I have an outdoor dog with a big backyard fenced off with a gate and it tends to run off if we don't tie it to a leash before we go out. Although it is not a big problem (the dog will only be tied for few hours without anyone at home sometimes, don't worry it has food and water nearby), it would be easier if the dog was released when we leave the house without it trying to escape. We do not wish to use an electric fence or other electronic/shock devices on the dog, just wondering if there is something like a leash/chain with a timer lock that will automatically release the dog after a preset time. Any other "less-physical" suggestions for preventing a dog from escaping would greatly help. Thanks.