There needs to be some signal before any curve, line or other sensor. Are all curves the same radius?

Option 1/ If the power is coming from the track, then a signal could be send to the power supply to turn down/off/even brake is possible.

Option 2/ The car circuit needs to be analysed. Are the motors DC or brushless.

A small chip, I use PIC, but Arduino are popular, connected to a motor controller, that senses the track sensor, then controls power/brake. This needs to be programmed.

Camerart.

 

Just bumping this thread, Ive been busy.

 

Just bumping this thread, Ive been busy.

Are you the original thread starter? Three years off - you really must've been busy!

 

I have a suggestion. Have an IR sensor or something at the start and have it time when to accelerate/decelerate. Then it resets every time it passes it. This way it does not accumulate errors.

 

Just bumping this thread, Ive been busy.

Hi Scott, note that you are registered under two accounts. Choose which one you wish to keep and the other will be deleted.

 

Is this thread worth responding to? Only because I’ve fanatized about the same thing. If you are running the car on your own track, and you can implant markers, it’s a relatively easy proposition. If you are ‘visiting’ another track, or are prevented such markers. it’s a different matter. Possibly, one could deploy an ultrasonic sensor and map the track. While running, you could ‘trim’ the speed with the controller.

 

The idea would be to provide a worthy opponent for your own track when there is nobody to compete against. If your are visiting another track chances are you’re also visiting the tracks owners and likely have a real human to compete against.

 

The idea would be to provide a worthy opponent for your own track when there is nobody to compete against. If your are visiting another track chances are you’re also visiting the tracks owners and likely have a real human to compete against.

I have a concept in mind that might work, but I haven't had time yet to flesh out the details or run a simulation of a circuit. This would not require a microcontroller or programming, although I agree with the others who have said it would be much easier, and give much greater control, if a microcontroller could be used.

The basic concept I have in mind is to put white stripes, or dashes, on the track any place you want less than maximum speed. This could be done with paint, grease pencil, stickers, etc. The distance between the stripes would determine the speed. So something vaguely like this:

• no stripes at all = full throttle
• stripes 3/4" apart = 75% speed
• stripes 1/2" apart = 50% speed
• stripes 1/4" apart = 25% speed

In reality, the circuit I have in mind probably wouldn't be that linear, but I'm just trying to convey the concept for what would be on the track.

The idea for the circuit itself would be to use a charge pump and an RC filter to convert the track stripe frequency into a voltage. The voltage rapidly drifts to maximum in the absence of pulses, and is pulled down towards zero as pulse frequency increases. That voltage in turn could be used to control the motor speed.

I have zero experience with optical sensors, so assuming I'm able to come up with the pulse to speed control circuit I have in mind, we'd still need help from someone else (or just research around the web) to turn the white stripes into voltage pulses.

I'll share a schematic and sim if I manage to make something work.

 

stripes would determine the speed. So something vaguely like this:

• no stripes at all = full throttle
• stripes 3/4" apart = 75% speed
• stripes 1/2" apart = 50% speed
• stripes 1/4" apart = 25% speed

What if the white stripe shut off the power? Kind of like PWM. If the white & black were both 1/2", you would have 50% power. If white was 3/4" & black was 1/4" you would have 25% power.

 

This might be the simplest approach?

When the car comes out of a corner at it’s default ‘ghost’ speed, it could burst for the duration of the straightaway, before arriving at the next corner, returning to the default speed. But how?

The burst could be a time constant derived from an RC charge, discharge cycle. Say one mounted an emitter/receiver under the vehicle, and a reflective tape was positioned on the track. The receiver, when active would charge the RC circuit, which in turn could drive your higher speed power element. By experimenting with the charge and decay resistance, the length of the tape could then become the ‘trimmer’.

 

There is a video online of a solution almost identical to what DNA Robitics has proposed and it appears to work very well. The designer goes into detail about what he has done but there are no plans. There is even a picture of the car with the added components. Check out the link below. You will need to translate it, unless you can read German.

http://slotbaer.de/slotbaer-projekte-digital/28-pd132-d124/38-ghostcar-etikettensteuerung.html

 

There have been some really good but complicated solutions to this. What I am looking for is something that can be put together as a project by the average punter that can read a diagram, solder and owns a slot car track. Perhaps this is simply not possible but I wanted to give it a chance. Simplicity is the key here.

I must have missed the micro/programming part

 

There have been some really good but complicated solutions to this. What I am looking for is something that can be put together as a project by the average punter that can read a diagram, solder and owns a slot car track. Perhaps this is simply not possible but I wanted to give it a chance. Simplicity is the key here.

Hi S,
Previously I've made wire following buggies, that would travel 100-200 mtrs in a loop, they centred using two coils each side of the front of the car. I know this isn't what you want though.

For the cars to know here they are some sort of input needs to be given to them. You mention marks on the track, and unless you want to get into visual recognition or a GPS 'type' system, or some other quite complicated ideas, I think I would go for marks at equal distances around the track, (more = better) and for the car to count them, and be programmed to act at certain counts.

Cheers, Camerart.