If you’ve watched the special features on The Dark Knight Blu-ray, then you saw a functioning repelling device that special forces use occasionally. At that time, the size was akin to a carry-on suitcase.
Known on YouTube as the Hacksmith, the man originally came up with his own device, called a repelling hook. He’s gone a step further by creating one of Batman’s most useful and oldest gadgets. He created a grapple gun that launches a Bat emblem grappling hook 150 feet with a great deal of accuracy.
You can find on his YouTube channel a playlist documenting the creation, from initial design to the first tests, to the finalized product. Throughout the process, commenters urged him to also make a grappling hook, which inspired him to create the grappling gun. He’s combining the two gadgets so one can ascend and descend with the same device.
His next step is to enable the grappling gun to have a controlled rapid ascent. One of his videos even previews this device that he and his team are working on. The video below is the first step: the repelling hook.
The Hacksmith has even made his own Batarangs. No word on if an EMP Rifle or a Sticky Bomb Gun is next on his list to manufacture.