shopping trolleys

[janoel]

What makes a shopping trolley come to a dead halt when their is either a line outside the supermarket or nothing?

[lisaj]

I'm assuming your question is asking what makes trolleys stop outside a supermarket. Trolley's cost a great deal and some supermarkets have put radio triggered brakes on the trolleys so that they can't move when outside a certain range. Question is, how far were you taking your trolley and why ;-) ?

[janoel]

Dear Lisaj I didn't put the question very well, also have used the wrong kind of "their" - sorry about that. What I can't understand is the "Radio controlled" bit - how does this operate ie. does the painted line have some kind of magnetism in it? Outside Tesco's for instance there isn't a line but the trolleys still stop. Yes I have managed to get a trolley past the line sometimes and have wheeled it home because my shopping has been heavy. I have always returned it the same day or at worst the next day!!!!!

[Maxrom]

I don't believe the painted lines have anything special about them. I suspect there is a transmitter located within the store that has a limited range (at least sufficient to reach the furthest parts of the car park for example). Whilst the trolley is within range of the transmitter, and thus receiving a signal, it will operate normally. However, as soon as the trolley is taken beyond the range of the transmitter in the store, it looses reception of the transmitted signal, and applys the brakes. The painted lines are probably provided as a guidline, and reminder for the customer, that the trolley should not be taken any further. The trolley should stop when it reaches the line if the line has been painted accurately, but in reality, depending on how well the transmitter has been setup, and the weather conditions, it may be possible to take it some distance past the boundary before it stops.