High speed car assembly: Not all about robots

A glimpse of the Model 3 Assembly Line from outside the Tesla Factory

Last week, I got the opportunity to tour the Tesla factory in Fremont. It was fascinating to see the many Kuka robots and especially the giant Schuler SMG hydraulic stamping press, the largest such in North America and 6th largest in the world. Also got to see the coveted Model 3s being built and even got a glimpse of the new super high speed SMG stamping machines that Elon Musk Instagramed a few weeks back (click embedded image below to see it in action).

Not long ago, I also had a chance to visit Toyota’s Kentucky plant (one of the largest US auto plants) and there are many similarities between the two. Certainly the heritage of the erstwhile NUMMI plant likely has a lot to do with the similarities. e.g. the manner in which the tour itself was conducted is quite similar. However, there are many more robots in action at the Tesla plant — notably the army of Kuka ones. As this really good article states, Toyota takes pride in the human factor of automation. However, this maybe changing and giving way to more robots.

Model 3 Production S Curve. Source: Tesla.com

It all comes down to assembly speed. Tesla is hard at work to ramp its Model 3 production to meet the unprecedented 500K pre-orders for a first-gen car model. Their goal of 5000 vehicles per week is not so high a target and pales in comparison to volumes produced by Toyota, Nissan, VW and Hyundai at their largest plants. While Toyota pioneered Just-in-Time, Lean Manufacturing with the Toyota Production System that produces a vehicle every 55 seconds at the Kentucky plant, as this articles points out, Nissan’s Sunderland plant produces two vehicles a minute and Hyundai’s Ulsan plant, the largest in the world, produces a car every 20 seconds!

Software assembly is becoming key to production speed

The one aspect of modern car assembly that is less talked about is the time it takes to load all the software into the vehicle at the end of the assembly line. As cars become more software driven, the size of the software binaries for ECUs and domain controllers in the car is increasing resulting in longer flashing times to load software images to cars.

Tesla’s Over-the-Air updates usually takes over an hour. Considering these are incremental updates to existing software in the vehicle, one can think of the time it might take to flash all the software in the assembly time. Typically, car makers use flashing tools in the assembly line to program the ECUs directly to each device or via diagnostics ports at low transfer speeds. Certainly using secure WiFi to load the latest software onto the vehicles at the end of assembly is one way to address this challenge. Having multi-gigabit Ethernet as the communication backbone in the vehicles is another aspect that helps shorten the transfer speeds significantly. These are technologies Tesla is leading with and other OEMs are fast catching up especially the many new EV makers looking to launch their vehicles.

Make or Break

It remains to be seen if Tesla will make history and end up breaking records by delivering the 500K Model 3s in the next 18 months. I’m optimistic having seen the assembly line first hand. Certainly the way cars are architected, made, driven and utilized is changing fast.