Meet the Mini Mirai, the UK’s first hydrogen-fuelled remote-controlled (RC) car, based on the hydrogen-powered Toyota Mirai bigger brother. But why, and more importantly, how, you might ask?

Before we answer those questions for you, take a look for yourself at our Mini Mirai in action as we went for a spin around Old New Inn Model Village in Bourton-on-the-Water, Gloucestershire. Could there be a more appropriate setting to showcase this UK first?

Why miniaturise the Mirai?

Being at the forefront of hydrogen technology, Toyota wanted to showcase the potential for hydrogen to be used in multiple, slightly more novel ways. Toyota has already made a name for itself in terms of hydrogen power, with more than 20 years of hydrogen research and development which led to the launch of its first production fuel-cell car in 2015, the first generation Mirai. Continuing to pioneer fuel cell technology and following this year’s launch of the all-new Mirai, Toyota is increasing its fuel cell production ten-fold to 30,000 units a year. This will enable the expansion of fuel cell technology into broader forms of transport and haulage, as well as industrial energy applications.

How did we create it?

In order to create our one-off Mini Mirai, we enlisted help from Bramble Energy, a company specialising in miniature hydrogen applications, and the Tamiya model company. For the body, Tamiya used their expertise to create a 1/10 scale replica of the new Mirai hydrogen saloon with one of Tamiya’s popular TT-02 RC cars used as the starting point. In order to achieve a striking resemblance to the full-sized Mirai saloon, every inch of the vehicle was surveyed, with even the colour of the Mini Mirai (Scarlet Flare) being an exact replica of the real car.

For the hydrogen fuel cell system, Bramble Energy fitted a miniaturised version of its printed circuit board fuel cell (PCBFC) system, a control system and hydrogen storage, into the standard four-wheel drive RC chassis – the exact same one that is readily available in model shops before the Tamiya Mirai body shell was fitted on top. The Mini Mirai is fitted with two hydrogen fuel canisters that are switchable, allowing for quick replacement when fuel runs out. The Bramble Energy system provides around 20 Watts of power, with double the running time capacity compared to a conventional battery-powered RC car.

Just like its full-size sibling, the RC model excels when it comes to driving range. The new Mirai can cover up to 400 miles on a tank of hydrogen. The Mini Mirai can cover twice the distance of an equivalent, conventional battery-powered RC car.

Source: Toyota UK

The Tamtech-Gear Grasshopper Mini is a pre-built R/C car packed with high performance mechanisms in A4 size. This time we will introduce optional parts that will dramatically increase the driving performance.
Products featured in the video:
RC Tamtech-Gear Grasshopper Mini (GB-01S Chassis)
00:46 OP.2017 Tum Tech Gear GB-01S 2.6x29mm Aluminum Turnbuckle Shafts (Blue, 6pcs)
01:35 OP.2011 Tamtech-Gear GB-01S CVA Damper Set (4pcs)
02:25 OP.2012 Tum Tech Gear GB-01S Setting Spring Set
02:38 OP.1860 370 Sport Tuning Motor for T3-01
02:58 Tamiya LF1100-6.6V Racing Pack (M)
03:03 Tamiya LF-6.6V Battery AC Charger
03:15 OP.2010 Tamtech Gear GB-01S Full Bearing Set

I tried to make it like a factory tour how the comical Celica body made by Otsukai Chaly was made.
This time, the VR character (self-made avatar) Suzu-chan explains.
Large Celica is vacuum formed by making a wooden pattern from 3D CAD.
It is a full scratch build body (self-made body).
Dedicated mirrors, grilles and hubcaps are made of elaborate chemical wood.
Source: おつかいchaly

Click on the link to watch the build video in YouTube.

This is a time lapse build of a custom Tamiya Super Storm Dragon adapted into a Lancia Stratos Rally buggy concept. At the end of the video I show the complete results. Of the Tamiya Grasshopper chassis, the Super Storm Dragon (SSD) body in it’s box art form is my least favorite—but I’m sure it’s relevant and admirable to fans of the ‘80s Japanese manga/anime RC series where the Storm Dragon originated from. I also feel the body is too long for the chassis but perhaps that was the intent. It’s probably supposed to represent a slender mythological Eastern Asian dragon but all I can see is Falkor from the Neverending Story. However, I do like the greenhouse (windshield). Whenever I see it one thing comes to mind—the Lancia Stratos HF from the 1970s.

I wonder if the illustrators of the SSD got inspiration from the Stratos, if they did I wouldn’t be surprised. The Italian Stratos came out in the ‘70s and was purely developed and designed for the World Rally Championship. Designed at Bertone by Marcello Gandini (he also did the Lamborghini Miura and Countach, Ferrari Dino 308 GT4, and De Tomaso Pantera to name a few). Timeline wise, the SSD came out in the early ‘80s and that Stratos’ greenhouse was already an iconic thing. I always thought if an SSD fell on my lap I would frankenstein it into a buggy version of the Stratos. And so over a year ago I came across an SSD on sale for about $86 USD and I couldn’t pass it up.

I didn’t want to slap stickers and call it a day. I wanted to at least have a little effort in translating it. The SSD body was trimmed and shortened (the Stratos has a relatively short body/wheelbase). I wanted to stay within the rally Stratos color palette and that also meant a careful selection of the parts and electronics color.

Since I don’t have any off-road track in my area I knew this would run on tarmac or very abrasive surfaces. I installed a Tamiya Super Stock RZ (on-road 23T, 27k RPM) and at least had to upgrade the stock rear dampers with big bore ones (plus 500 damper oil and hard springs) and compress the front springs for a stiffer ride. The rear suspension axle mount was replaced with an aluminum one that can accommodate the beefier dampers. In addition, a longer 8mm T4 Works rear billet aluminum hanger was added with a makeshift mount/brace to lock the rear suspension in place—just like the Grasshopper’s. I feel the Grasshopper performs better on flat surfaces vs the Hornet due to the rear suspension design—the SSD has the Hornet’s. The front arms and suspension brace were upgraded to aluminum, the servo saver/steering rod was replaced with T4works aluminum servo saver and steel turnbuckles. Of course the plastic bushings were all replaced with metal ball bearings. The result is very apparent when running it. It’s quite stable, runs straight and fast, and the suspension just right (not as bouncy). A few caveats: because the front suspension is set very low and the aluminum arms/knuckles are not adjustable, it has more negative camber than I would like. That would probably be an area I would fine tune in the future. The aluminum arms creates some rattling noise as it doesn’t have a snug fit. I think adding rubber sleeves on the connection points to the chassis might solve it. To further improve handling, I need to replace the tires (didn’t have the right ones when I did a test run). And for the first time I tried a Dynamite ESC and I think it’s a tad glitchy. With some more fine tuning work, this setup can be quite a serious basher.

All this work and parts are not to just add bling. I genuinely wanted to find out what the potential of this iconic beginner chassis is. Ironically, I think it’s not worth it if you just want a simple basher (at least on tarmac/flat surfaces). If you’re going to “casually” run this on flat hard surfaces, I wouldn’t bother with this Hornet/Storm Dragon chassis. I highly recommend going a step down and getting a Grasshopper instead. I’ve built a Grasshopper for someone and tried a variety of motors in it (380, Sport Tuned 380, 540 silver can, and Torque Tuned 540) and once we got to the Torque Tuned motor, it was lively, fun, just right, and relatively precise. In fact, I love how the Torque Tuned Grasshopper drives that I can’t wait to drive it again. However, this Stratos Dragon evolution definitely has more potential.

Parts:
Tamiya Super Stock RZ Motor
KO Propo KR-212FHG receiver
Dynamite DYNS2210 ESC
AGFRC B44LS low profile servo
Metal ball bearings
Robinson Racing steel pinion gear
T4 Works: aluminum servo saver, steel turnbuckles, aluminum motor mount, 8mm billet aluminum hanger, aluminum wheel star disk
YR Big Bore rear dampers
Generic rear aluminum suspension mount
Avante front bumper
M&M rear bumper
Associated rear wheels
Schumacher rear tires
You-G Japan front tires
Tamiya Black DT02 front and rear wheels
Tamiya DT02 front tires
Tamiya Dual Block rear tires
Tamiya rear hex adapter
GPM alloy parts (front arms and brace)
Custom decals

Source: Mechanic After Hours