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7

Mathematically, the largest driver wheel you can buy for LEGO is Big Ben's XL driver, with a diameter of 36.8mm. To reach 10 mph, that wheel will have to spin: 36.8 mm diameter -> 115.6 mm circumference -> 7.2 x 10^-5 mi/revolution -> 2320 RPM (!!) This means that you have to gear up a motor to run at 2320 RPM. An XL PF motor with no load spins at about ...


6

This seems pretty much bordering on the impossible, given the current state of (LEGO) engineering capabilities. What you are describing is a Von Neumann Machine and as far as I know nobody succeeded in creating one, not just in LEGO but in general. The problems you'd have to overcome: The robot must be capable to exert sufficient force to overcome the ...


3

Aside from the mechanical enhancement, you could also apply more electrical power to the motor. Some LUGs achieve record-breaking train speed by doing just that, although they usually use custom rails as well as transformers. Of course, overpowering motors isn't usually recommended; and for a PF one you'll have the issue of embedding a larger battery; but ...


3

10 mph (16km/h) is a crazy speed at that scale [citation needed]. Chances are quite high that your car will derail even on straight lines. Now, is it possible to reach that speed using lego motors and lego pieces ? I'd say no, but I think you can get quite fast, in the magnitude of 10-12 km/h (6-7.5mph). As stated in another answer, using the bigger train ...


3

You need to ensure that your program has a way to stay alive (wait block, wait for sensor, etc...), otherwise as soon as the program ends all motors are stopped.


3

Generally speaking, the 4.5V motors have higher torque than the higher voltage variants, but run at a much lower RPM. I have never personally tested this particular motor so I can't say specifically. Utility is in the eyes of the beholder. For some people, this would be the exact motor they need. For some, it would be useless. It's hard to say if it ...


3

LEGO "Servo Motor" has little to do with a RC servomotor. To drive it, you need to: Power it at 9V (probably works at 5 volts, but with less torque) through PWR/GND terminals To move in one direction, send a PWM signal (1200 Hz, 0 to 100% duty cycle) on C1 and keep C2 at GND level. As duty cycle varies, servo motor will move along 7 positions on one side. ...


3

To wire 2838 motor, you have to use one PF extension cable, one end connected to PF power source (either battery box or IR receiver), the other end has a 9V compatible plug on bottom. Unfortunately, 2838 also has its connector on bottom, so you also need a 9V cable (such as this one) to connect them.


3

XL (8882): It delivers a maximum torque of 90,4 mNm (600 mA). Without load its rotation speed is around 220 rotations per minute. L (88003): It delivers a maximum torque of 45,4 mNm (450 mA). Without load its rotation speed is around 380 rotations per minute. M (8883): It delivers a maximum torque of 40 mNm (300 mA). Without load its rotation speed is ...


3

Unfortunately it's direct drive so gearing it down really isn't an option. That leaves changing the electrical system. What battery are you using? Fundamentally, any change to the electrical system is going to amount to "use a half flat battery", and if you're using a high-voltage battery now the easy option is to switch to lower-voltage rechargeable ...


2

Is there anyway in which I can use 1 motor for efficient/quick movement while turning left and right? Yes, if you use one motor to drive a wheel and another to steer the vehicle. Using an NXT motor for steering would be quite wasteful however, you should at least use gearing to convert the jittery, fast movement of the NXT motor into slower, more ...


2

When my train was flying off the tracks, I solved the problem by adding more cars to it, or adding extra weight to the existing cars.


2

I agree with HaydenStudios, it is impossible to disassemble completely NXT motor without breaking the orange axle hub. You can nonetheless half-open it enough to see what's happening inside (you need a Torx screwdriver - T10 size if I remember well - to open it. See photos here http://philohome.com/nxtmotor/nxtmotor.htm. Anyway, first try to see what LEGO ...


2

Checking the source code, it appears that the opOutput_Get_Type command is not implemented. In both links, it is mentioned in the comments, but there is nothing in the actual code. Unfortunately, I am not finding a different way to get this information.


2

If the original train motor is not fast enough, you could build your own engine using normal PF motors and use gearing that is suitable for your needs. Then drive your train via stand-alone train wheels:


1

The clicking mode means that you need to reload the firmware on the NXT (under the Tools menu in the NXT software). If you still get the overcurrent shutdown using different cables and different computers, then the conclusion has to be that there is something wrong with the NXT itself. The USB port should be drawing little to no current at all since the NXT ...


1

If the one motor exhibits the same behaviour on any port with any cable and the other motors are working on all of the ports with any cable, then it is safe to say that the problem is definitely with the motor itself. Make sure you swap cables as well as motors to rule out a faulty cable. Also, check for signs of corrosion on the pins of the cables, motors ...


1

Whilst that element is designed to be a "direct drive" system, you could try lifting it up and then stacking some gears on it - however you're going to have some issues with the width of the train/wheels and the track gauge and the amount of gearing you can reliably use because of the size of wheels. In other builds I've seen, the builders have used the ...


1

You can read the tacho count and rotate a negative amount of degrees. Or you may want to use the Navigation class and create a path while you move, then you just need to follow the path back. But unless the robot is perfectly calibrated it will fail miserably. I explain it all here http://thetechnicgear.com/2014/06/howto-calibrate-differential-drive-robot/


1

You can switch 4 pairs of gears on each end of the crawler (2 pairs in the portal hubs and another 2 pairs inside the gearbox infront of the motor) do this on both ends or you run the risk of broken gears or premature motor wear. I ran 12 tooth gears all the way from the motor to my hubs for a dramatic increase in speed however the torque suffered severely, ...



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