The pattern lock is an almost impossible to break house design. The possible permutations are far greater than with a normal combination lock. Because it doesn't provide the intruder anything to work with, the burglar doesn't know which actions produce results and which don't. Effectively it's like every tile on the ground may or may not be a switch, as far as the intruder knows.
The owner may further confuse matters by adding in fake switches.
The vault is blocked off by a trap. The trap is disabled if the right switches are triggered. The switches, however, are out of view of the player and triggered by leading cats or dogs to them by walking a specific pattern. However, walking the wrong path, kills or traps the animals, making the puzzle unsolvable.
In this simple (and forgiving) example, the electric floor is powered by a power source running through a switch. Leading the dog to the switch turns off the trap.
If the player walks one tile north from the position in the image, the dog is trapped in a dead end. If the player walks south 6 or more steps, the dog is trapped in the southern part of the house. Only by walking at least 2 steps south but not more than 5, then back north, will the dog trigger the switch that turns off the electric floor.
Varying from this path too much traps the dog making it unsolvable.
This design can be vastly complicated by adding more dogs/cats, who can kill or trap each other.
One can also add timers to force the player to solve it at a specific time.
Unlike with a Combination Lock, the burglar doesn't even know when he has (or hasn't) triggered a switch. The only approach is to just start walking every possible combination of tiles possible. Obviously the permutations are infinitely greater than with a combination lock. What makes matter worse is if the solution occurs while the trap is out of view - trekking back to see if the trap has been released can re-enable it, because it's not possible to avoid triggering switches as is the case with a combination lock.
Therefore it's good design to have the last unlocking step occur out of view of the trap itself, and be sure that the moment it is unlocked, any other action than heading straight to the trap will re-lock it. This could also be done using a timer.