Iwata Asks is a series of interviews conducted by former Nintendo Global President Satoru Iwata with key creators behind the making of Nintendo games and hardware.





Iwata Asks: Wii MotionPlus

East To Hold With Both Hands

Iwata

So while you were engaged in a bitter struggle with the gyro sensor, tell me how you decided on the shape that the Wii MotionPlus accessory would take.

Wakitani

At the start of the development process, it looked like this.

Iwata

It's very different from the design of the finished product.

Wakitani

The first thing we thought of was naturally how comfortable it would be to hold. That was why we chose to make it as compact as possible. But in the end, to prevent possibility of the Wii Remote slipping when they are waving it energetically, we slightly expanded the bottom to give it a kind of skirt shape. On top of that, we have combined the Wii MotionPlus within the Wii MotionPlus Jacket to enhance safety.

Iwata

The idea of combining them to ensure safe usage was something that came about after E3, wasn't it?

Wakitani

That's right. But the prototype we put together at that point had a skirt shape with a very gentle curve, meaning that it could become detached very easily.

Takamoto

And from the point of view of maintenance and repairs, we were unable to use any adhesive to secure it.

Wakitani

That's why we made the skirt wider so it was a kind of flange shape such as you would get when fitting a car tire to a wheel. That's how the final shape ended up like this.

Iwata

You really did combine it very snugly with the Wii MotionPlus Jacket, didn't you? (laughs)

Takamoto

By making the skirt wider, you are able to grip on to it tighter, even when you swing the remote strongly. This was a very important consideration.

Wakitani

It's a little like the grip end of a baseball bat.

Iwata

That makes sense. And out of interest, what do you make of the fact that the length of the Wii Remote has increased?

Takamoto

Well, it has made it very comfortable to grip with both hands.

Wakitani

I think that games where you hold the Wii Remote with two hands, such as golf and baseball, have become a great deal easier to play.

Ito

Though with the original Wii Remote, there seems to have been players who swung the bat using only one hand! (laughs)

Takamoto

That's why we thought we could have afforded to make it even longer! (laughs)

All

(laughter)

Iwata

So while the electronic engineering team was doing battle with the gyro sensor, the mechanism design team also had some awkward problems to contend with.

Takamoto

Yes, you could say that! (laughs) Since we're on the subject of connecting the accessory, the bottom of the Wii Remote has an external extension connector for connecting the Nunchuk and other accessories. On either side, all you have are holes.

Iwata

Yes, there are two holes to lock accessories to the Wii Remote.

Takamoto

So we thought about using these two holes and tried to secure the Wii MotionPlus accessory using hooks. But those holes were not originally designed with the purpose of connecting Wii MotionPlus in mind. They were actually designed for a separate purpose, which was attaching accessories in a less secure way.

Iwata

So the designers hadn't envisaged something like Wii MotionPlus which would be attached firmly to the Wii Remote.

Takamoto

Moreover, they hadn't envisaged that the area where the devices were connected would be gripped tightly and shaken repeatedly.

Wakitani

That's why we had cases where there would be temporary disconnection of Wii MotionPlus during use.

Iwata

So the accessory would disconnect from the Wii Remote just for a brief instant?

Wakitani

That's right. So at that point we looked to investigate further by trying to reproduce this temporary disconnection by twisting and turning the Wii MotionPlus accessory. But it wasn't something we could do by only twisting it slightly.

Takamoto

Without shaking the Wii Remote tens of thousands of times, this temporary disconnection wouldn't reoccur.

Iwata

But you weren't really going to shake it thousands of times to test this, were you? (laughs)

Takamoto

Well, at the start I gave it a go, but after a while my hand got so weary that I had a hard time holding it.

Wakitani

And that's when the gloves went on.

Iwata

You really went that far? (laughs)

Wakitani

But doing it that way would have been far too time-consuming. So it was at that point that we decided to borrow storefront display models for Pokémotion4. (laughter)

4. Released by the Pokémon Company in Japan in August 2003, Pokémotion was a
“communication tool” shaped like a glow stick. By utilising flashing LEDs, it left images
on the eye allowing users to see various Pokémon and words when it was waved rapidly.

Takamoto

That's the shore display where the Pokémotion is swung like a metronome.

Iwata

Ah yes, I remember that.

Wakitani

We scraped together all the models we could, from our Okayama office and various departments within the company, and then used them to carry out tests.

Iwata

It's lucky there were still so many left! (laughs)

Wakitani

The conclusion we came to was that the plug for Wii MotionPlus was attached completely rigidly to the connector on the Wii Remote.

Iwata

So it was attached very firmly with no room for give.

Wakitani

Right. Which is why after waving it repeatedly, it inevitably placed a strain on the connector.

Takamoto

If you were to connect it to any normal peripheral it wouldn't be a problem, but in the case of the Wii Remote, because it's a product where you actually grip the connector and wave it repeatedly, it was impossible to avoid a heavy strain being put on it.

Iwata

Which is why this temporary disconnection occurred.

Wakitani

We experimented with a variety of possible solutions, such as putting oil around the connector or leaving a small gap open but…

Iwata

But you kept hitting dead ends.

Wakitani

Yes we did. So we experimented with redesigning the Wii MotionPlus connector plug so it fit more loosely into the connector as a way of avoiding placing strain on the connection.

Iwata

So it was a bit like fitting the plug with suspension.

Wakitani

The technical term is a "floating structure". We used the trial equipment to carry out tests on that structure and the rate of temporary disconnection declined dramatically. So we felt we were on the way to solving the contact problem. But then, just at that point…

Iwata

What happened at that point?

Wakitani

The connection hooks used to lock Wii MotionPlus into the holes at the base of the Wii Remote snapped.

Iwata

I see… Up to that point, the accessory had been connected in three places: by the plug and the two hooks. But once you'd redesigned the plug so that it was a floating structure, too much strain ended up being placed on the two hooks.

Wakitani

That's exactly it. So we thought there was no solution except to reinforce the strength of the hooks.

Ito

That's why we used steel hooks.

Iwata

Steel hooks?

Wakitani

But we went a bit over the top in reinforcing the hooks' strength...

Takamoto

...And this time the holes in the Wii Remote broke!

All

(laughter)

Iwata

So even those steel hooks didn't end up working out for you! (laughs)

Takamoto

It was at that point that someone suggested adding a tray-shaped section on the reverse side to integrate the Wii MotionPlus accessory and the Wii Remote more fully…

Iwata

It sounds like a splint for a broken bone! (laughs) But by doing that, wouldn't you make it more difficult to hold?

Takamoto

Yes, it becomes too bulky.

Iwata

So how did you finally resolve this one?

Wakitani

We decided to use a type of plastic which was very durable and could withstand the repeated strain.