’t create a tripping hazard.
The same idea but a little more high-tech would be to use a light beam and diode on each stair where breaking the beam causes that stair’s light to come on. That removes a tripping hazard. This is essentially the same technology as you’d use for the garage door obstacle detection. Again, timing should be perfect.
You can also do this with motion detector lights, although you might have to use masking tape on the lens to get the detection area small enough. But you could just buy some battery operated stairway lights, like Mr. beams, put colored translucent plastic over the light portion And you’d be done. Again, no tripping issue. Timing might be a little trickier to get perfect on these than with the other two because the motion sensor detects a wider area, but with some trial and error you should be able to get what you want. But those are not going to wire into your existing LED strips as easily, so it’s more of a project.
Any of these should work well, and give you the ability to go up one step, jump down two, go back up one, etc. and get the lights to light up as desired.
Approach 2: WiFi
Alternatively, for millisecond timing, you need to look into a Wi-Fi system. Wifi has forced sequencing, which is why it’s appropriate for streaming music or video, while zigbee and Z wave are not. In this case you could just use one detector at the top of the stairs and then create a ripple downward effect if you want, or have a sensor on each stair. But you could certainly set it up so that you get a rapid sequence.
But for this to work, you need to take SmartThings out of the picture for anything other than starting the initial sequence. Once you add the cloud round-trip, you’re going to be above the latency level you’re looking for.