If you want to build an actual HAL 9000, all you need is an LED, some carpentry skills, and any laptop accessing a talking AI. If you want to build your own R2D2, you’ll have a tougher job assembling a range of materials, motors, and electronics. But what if you wanted to make your own working version of TARS, that bizarre, blocky robot from Christopher Nolan’s Interstellar that looks like a stainless steel ATM with metal posts for legs sprouting from its shoulders?