Investigación y Desarrollo, No hay decisiones aleatorias.

Cuando diseñamos originalmente El Carro (THECar), la idea fue crear algo completamente nuevo y diferente, algo que pudiera convertirse en el mejor carro del mundo. Tuvimos éxito parcialmente en eso, pero estuvimos fuera del rango de lo que puede llamarse, universalmente el mejor carro del mundo.  Me enfocaré en manejar ésta historia, porque respecto a calidad y durabilidad, casi ningún carro está cerca al nuestro, porque casi todos están hechos en las mismas fábricas, y eso no es interesante para nuestra historia.

car

Creemos que El Carro(TheCar) es el más rápido y el mejor para un cierto grupo de pilotos.  La definición más generalizada que puedo hacer, es que pilotos que son entre 1-4 segundos de los mejores tiempos por vuelta son los mejores del mundo, y tienen un estilo de manejo en calma y controlado. Esto es confirmado por un sinnúmero de correos electrónicos, mensajes de Facebook y otras vías de comunicación que recibimos de clientes felices que “instantáneamente fueron 1 segundo más rápidos al cambiar de marca X a JQracing”, ¡en algunos casos incluso más rápidos! .  Al principio pensé que era sólo de los fans que hacían la barba, pero llegué a la conclusión, que realmente había verdad en esas exclamaciones.

La manera que diseñamos El Carro fue extrema, tenía brazos cortos, muchísimo offset en la parte trasera, distribución muy delgada del peso, una geometría de dirección agresiva, era ligero, con incluso muy ligero engranaje y tren motriz comparado con la competencia, tenía un engranaje agresivo, todas esas cosas hacían de El carro un manejo responsivo y rápido. Queríamos hacer un carro muy rápido, y lo hicimos, pero nos olvidamos de un factor muy importante. ¡Encontrar alguien debía ser capaz de manejarlo rápido!.  Hay límites con la velocidad y los reflejos del humano, y en este tenor, para un carro que era rápido, sobre todo en un periodo largo de tiempo y variaciones en la pista, tenía que ser sencillo de manejar. También necesitaba responder en situaciones de manera controlada, no llegar a un punto límite de tracción, dirección y roll, y de pronto hacer algo sorpresivo.

 

limit

¿El límite fue alcanzado?

Esto explica porqué El Carro (THECar) es tan grande para un cierto tipo de pilotos. Ellos lo manejan calmado, y aun así El Carro hace todo muy rápido, acelera rápido, mantiene la velocidad de curva, cambia rápido de dirección, es rápido. Pero ellos son lo suficientemente lentos como pilotos, donde la velocidad de las cosas que ocurren en la pista no necesariamente significa que ellos no pueden mantener la calma, y no presionan al Carro al punto donde hace algo inesperado.  Trata de igualar la velocidad de los mejores pilotos del mundo con esto y no se ve tan bueno al final de cuentas.

El Futuro no es Copiar, pero si entender

El próximo paso era obviamente desarrollar El carro (THECar), a donde pudiera ser rápido de manera natural, pero al mismo tiempo fácil de manejar y controlable a velocidades extremas, manteniéndose estable. La pregunta es, ¿cómo lograríamos eso?

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Mucho estudio, rascarse la cabeza, utilización del ordenador y CAD, pruebas en la pista para entender qué sucede.

La premisa más popular en torno al desarrollo de un buggy parece ser “Simplemente copia a Kyosho” o “simplemente copia el Mugen”.  Esos dos parecen ser los estándares para todos los que tienen falta de imaginación y quieren salir con una copia “ya ya ahora” . Por supuesto que no tiene caso re inventar la rueda, y por supuesto que tomar los conceptos de la competencia y mejorarlos para ponerlos en un diseño propio es un buen trabajo. Sería irrisorio no hacerlo, ellos obviamente han trabajado por muchos años y probaron muchas opciones diferentes, pero ¡también pueden estar equivocados! .  Como sea, hay una falla fundamental en “sólo copiar a la marca X”. Copiar salta la parte del entendimiento.  Si en este momento sólo copio exactamente la geometría de otro carro y encuentro que hay una mejoría en lo que tengo actualmente, entonces ¿podré mejorar más delante? ¿debo esperar de nuevo a que la marca X salga con un nuevo modelo para copiarlo de nueva cuenta?  ¿sólo adivino? Si uno está mejorando constantemente, uno debe saber y conocer porqué el diseño es de una manera, y cómo llegué a este punto. Todo esto es importante si quieres convertirte en el mejor, y es también lo que más disfruto. Descifrar las cosas, y ver el resultado real en la pista de carreras.

 

Aprendiendo a entender al Carro (TheCar)

Para comenzar, necesitábamos entender por completo nuestro propio Carro. El entendimiento por completo lo alcanzamos durante el 2010-2012. Nos las arreglamos para saber los pros y contras de El Carro, y las razones  para las variaciones en el manejo que tuvimos. Pronto nos dimos cuenta, que para mejorar notablemente El carro, se necesitaba un mayor re diseño. Escogimos un camino extremo al inicio para algunas partes de la geometría, que pensábamos, y no encajaban con nuestra nueva visión de cómo un carro debía funcionar. Cualquier cambio que hacíamos, las características básicas indeseables estaban presentes, debido a la geometría intrínseca. Cualquier cambio en el diseño actual era sólo un curita.

track

Para aprender los ajustes, y para aprender sobre el manejo del Carro, necesitas tener una pista consistente y técnica donde puedas correr diariamente. Después de pasar tiempo suficiente en la pista debes sentirte gusto con lo que puedes hacer y la consistencia en las vueltas, y también puedas notar cambios pequeños, tanto en el manejo como en la mejoría de tiempo de cada vuelta. Esa es la mejor manera de hacer cambios significativos, de aprender nuevas cosas y desarrollar nuevas ideas.

Algunas de las cosas que descubrimos fueron que tener brazos cortos hacen el carro rápido, pero también hacen imposible de mantener los centros de rotación (roll centers) en un mismo sitio. Tener un centro de rotación que se mueve mucho, sobre todo si el frente y la parte trasera se mueven distinto, desajusta el carro. Es por eso que  puedes encontrar el mejor trazo para una pista sobre todo si el frente y la parte trasera se mueven en conjunto y de manera predecible, pero cuando vas a otra pista con un nivel diferente de tracción, los centros de rotación pueden ser mayores, y de nuevo se mueven causando efectos indeseables. Agrega a la ecuación el problema de los cambios en el camber por el roce de las ruedas que se vuelven más problemáticos con los brazos cortos y tienes la receta para un dolor de cabeza. Por roce de las ruedas me refiero en cómo se mueven lateralmente cuando la suspensión se comprime, en nuestro caso las ruedas se mueven hacia adentro cuando se comprime la suspensión.  Respecto a nuestro problema del cambio en el camber era mayormente en el offset grande del tren trasero, en conjunción con los brazos cortos provocaba un camber positivo en extremo mientras cruzaba las curvas. Así que en conclusión,  para tener un carro absolutamente rápido, los brazos cortos eran la manera de lograrlo por la naturaleza responsiva en curvas rápidas, pero requería un ajuste perfecto y un piloto muy hábil. Un balance tenía que encontrarse.

 

learn

No hay atajos. Si quieres aprender, debes ponerte a trabajar, y tienes que hacerlo tu mismo.

Otra cosa que aprendimos, es lo referente a la distribución de peso de El Carro. Originalmente hicimos el carro tan delgado como era posible.  Creímos que lo haría lo más rápido posible, y de hecho estábamos correctos hasta cierto grado.  Pero de nuevo nos olvidamos que El carro no se maneja solo, alguien debe conducirlo. Un carro delgado es más responsivo, y también se desajusta debido a las imperfecciones del camino y la diferencia de tracción entre las ruedas derecha e izquierda. Por ejemplo al rozar un tubo de la pista, un carro delgado se vuelca más fácilmente que uno ancho, o al pasar por un bache con sólo un lado del carro provocará levantar las llantas opuestas más fácil. De nuevo un balance debía encontrarse. Mientras más ancho, más estable se vuelve el carro y menos ágil y responsivo.

Aprendiendo una mejor comprensión de los buggies 1:8 en General

También decidimos a arreglárnoslas al atacar el problema desde otra dirección. Debido que El Carro es super rápido, pero sólo un puñado pueden manejarlo de forma agresiva por pilotos de clase mundial, debíamos encontrar qué es lo que hace nuestro carro rápido, y qué es lo que hace nuestro carro manejable. Pero lo que no necesariamente pudimos encontrar es cómo hacerlo realmente estable. Sólo por darnos cuenta de la necesidad de montarle brazos (horquillas) más largos y un chassis más ancho, no necesariamente lo haría tan bueno como se necesitaba.

Con la finalidad de aprender más en un corto período, comenzamos por hacer un carro bueno malo. Pieza por pieza comenzamos a reemplazarla en nuestros carros de prueba con otra pieza. La gente tiende a ver la respuesta obvia. Ellos dicen, la razón por la que un carro es bueno, está en los amortiguadores, en el chassis, y eso es todo, siempre asumir lo que se dice por ahí, basados en lo que es visiblemente diferente, no basándose en los hechos. No estamos desacuerdo con este tipo de especulación, así que cambiamos los amortiguadores por otros, el chassis por otro, más piezas por otras hasta que entendimos lo que favorecía el manejo de cada carro. Posteriormente verificamos estos hallazgos probando esas cosas en El carro. Queríamos asegurarnos que esas piezas tenían el mismo efecto en nuestro Carro.

Mejorando nuestro propio diseño

car

In real car racing where they have actual data, engineers are able to look at raw data and try to understand what is going on. They base their decisions on data, yet still a lot of vehicle dynamics and car development is considered a black art. There is just so much going on, so many variables, and no single correct answer. Consider that in RC racing we don’t even have the data! We are in the dark. We can look at pictures, slow motion videos, and CAD drawings, but we are still guesstimating and figuring things out by iteration. The one thing we do have that is better than in the ”real world”, is we can test things a lot easier and faster, roll centers, toe angles and steering geometry can all be changed in a matter of minutes.

Undeterred by this lack of information, and complexity of designing an RC racing buggy, we decided to really try to understand how to improve on the current car designs. We also spent a lot of time analysing the reasons for cars either flipping over, or losing traction and becoming out of shape. We shot a lot of video of different cars in different types of corners, and sections of the track, analysing how the chassis moves and behaves in these conditions. We were then able to watch the footage in slow motion, determining how much the chassis moves up and down, chassis lean angles, and camber change amounts, in an attempt to better understand the actual problems that occur when a car is pushed to it’s limit.

rc

What’s really going on?

We then constructed models of cars on the computer, where we could analyse various front and rear end geometries, studying the movement of the roll centre during similar situations that we had seen in our videos. By doing this for over a years time, on many different tracks, we were able to form an understanding of what is happening in both theory, and practice when a car negotiates a corner. Using the computer models, we were able to simulate setups that worked in the ways we wanted them to in theory. We then made prototypes that we were able to test on the track. I will never forget the first time that I came up with a setup on the computer, that worked almost perfectly on the track. It was a revelationary experience!

We kept doing this kind of testing throughout 2012 and early 2013, and finally we had figured out the following:

1. There are some basic principles that you have to have right, if you want to have a car handle in a certain way. Meaning that, for example, it is impossible for you to make your Losi handle like the Mugen because of the radically different front end geometry, and weight distribution, and vice versa.

2. You can have all the best ideas on a car and it can still suck. A great race car is not necessarily the best at even one single thing. It may not have the best acceleration, the most steering, it might not jump the best. Designing a race car is all about compromises, it needs to be balanced. If you have the most steering but the steering makes the car loose and the rear end unpredictable when exiting corners, what is the point of having all that steering? Balance is key, out of all the ideas and possibilities, they all have to fit and work together. This is the single biggest thing that people miss, when telling us: ”You should do it this way!”.

details

Details, details. Everything in this picture is there, and in an exact position for a reason.

3. It’s all in the details. After figuring out the basic principles of the car, that will define it’s main character, it truly is all in the details. A car will only perform really well, when everything on it is in the right place. Weight distribution, centre of gravity, roll centers, arm and link lengths, arm pivot points, steering geometry etc. Imagine every single measurement on the car, and imagine them all being within 0.5mm of what could be said to be ”The perfect car using these basic principles”. This is why the established cars on the market are so successful. Those companies chose their own basic principles back in the day. After that, they started developing their cars around these basic principles, and they have now reached a stage where all these measurements on their cars are within a very small margin, where the car is balanced and works well everywhere. The key is to find this balance. There is of course not only one correct measurement for each part, when using a set of basic principles of design. Every single measurment can be different, they just all need to work right together, and if this is the case, the car will perform.

What we set out to do, is first determine the basic principles that we thought constitutes a great car, front and rear end geometry style, drivetrain layout, and weight distribution, and then we started finding our balance. We wanted to reach a result where we had a naturally fast car with a lot of acceleration, mechanical grip and cornerspeed, and an easy stable nature. Easier said than done of course.

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THEWhite Edition Features

If we look at 1:8th scale buggies today, from the broadest perspective, they are all the same, they have the engine to the rear left, fueltank in front of that, electronics to the right, 4 wheel shaft drive, 3 differentials in similar locations, and independent A-arm suspension. In this sense they are all the same.

base

If we look closer, we can see that there are 3 different platforms that have emerged, divided by their geometry, mainly front end geometry, because it is so dominant in determining a car’s handling. In the past these groups were also separated by weight distribution, and other geometrical parameters, but lately they have become mixed, with new car brands using various combinations of geometries and weight distributions in their cars. But one separating factor remains, the front end geometry.

front

Group 1: The front end geometry, with a shorter front arm, high attachement to the C hub, mostly accompanied by centralised weight distribution, and a weight far forward design. This was the style of our first car, and the style of for example Losi, Agama and Durango, and also Xray and Serpent as far as the geometry is concerned.

pbs

Group 2: Then there is the pillow ball geometry, with pillow balls up front, often with laydown shocks, and slightly wider chassis layout. This is the style of for example Mugen, Sworkz and Radiosistemi.

front

Group 3: And finally there is the geometry with long arms, C hub front end, and average shock geometry, not lay down, not stood up, wider weight distribution, and a less extreme design in many ways. This is the style of for example Kyosho, Associated and Hot Bodies, and now the JQ Products White Edition.

These three basic styles have been around for a long time, and will probably remain the three main design solutions for the forseeable future.

What we realised with our first car, is that these three groups have certain traits, that cannot be changed, without changing the fundamental geometrical designs. All the cars in a certain group, regardless of weight distribution, shock positions, steering systems or arm pivot widths have certain handling characteristics that will always remain. What we learned is that cars in group 1 and 2, tend to have certain conditions where they excel, and others where they struggle. So one type of track or driver will be a perfect fit, while on another track or with another driver the car may not work as well.

track

All tracks are different. The goal is to build a car that works great on all of them!

This was not the case for group 3, and that is the reason for us choosing it for THEWhite Edition. This group is all about compromise. It is not clearly the best at anything, but it also does not struggle with anything. It’s advantage would lie on a track that has a bit of everything. A difficult track, with both fast and slow sections, both jumps and smooth sections, and varying traction levels. Here these cars shine, because of their consistency. This is the group we chose for THEWhite Edition, because we felt this style of geometry had the most potential. There were no problems to have to work around, just a possibility of working to improve every aspect of the car, and this is why we felt that choosing this direction, would make it possible for us to make a car that would always be competitive, regardless of the conditions.

This fundamental change to the design of our car, has enabled us to take a huge step forward, and has provided us with a greater range of possibilities for future improvements. THEWhite Edition is a serious contender at any level, and we are constantly working hard together with all our drivers, to improve it even further.

THEWhite Edition in Detail

car

One of the main features of the new car is the new longer suspension arms, which along with the new front end geometry, make the car a lot more calm and stable by nature. It keeps it’s line when cornering with less effort, and does not become unsettled by bumps and ruts. It also lands a lot better and feels more plush and smooth on the track.

arms

The new geometry, together with the wide weight distribution, and updated steering geometry, make it possible for the driver to drive precisely with far less precise, and more calm steering input. A driver is now able to turn the wheel more, and do so more calmly, resulting in an easier car to drive. On the track the car still has a lot of steering, and it is possible to place it exactly where desired, but to do so is a lot easier, and requires much less precision and speed.

gear1

We also worked a lot with improving the throttle control, traction and feel of the car. The new gearing ensures that the car accelerates smoothly, maintaining traction. Again it requires less precision from the driver, as the car does not respond as aggressively to throttle input, yet it still accelerates fast, due to the more consistent traction.

shocks

The shock absorbers have been improved, and also enlarged to the now, almost industry standard 16mm size. The rear units have also been lengthened due to the change in suspension geometry. On the new car, the piston speeds are higher, and as such the shock absorber works differently. We realised that a larger shock absorber would be better, and decided to go with the most popular size, simply because having the same piston size as most others, could potentially be beneficial for finding more working setups, and we already know 16mm performs well.

shocks1

The rear end geometry now incorporates a set up option running a short arm, with more rear offset, or a long arm, with less offset. When designing the original car, we had to decide to either use this system, or the vertical holes in the arm. At the time we made the wrong decision and chose the vertical holes. Having the option of changing the length of the rear arm, along with rear offset is more beneficial in our opinion. The overall track width stays the same with both setups. Running the rear arm short, increases steering and forward bite, and helps the car square up better exiting corners. The car is noticably faster in hairpins. But the downside is that the car can feel too nervous for some drivers. Running the rear arm long, increases stability and rear traction, and reduces steering. Both set ups can be as fast, it really comes down to driver preferance.

rear

Can you find the mistake in this picture? I hope so! The insert is in the wrong way round. + to the inside for toe in!

The rear hub uses plastic inserts to set the height of the hingepin, with 5 possible locations, each separated by 1mm. It is also possible to add outboard toe in, with 0.5 and 1 degree toe in inserts available. This increases rear traction and stability dramatically! It will be completely impossible for anyone to complain about lack of rear traction, with our new car.

gear

The car includes CNC aluminium front C hubs, steering knuckles, and rear hubs which improve the rigidity and the durability, increasing the value of the car out of the box. We have focused on all the smallest details, with improved shock mounting hardware, hingepins, and an updated CNC centre diff mount.

hinge

Improved outer hingepins, with 2.5mm hex, and smoother, more durable finish.

Setup Options

We feel that with the introduction of THEWhite Edition, and with our new understanding of car design, and the link between theory and practice, we have now reached a point where we are attempting to find a balance, and an edge on the competition. What we wanted to achieve with this car, is a design where it is good everywhere, with no obvious weaknesses. We believe the choices we made has made the car one that will perform well on any track, and in any conditions, with the basic set up, regardless of the driving style the driver has. We did not try to make the car very specialised, and perfect at one thing, in a way that would make it struggle in another area. But what we did do, is make the car adjustable enough, in the ways we felt was needed, to make it possible to set it up to suit any specific track condition or driver as perfectly as possible.

options

Yes there are options, but they are there for a reason, and we teach you how to use them.

For this reason, we still have a lot of set up options available on THECar. Tuning a racing car is an art form, and every driver is different. We believe that we have included the tuning options needed, for anyone to be able to tune the car to their liking. As we further develop the car, we expect the tuning options to be both reduced and refined, but for now, we will provide you with guides for how we like to use the available options, so you don’t get lost. And in case you do not like to experiment, no need to worry, we have come up with a number of basic setups, to suit different tracks, and different drivers.

Conclusion

We realised that when designing a racing car, it is not only about how fast the car is, how much steering it has, or how much acceleration it has, but more about controllability and handling. We learned that we need to place more emphasis on the driver, and the experience of driving the car. The car should feel like it wants to be driven, and it should inspire confidence in the driver. Afterall we all race because we enjoy it, and we all want to win, so our goal is to make driving at your maximum pace, as much of an enjoyable experience as possible.

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