I have a farmer trying to prevent his workers from entering a street through a blind spot when oncoming traffic is detected. he was thinking something along the lines of a camera that triggers a red light when motion is detected and green when it is not. basically these vehicles come up a knoll onto railroad tracks and straight into traffic with little to no view.
I am at a loss as to where to even begin with this.
your thoughts are appreciated.

I think it may be better to use something like IR beams or those long range car sensors its breaking a physical sensor and not a motion window in a camera.

I am not sure how solid any camera is going to be and also what type of liability there is for you to incase someone gets into an accident based on a light not being red and there is a car.

I would not do the traffic light thing. Seems like it is:
1) illegal to install your own traffic light system with out local authority permission.
2) If they get a green light and drive right out in front of a semi = someone is loosing everything and someone probably is going to jail.

2 solutions I can think of.
1] See if he can get the DOT to install a traffic light at that intersection. If it is high traffic enough and dangerous as you say, there is a good chance.
2] Install an IP camera and have a tablet mounted in the vehicle to access it when coming to the intersection. Tablet can also be used for GPS, tracking, to-do lists, etc. for the workers. Challenges would be power and internet access for the camera.

We did a similar situation with a big-ass convex mirror. Would that be feasible?

[Link: reflectionproducts.com]

[Link: duravision.net]

I love that the actual solution is a mirror

That was the old solution but can not get the right angle from the needed viewpoint. Im going to do a site walk and take some pictures so you guys can understand what I am dealing with. I agree with the comment above about a camera not likely to be the proper solution.

If you set up a red/green light you're taking on a great deal of liability.

Big liability issues with any kind of signal..

Only solution is a mirror (used a lot here in Colorado due to numerous blind curves), municipality installing a proper traffic signal, or the land owner reconfiguring their entrance drive.

If this is here in SB county, you're looking at big time fines for any signaling of public roads. However the County Roads dept (off of California ave in Orcutt) is pretty receptive to needed signaling, especially if a public safety argument can be made....

Camera, and a Sunbrite TV.

Speed radar tied to a light or a speed readout display.
Positive speed means traffic in coming; negative meas it's going away.
There are some units that will ignore negative speeds and only 'focus' on positive ones.

Is this on your property? If it is, you MUST investigate the liability issues. I know you're trying to make things better, but the irony is that if you try to make things better and ONE TIME something horrible happens, it's all on you.

If this is on public property, apparently you have to prove to someone that it's necessary. Have there ever been any accidents there? Stage some almost-accidents on video.

It is in SB county. The signal would be in a private field letting the farm workers know it is OK to crest the knoll.

Is the "knoll" still on the private property, or entering the public roadway?