The sign gives a reaction to speed

Electronic roadside signs in Perth and Kinross smile at drivers who approach them within the speed limit, and grimace at those who fail to slow down.

Transport department spokesman Chic Haggart said the radar controlled signs have been sited outside schools and are as much a classroom aid for teachers as a reminder to motorists.

"We're trying to get the kids to buy into the concept of driving at a sensible speed," he said.

Mobile unit

The scheme has also generated interest from Tayside Police and will be operated by traffic wardens.

The face is designed to be moved around, and can be set up quickly in areas where local residents have complained about speeding motorists.

As with traffic 'guns', the speed of the oncoming car is detected by radar.

This is not about punishing people, we want to change the culture Chic Haggart, Perth and Kinross Council

"The effect is quite marked with those travelling at excessive speeds and it has been very positively received so far," Chic claimed.

Motoring organisations like the Automobile Association (AA) have given the smiley face a welcome.

"People are rightly penalised for speeding," said the AA's head of policy in Scotland, Neil Greig.

"But careful and responsible drivers don't usually get praised for their good behaviour.

"We have no objection to this, if it makes people feel better."

Growing success

Police in the Highlands are already using the signs and Ayrshire is experimenting with them too, according to the company behind the smile, Counters and Accessories.

"We've had lots of interest since we started importing them from Germany a little over a year ago," said company spokesman Tony DiMonaco.

Tony said some councils were sceptical at first: "I remember giving a demonstration to a road safety officer in Barking.

"At the start he said 'I don't like this it trivialises speeding'.

The face is designed to be moved

"But within half-an-hour of seeing it in operation, he was all for it."

Chic Haggart considers that although the smiling face may be eye-catching, it is anything but a gimmick.

However, he does admit the effect of the sign may wear off with driver familiarity.

That is one reason, he said, why the signs are constantly moved around.

"We are most concerned about where we have vulnerable pedestrians, like outside school - but this is not about punishing people, we want to change the culture."