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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 ...


7

It's the main module from Record and Play (set 4095): This part was only included in this set released in 2003. The part contains several motors and some electronics that allow you to record motor movements and then play them back. Pressing the red button would let you record movements for a maximun of 20 seconds by adjusting the motors and the green ...


5

The 12v train motor uses 2-pole 3-slot technology. Because of thinner, but longer wire which results in a greater resistance and will create higher voltage, but lower current the current output isn't enough to drive on-train lights. Since the resistance of on-train lights is constant this will drag down the generated voltage as well.


5

Well, I opened it up without much success, and took some pictures of the process: At first I tried pushing/prying the light grey tabs away from the dark gray "bottom", but those weren't budging So plan B: wedge it apart: It was opening, but I was also distorting the plastic in the process - perhaps if I had a hot air station or something, I could of ...


4

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 ...


4

In this forum thread I have found the following tidbits: "We all know that XL motors can twist axles to their breaking point" This means 40 Ncm, according to Philo. "If you're looking to get max torsional stiffness, then stacked 2L axles + connectors would definitely be much stiffer in torsion than a single long axle." Axles can twist without breaking in ...


4

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 ...


4

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

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

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

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:


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

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 ...


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

I'd like to cover two other techniques that work well, they both transmit horizontal torque to vertical but in slightly different ways that I believe may be useful for different situations. Worm Gears Worm gears are fairly small (less than two studs long). Worm gears are designed to be operated in one direction and can only be driven by the axle with ...


2

There are two attributes in the python ev3dev Motor class called: ramp_down_sp ramp_up_sp Link to documentation: http://ddemidov.github.io/ev3dev-lang-python/ ramp_down_sp Ramp Down SP: read/write Writing sets the ramp down setpoint. Reading returns the current value. Units are in milliseconds. When set to a value > 0, the motor will ramp the power sent ...


2

PosRegSetAngle should set the position of the motor relative to the position the motor was in when regulation was enabled. In what way didn't it work when you tried this? It sounds like you may be asking how to wait for the rotation to finish. I'm not sure if there is a built-in way to do this in NXC or not, but I think that something along these lines ...


2

As you can see in the picture below the friction has to do with driving the worm wheels via regular gears while pushing the unit by hand and yes, I guess the gear teeth on the wheel axles could be damaged because of the gear ratio.


2

It could be that one wheel slips more than the other. This happens when the tires get dirty. Also, you can adjust your center of balance so that more weight is on the drive wheels and they will slip less. You can also use the gyro sensor to compensate for any slippage of the wheels.


1

The adapter itself is generally called a "Molex" adapter. The one you have pictured looks similar to their Mini-Latch style. I would recommend an adapter like this. The pin spacing should be the same even if it is not made specifically for that connector. The red wire connects to pin 1 and the black wire connects to pin 2. The yellow wire is for speed ...


1

The command that you are looking for is setMotorTarget as shown in the documentation here. Essentially, you need to set the target rotation for the motor in degrees and then wait for the movement to take place: //Sets motorA target to 50 degrees at a speed of 100 setMotorTarget(motorA, 50, 100); // Waits for movement to complete ...


1

Looking at your code, you're saying: Set the motors to a speed of 300, acceleration of 1000 Run the motors backwards Pause execution of your program for 500ms Stop the motors If you're not seeing colour id 7, go to 1. Assuming that this was exactly the same code you had on the Brick, I'd guess the delays introduced by the communication will cause a ...


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

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 ...



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