Daniel-99

Eurobricks Vassals
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About Daniel-99

  • Birthday 11/01/1999

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    ferrari 488 gte 42125

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    Lego technic RC

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    Russia

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  1. Hello everyone! I would like to introduce you my new top-tech mid-scale Trophy Truck "Falcon". This car is a TRUE RC car in Lego clothing. Technical characteristics Full independent suspension with positive caster on all wheels Minimalistic and strong transmission with metal CV-joints 4 - wheel drive 4 Buwizz motors for propulsion (1 motor per wheel) Custom RC controllers adapted for Lego 3S Li-Po 35C 2600 mAh for power GeekServo for steering soft RC wheels 75 mm Custom wheel hubs with metal bearings Light bodywork, 1270 gram of total mass Instructions? Some of you might be interested in instructions. Well, there will be non, I am sorry! Here I will explain why instructions for this car are impossible. Falcon has 4 Buwizz motors for power, which can be easily changed to Buggy motors or Mould King version. Power source and controllers could be replaced with two Buwizz 3.0 units (in theory). But there is no way to replicate both suspension and transmission with lego parts only. Non-Lego solutions: Custom 3D-printed parts, such as wheel hubs, steering arms, suspension arms with 4,5 stud length Modified Lego parts Hand-made parts from plastic bottle ;-) Broken Pythagorean theorem in suspension metal parts, which make the whole car rigid Chassis Falcon has same chassis as a Wilde beast, but with shorter wheel base and suspension arms. So I will not dive into details here. Bodywork I was inspired by a Trophy Truck by Keymaker`s armored Trophy Truck. Though I reduced some details and widen the body by two studs to fit the chassis. Made for outdoor driving This car is not a shelf model. It was made for regular, extensive and extreme driving. Recall, that the elder brother Wilde Beast had a problem with motors: they were not strong enough to translate all the power from Li-Po battery to 90 mm RC wheels. That is why Falcon was made in a smaller scale to fit 75 mm wheels. Now motors does not struggle at all! Enjoy drifting on sandy road? - easilly! Lego Outdoor cars usually struggle from dust and dirt filling the transmission. This car has a minimalistic transmission without Differential, so there is noting to break. The weakest parts of lego cars (wheel hubs with CV joints) have been replaced with custom hubs with metal bearings - no more plastic dust in transmission! And nothing to brake! Massive 3S Li-Po provide an hour-long continuous driving. RC controller with physical buttons is very comfortable to use. After two weeks of tests I added fenders for the front wheels to keep the inside of the car from being filled with stones. 4WD drifting is a fun thing to play with, but I got tired from cleaning the car from small stones after each driving session!
  2. The video quality is great, the road has a challenging surface, which is also good. Though the car is a bit too slow, even for trial truck (it is worth doubling the speed in the future trial models). Also I noticed that the truck does not have a "continuous" motion: it is moving by periodic micro-steps... I guess that might be caused by the transmission or lack of power of the motor (to find the problem, it is worth trying to power your truck with a Buwizz 3.0 unit cause it will give more power to the driving motor).
  3. Thank you all! I spent a lot of efforts in the chassis and I am glad you liked it. The body is definitely a bit flattened ;-) I tried my best to build a body over the flat chassis, but there is much to improve.
  4. Hello everyone! I am glad to introduce you my new Lego MOC. It is called "Wilde Beast" and it is a 1:10 scale 4-wheel drive pickup truck. Technical characteristics 1:10 scale, 1.630 kg of total weight All wheel drive with 4 x Buwizz motors powering each wheel separately 2 x Geek servo for steering 3S Li-Po for power RC radio + Wixy units for control Full independent suspension with customizable hardness Custom wheel hubs with metal bearings RC wheels 90 mm (12 mm hexes) Metal U-joints in the transmission Robust 3D-printed steering bones Positive caster angle on all wheels Back to the beginning The main Idea behind the build was inspired by real e-cars. This cars has no gearbox, and each wheel gets connected to an e-motor independently. I tried to replicate this principle with Lego bricks and some custom parts. Bodywork This car has is a 1:10 scale pick-up truck body, Though it is a bit too short for a normal pickup. The body was made to be light and it is build on the chassis with a half-stud off-set in order to make the wheels seating symmetrically in wheel arches. (It was an obligatory decision due to the positive caster angle). There are many things that can be improved in the bodywork, but the current one perfectly satisfy my needs: it is light but make the car somewhat recognizable as a car. Hope to find white fenders to the front wheels some time! All the driving elements are located in the lower 5 studs of the car, so it is very stable. Suspension Wilde Beast has a full independent suspension with positive caster, which is very unusual for pickups. Moreover it was made to be customizable for different purposes. 9L shocks connected to the lower bones of the suspension play main role. At the same time upper bones of the suspension has their own set of shocks which can be customizable! Custom wheel hubs provide a natural King-Pin Inclination. Transmission "A good transmission - is no transmission"... This was my main philosophy for this car. The car has 4x Buwizz motors for propulsion, each motor is connected to one wheel of the car via half-axle (which uses metal U-joints). "Gear Ratio": Slow output of Buwizz motor -> 95 mm wheel. Such solution has its own positive and negative aspects. Positive: extremely low friction stiffness fast cornering (e-differentials) High maximal speed (over 13 km/h) Negative: Too big stress on motors (a smaller wheels would work well) Car does not go straight due to the difference in motors Let me explain the last "problem" in more details. The motors used in the car are "the" same from the view-point of a lego builder. Though they are "different" from the physical view point: each motor has individual characteristics, such as resistance, max power, max rotation speed and so on... This difference can not be seen in slow models (with max speed under 7 km/h) but they became critical at speeds over 10 km/h. As the result, car is always turning to one side and the driver need to correct the trajectory with a steering. There are only two ways to fix this problem: either to make a mechanical balancing via differentials, or to test each motor separately, and make individual power curve to it. A steering system with build-in hygroscope might also help. Controls The car is controlled via RC radio. The whole system is very similar to RC car setup. 3S Li-Po is used for power, it powers controllers for driving motors (called Wixy). The controllers provide the power to Buwizz motors by a signal of receiver. The model is steered with 2 x GeekSevo, though one would be enough here. To see a detailed description of the system, see here: Conclusion The Wilde Beast was a great research project for me. I tried to replicate a real e-car layout and my goal was achieved. Car is very fun to drive, but the driver needs to pay a careful attention to the road. The main problem of the car is the lack of the e-brains which would allow to calibrate the driving motors... P.S. I will definitely make another car with same chassis on smaller wheels to reduce the load on motors.
  5. I saw your brilliant trophy truck! Yes, brushless motors are on the next step in the hierarchy of electric motors, they provide such a torque an speed which can not be achieved with Buggy motors ;-). Currently I don`t have a brushless motors set-up for Lego, but I will look forward to get one!
  6. I wanted to build a fast car with "normal" hubs and 4 x Buwizz motors. Here are the first results. Currently it has 2 Buwizz motors on the front, but I will add two more motors to the rear at September. Specs: Buwizz motors for propulsion 3S Lipo for power RC control system independent suspension custom wheel hubs with metal bearings and metal U-joints positive caster on all wheels 95 mm RC wheels minimalistic transmission This is only the first draft of the chassis, the bodywork will be added later, and it will clearly increase the total weight. To deal with extra weight, I will install two more Buwizz motors. I will try not to exceed the limit of 1,7 kilos. Current chassis drive very smoothly. Thanks for the metal bearings and Buwizz motors which have a very low friction. It drives so smooth, that it requires the braking system! Such layout is very efficient, but does not allow to drive slow due to the specifications of motors. So such chassis wont be able to perform at trial or extremal off-road. It it applicable for fast driving at the rough terrain such as country roads. So the layout with 2 speed gearbox has it`s own benefits, though it can not be that efficient. Here is a short driving test:
  7. I see. The visible disadvantage of big gears is their size, though they are very neat gears in terms of transmission efficiency. Also it is worth noting, that raised suspension will cause more stress at the CV joints, especially an the front axle. Which hight you are trying to achieve with the ground clearance? My tests showed that the outdoor car needs at least 3 studs.
  8. Nice progress! Version 2 is way cooler then V1, and I appreciate the new transmission, though the bodywork can be slightly improved . What is the weight distribution of Version 2?
  9. Hello Eurobricks! Here is a Blue Mamba V2 - a wild mix of energy and rigidity. The story begins. Several months ago I build a fast off-roader for the King Of The Hammers competitions. The main idea behind that car was the minimalistic transmission. Well, there were now gears in the transmission, but there were CV-joints at the front axle and they were very weak! There was no way to fix that problem until one Russian AFOL comes with the custom wheel hubs with metal bearings and metal U-joints! These hubs allow to use a variety of RC wheels with 12 Hexes. Awesome! I purchased a set of custom hubs, and started the development of the Blue Mamba V2. Before diving into details I want to highlight another principal change in V2 project. V1 Mamba was powered by Buwizz 3.0 unit, but it drowned with my mid-scale trophy truck this spring. So for V2 Mamba I bought a custom Lego-compatible compatible RC controllers “Wixy” provided by another Russian AFOL. These controllers allowed me to use all benefits of GeekServo and Powerful 3S Lipo with 2600 mAh capacity. Bodywork. The car has a minimalistic bodywork. All panels used as structural elements. There is a plenty of space for the cockpit if one would sort all the wirings. The only decorative element is a fake V6 engine located behind the cockpit. Currently I have no PF motor available to make the engine work, but I keep in mind such possibility. Drivetrain. Blue Mamba V2 is a true E-vehicle with 4 PF L-motors powering each wheel independently without any transmission. Custom wheel hubs with metal bearings and metal U-joints make the transmission totally undestroyable. My goal was to minimize the width of the car. But the complexity of the front axle provided a lot of restrictions, so I had to widen front axle by 2 studs comparing to V1 Mamba. V1 Mamba has a steering motor located in the cockpit and linked to the front axle with new CV-joints. I replicated same configuration to the V2, but driving tests revealed big wobbling of the steering system, so I decided to place a GeekServo on the front axle (luckily it is very compact). A small regret is that GeekServo is not powerful enough for this wide and grippy RC wheels, It can not return them back if the car does not move. Likely, a positive caster angle of the front axle helps to back steering when car moves. Suspension. Mamba has 3-Link bridges at both axles with heavy-duty suspension arms. I had many attempts with the spring attachment. Finally, I understood that a responsive suspension requires a direct mounting of springs to the axles. 9.5 L shocks has very good springs (comparing to the soft 9.5 L one), but they were too hard for the car because all motors were placed on axles. An interesting idea came to my mind: why don`t you place these shocks diagonally? It works like a charm! Control. Car has a low center of gravity due to the placement of motors and 3S Lipo batteries. In addition, it has a proper wheel base and grippy tires, which makes the car very stable. Accuracy of GeekServo and RC transmitter provide a very smooth driving experience (though a stronger servo motor would improve the performance). Finally, 4WD helps to go through any terrain, such as sand, grass, etc… The top speed of the car is about 8.5 - 9 km/h. So it is very interesting to play with it outdoors and take it for a walk, since it has enough speed to drive back and forth while person walks. I tested this car with 120 mm RC wheels. The motors have enough power to handle and increased load while all the other plastic components (such as steering elements) were struggling a bit... On my opinion, 95-100 mm wheels are the optimal solution for fast outdoor cars. From one hand they provide a decent ground clearance and able to roll over the bumps. From the other hand they does not provide a lot of stress to the Lego parts. ' Conclusion. After multiple outdoor tests I conclude, that Blue Mamba V2 is the perfect Lego car, which is capable to go through any terrain with decent speed. It is strong and efficient and very controllable vehicle, which is pleasure to drive! Though It is too fast for trial. It is hard to go 2 km/h balancing between obstacles and barriers. But this is not a disadvantage, simply because each vehicle has it`s own areas of use. P.S. Speaking about Wixy Some of you wanted to know more about "Wixy" setup. So I placed all the component on the desk and marked them as follows: Wixy units RC receiver 3S Lipo PF motors Geek servo "Wixy" unit plays a role of an RC ESC unit, and it connects to the other electronic components in the same way: B-cable transmit the power from Li-Po batteries to the bottom PF connector (input) of Wixy units. A-cable feeds an RC receiver for Wixy units and translates the controlling signal at the opposite direction. Unusually for drive the "Channel 2" is reserved. PF motors get connected to the top PF connector (output) of Wixy units. GeekServo gets connected to the receiver. Two Wixy units provide enough power to feed GeekServo, otherwise I can plug and extra power from one of B-cable outputs (there is one specific 3-pin one). At the second picture all components are connected. It is important to note, that a Single "Wixy" unit can transmit only 3A to the motors, but it is the maximal power which PF connectors can handle . So you have to use one unit per Buggy motor. Luckily, 3S Lipo as an enormous amount of power, so it can handle 10 Buggy motors easily! Hope I cleared out the "Wixy" setup for you, but if you have any questions left, do not hesitate to ask them!
  10. Great model! I love the shapes and technical part of the car. These time I have nothing to add or remove from your words! Totally agreed! I am planning such a project as well. 1:10 scale is great for RC models, since you can use Land Rover rims and make a realistic steering (which is very important for fast Lego car)!
  11. Yes, there was an RCBricks in the older days and many Lego technic builders in Russia use RC units and controllers to power their cars, since they are cheaper and more affordable in Russia, especially nowadays. The major problem is that their developers can not afford to make a real business of their products yet. All the amazing units and controllers we have for now being made by a single man with a great amount of enthusiasm... I hope we will get ourself a new company such as Buwizz in Russia in the future, but there are no plans about it yet. So there are no products available for sale in the West these days . All I know is that SBrick could be powered by 3S Lipo, if you make a custom connector.
  12. Yes it helps indeed, but the usage of many motors in one car contradict the philosophy of real car engineering, in a way I explained in my first comment. It is impossible to control 12 km/h car with a cell phone on a rough terrain. Likely, there are bluetooth trackpads available which has a proportional control and can used with Buwizz units. Though I had no opportunity to test one of them yet . But both physical and proportional control is not enough to make 20 km RC car controllable, you need a physical feedback. Actually, you you have to seat in the car itself . Nevertheless, it is possible to control a fast RC car on a flat open areas, but it is a little bit boring for me.
  13. Great calculations! I will try such built with: 4 Buwizz motors, slow output 95 mm RC tires "normal hubs", direct connection of motors to hubs via metal U-joint linkage (strong CV linkage). Such setup give a close ratio 95/107 * 5.4/4.5 ~ 1.07 while avoid losses in transmission (friction in planetary hubs, differential). All though such layout provides a signifiant stress on the transmission, so the CV joints will stress a lot under the load (comparing to the layout with planetary hubs). Unfortunately, I will be able to finish these model only in September. So I will report on results later. Agree! The lack of control is significant, and there are several points to consider: A high momentum of a car which drive fast (even bigger momentum of a heavy car driving fast). It provides quite some stress both on the transmission and suspension in tight cornering. A weak steering system. I tried many ways to strengthen the steering system: from increasing the steering arms on the wheel hubs, to the double suspension arms setups... Regardless all the improvements I made, it is all made of plastic, has a significant wobbling (in the connection of a steering rack to steering gear, and in the ball joints of a steering bones). The lack of physical feedback to the driver. It is impossible to control a fast Lego car even with RC proportional system since the driver can not feel the car. Real drivers can hear the noise of the motors, check various sensors in the car, feel most of the bumps and, most importantly, feel the steering wheel resistance (it is well known that of high speed it is harder to steer the wheels). Summing up, it is nearly impossible to control a Lego car which drive over 12 km/h especially of the rough terrain. To understand that clearly, just take a look at fast RC cars which has a tendency to roll over onto their roofs .
  14. You made an interesting research, congrats! I would agree with your conclusions except the second one. Each motor has individual characteristics as well as It`s own areas of application. For example, PF XL motor has a plenty of torque but it is slow. So it is worth to using it in crawlers. But if you want to make a fast car with it you will have to multiply it`s speed with a gearbox, which always takes space, increase weight, has a plenty of friction... Buwizz (Buggy) motor is a lot faster than PF XL motor, so it can be widely used in fast cars. And it was mostly the only "reasonable" area of application for them, until planetary hubs appeared. Combining Buwizz motors with planetary hubs we get a lot of torque on wheels, a reliably working transmission (sipping fast but without big stress). These ideas are agreed with real car engineering. All this was right until you started speak about "high performance". The Weight To Ratio reasoning is very important for real sport cars, and clearly can be applied to Lego models. I am trying to lighten the car as much as I can to make a car with good performance, as well as real engineers does. But real engineers usually does not increase the number of engines in their cars. Yes, there was several two-engine rally cars, but we will ignore them . Engineers try to increase the power of the car by boosting the engine or changing it to a more powerful one. My conclusion from this is the following: If you want to radically improve the performance of the Lego car, you need a more powerful motor. For example, if my car was driven by two PF M-motors, I can upgrade them to PF L-motors. Further upgrade will require Buwizz motors, but what should I do next? I spent a lot of time on this question. My answer to it is the following: Maximal reasonable number of Buggy motors is 1motor per wheel (with minimal number of gears in the transmission, preferably without intermediate gears at all). Further improvement of performance will require a third party motor with greater characteristics, for example one from RC world. Why 4 motors is reasonable? Because real Electric Super Cars use such layout! Buggy motors seems to be the top motors with PF connectors, because PF connectors could melt under higher load (from more powerful motor). So a serious improvment of electronics is required, preferably RC electronics. Further we will need to reinforce suspension, transmission with metal parts. The final result of such upgrades is an RC car in big scale . So if you want a true high-performance car to drive you would better buy yourself a good RC car - it will be faster, stronger, more efficient and cheaper! I like lego RC car and I will stick to them, no matter which limitations they have. Buwizz units and Buwizz motors are great products for Lego cars, which allow to build top RC LEGO vehicles, but they have their own limitations as well as all Lego plastic parts. That is why it is important to understand these limitations and develop new cars very reasonably (balancing between mass and power).