A couple of weeks ago I posted the miniature Trojan horse I made all those years ago. Last year, I decided to upscale the original MOC by a factor of 4. The end result after a few months work was 4kg of moving Trojan horse, consisting four XL motors, two M motors, two battery packs and three IR receivers.
Originally, the legs were driven by an M motor sitting on top of each leg with a reduction gear box in between, however reliability issues eventually resulted in direct driven XL motors being used. At the 2017 Bricks for Woden School I discovered some further shortcomings in the strength of the legs, but luckily I was able to buy some 2 x 4 bricks at the show that worked a treat in reinforcing the structure.
The head is made up of a large number of slope and inverted slope bricks. There is an archer minifig that pops out of the top of the head, and the head itself has a door/mane that opens. The head is secured by a plate at the top, 8 pins at the front of the body and a securing axle to stop the head from falling off while the horse is moving. As the head is removable and the archer motor is contained within the body of the horse, two cogs are used to transfer torque allowing the head to be easily removed.
The undercarriage ramp is used to release attacking minifigs from inside the horse. The ramp is driven by a large actuator connected directly to an M motor and comes to rest on a boardwalk that doubles as reinforcement for the legs. Additionally, the top and side of the horse open to reveal some more minifigs preparing for battle.
At the rear of the horse is a removable tail (with a minifig clinging on for dear life) that reveals two battery packs. The first battery pack drives two IR receivers, the first connected to the archer and ramp, and the second connected to two XL motors. The second battery pack drives the remaining IR receiver and two XL motors.