Toyota Motor Manufacturing Canada (TMMC)
I joined the Assembly Engineering department at TMMC in the winter of 2023 for my second co-op term. I implemented process optimization activities and practiced kaizen (continuous improvement) on an assembly line churning out about 1000 RAV4 vehicles per day.
Being heavily immersed in the Toyota Production System and learning all the intricacies of what it takes to create a quality vehicle from start to finish was an incredible learning experience.
TL;DR I learned how quality vehicles are manufactured efficiently.
Post-Production Option (PPO) Process Reduction
TL;DR I optimized accessory installs by integrating them into existing processes, saving $626,000/year.
Options and trim levels allow Toyota customers to customize and tailor their vehicles to fit their exact needs. Options are also a massive slice of Toyota’s revenue; providing customers with different price points and eye-catching features.
Within the manufacturing process, option installation is often overlooked and inefficient. Since these installs were the only off-line processes within the entire assembly shop, they resulted in significant muda (waste).
Process Muda
Originally 90,000 vehicles per year were driven off the normal assembly line to have accessories installed. The installer then drove the finished vehicle to the lot and walked back.
All in all, over half of the working time in this area was non-value added.
Countermeasures
6 accessories were chosen to be integrated in-line.
Integrated into an existing trunk cargo mat process. $30,000 savings.
First Aid Kits:
Multi-charge Cables:
Integrated into existing owners manual glove box process. $42,000 savings.
Integrated into in-line rear view mirror install process. $66,000 savings.
HomeLink Mirror Option:
Body Moldings:
Designed a new process in vacant space to improve install efficiency. $85,000 savings.
Blackout Emblems:
Designed a new process in vacant space to improve install efficiency. $90,000 savings.
Door Edge Guards:
Designed a new process in vacant space to improve install efficiency. $313,000 savings.
2. Back-to-Back Vehicles. A problem arose with back-to-back, 3-install vehicles. The “over-takt” area would fill up causing line downtime. There was also no way to even-out work (Heijunka). I had to make a judgment call. Is the increased risk of down-time worth the efficiency increase?
The short answer was yes. By taking the historical order of installs passing through this particular assembly line, I was able to simulate the downtime per day due to back to back installs.
All blue bars surpassing the orange “over-takt” limit signifies a simulated line-stop. Across 60 days of historical data, the maximum downtime was projected to be 2m27s over 16 hours of productive time. This relatively minor stop to production was deemed acceptable given the large benefit of the activity.
3. Unpackaging. Since these accessories were delivered in cardboard packaging, there had to be sufficient time for installers to unpackage on a moving line. The challenge became allowing for unpackage time while meeting the Takt. Due to the periodic nature of these installs, we were able to fit unpackaging in as period work.
All in all, by thinking outside of the box and implimenting innovative process design, I was able to improve overall accessory install efficiency by 56% within the TMMC-W plant.
Implementation & Analysis
The goal was to integrate these six accessory installs into in-line processes. 3 into existing processes, and 3 as a new process. This included repurposing unused line space to design a new, more efficient process.
There were multiple challenges associated with moving PPO accessories in-line.
1. Cycle time. The cycle time of a vehicle with two installs fit safely within the 52s takt time. A 3 accessory install vehicle ran over the takt time into an extra pitch. The proposed solution was an “over-takt” area.
Due to low install volume of 28%, this “over-takt” area was used to catch up on longer install vehicles.
Impact
Due to efficiency improvements from 6 accessories moved in-line, I eliminated 2 un-needed processes for a total savings of $626,000 per year.