In conversation with Hideki Mizuma, Chief Engineer, Toyota Innova Hycross on the development of the new MPV for India

We get talking to Hideki Mizuma, the chief engineer behind the all-new Toyota Innova HyCross. We talk about the updates to the engine, platform, design and also talk about the bid to make this MPV safer. Mizuma san also sheds light on what the biggest challenges were in developing and getting the Innova Hycross on the road. 

Aatish Mishra: The biggest change. You've changed from a ladder frame platform to a monocoque platform. Why was this done?

Hideki Mizuma: For the development of the new Innova, we thought about what is the Innova DNA and what should be evolved. The answer came out to be: one, fuel efficiency. Second, packaging and third, styling. We needed to form the styling of Innova based on the current trends. The monocoque created more space on the inside and for the hybrid technology. This is why a monocoque chassis was a clear choice for us. 

AM: Now in India particularly, the Innova has gained a reputation for lasting very long. More than even 5 lakh km. Will the monocoque be able to last as long as the ladder frame?

HM: So 20 years ago road conditions in India were not so good. At that time the frame structure was very important. But in the current situation, roads are improved and of course, we investigate other vehicles in India as well and we have enough confidence to achieve the Indian customer's expectation. So, yes the new Innova’s reliability is enough. We have confidence in that.

AM: What are the advantages of monocoque compared to the ladder frame packaging? 

HM: The new Innova is based on the new TNGA platform we developed for the MPV. The floor is fully flat which makes the car very spacious and the monocoque chassis also helped in making the car more stylish. The transition from a ladder frame to a monocoque has also made the car lighter by almost 200kg. The monocoque architecture also increases fuel efficiency and performance which makes the car better.

AM: What was the biggest challenge in engineering the new Innova?

HM: According to current Innova’s DNA. The main challenge was to keep the ground clearance and the performance of the new Innova, same as the previous one. Although the platform is shared with other global products we had to raise the height of the new Innova considering Indian road conditions and steep speed breakers. We also simulated Indian road conditions in Japan to test the vehicle.

AM: Now in India particularly, safety has become a big talking point. What have you done to the new Innova to engineer safety into it?

HM: The new TNGA platform is global and is very much durable in very severe conditions and also pedestrian safety-wise from frontal impact and side impact. And also preventive safety wise the new Toyota Innova gets the new Safety Sense. In India, it is very difficult to tune the Safety Sense but after extensive tests, we made a tune which is unique to India. 

AM: Now the big question. Why no diesel engine option in the new Innova?

PB Venugopal, VP, Toyota India: The new Toyota Innova HyCross will come with petrol as well as the hybrid variant. And we will continue with the Crysta diesel. We have only temporarily stopped taking orders for the Crysta diesel but as soon as we are ready, we will be announcing it.

AM: Could you tell us about the hybrid engine and the technology that it comes packing?

HM: This is the fifth generation of the Toyota Hybrid, which is the latest hybrid system. The fuel economy output is much better than the fourth generation. Low friction battery improves the performance of the vehicle. The fifth generation came out this year and the Innova is the second model which uses the fifth-generation hybrid technology.

AM: Most Toyota hybrids get the CVT transmission, not torque converters. Why is that?

HM: Considering the fuel economy. So hybrid-electric and engine control is very sensitive and complicated and the CVT gearbox makes switching between both of them seamless. So that is the main reason we use CVT and also it gives good fuel economy. 

AM: The switch from rear-wheel drive to front wheel drive. Was that because of the platform?

HM: Yes. From the customer's point of view, the Innova is used mostly as a chauffeur-driven car. Also, many people drive FWD cars because one of the strong points of FWD is the packaging performance and fear economy because the friction is very low. So we choose front wheel drive.

AM: How long has this Innova been in development?

HM: Honestly saying it has been in development for almost five years. We studied the Indian market and Innova along the way and we spent almost one year on basic planning for this vehicle.

AM: Now the Toyota Innova is going to be sold in many markets. So how do you engineer one product for multiple needs and multiple markets?

HM: Toyota has many cars such as Prius, Camry and so on but India and Indonesia are big markets for Innova and we have very good relations with each country. Sometimes they come to Japan to test drive it together and we hear their opinion and improve and implement it. 

AM: One thing that you spoke about a lot was the packaging. So apart from the monocoque what have you done inside the car to form a better-packaged car?

HM: One point is making the car roomier for the second and third rows. Especially the third row’s seating posture is not so good in the current Innova so we tried to improve it along with making the second row more comfortable. So we added an electrically adjustable seat for the second row as well as a big sunroof for the second-row seats.

AM: What have you done for the third row to make it more comfortable?

HM: This platform uses the flat floor design which is also used in Japan in Voxy minivan. The Voxy in Japan and the one in India use the same platform. They are sister cars. The strong point of this platform is the third-row floor which is lower than other vehicles. So the distance between the heel and hips is increased. So the seating posture is much better and more comfortable. The design of the quarter window size was a challenging part because from the exterior the styling is very important but from the interior point of view, the lumination is very important.