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26

A fan is just 1/4 of a drone, right? Check out this lego drone that actually flies, for inspiration. https://youtu.be/wUVvQk7XLd4 The blade part in question is 89509


17

The easiest way to do this would be to use a motor with a high speed (or gear up a lower speed motor) and then attach one of the larger propeller elements to it. You can probably build a custom prop, but it might be challenging to build something with the proper blade angle while keeping it light and strong enough to not break apart when rotating quickly. ...


16

YES! Philippe Hurbain (Philo) has put together a great and very detailed write-up on those and many other LEGO 9V electric motors. You can find it here: LEGO 9V Technic Motors compared characteristics Your current draw for that specific motor @ 9V is: No load: 65mA Loaded (3.6 N.cm): 310mA Loaded (6.0 N.cm): 480mA Stalled (11 N....


13

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 ...


13

This can be done without a caster wheel as well: Start out with a three wheeled vehicle, with two wheels in the front and one smaller wheel with less traction than the front wheels in the back. All wheels need to be fixed. One of the front wheels is attached to the motor. This might need to have some gearing to get an appropriate speed. The other front ...


11

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 have of ...


10

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 ...


10

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 ...


10

If you're interested in comparing motors regarding to torque and what they can deliver, I would recommend reading Philo's excellent motor comparison page which has a lot of detailed information, very much useful for tinkerers. Of course not all of these motors are readily available nowadays and depending on your project some may be less suitable; but there'...


9

The present line of battery boxes all provide 800mA of current and have overload protection to ensure that this level is not exceeded. Here's what the LEGO website has to say about powering motors: As a rule of thumb, you can drive 2 Power Functions XL-Motors, 3 Power Functions Train Motors or 4 Power Functions M-Motors at the same time from one Power ...


8

There are a number of ways to do this. This is one of the easiest and earliest methods: For that design, you'll need this part (3650): You can also do something similar using a combination of bevel gears or double bevel gears:


8

It is about the right size and shape to be the main shaft of this wind-up motor from set 4093: Here's another view: These pictures show the piece as white, but it might be a variant. I do not have one of these windups to take apart to check.


8

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. ...


8

I'm assuming that you meant "the motor is not powerful enough". Surely you can use a gearing ratio & leverage to assist? Essentially you want the motor to turn many times for each small amount of distance traveled by the lifting arm. This means a small gear on the motor and a large gear driving the lifting. You may need to connect several gears together ...


8

For a comprehensive enumeration and measurements on all motors, refer to Philo's excellent page on this topic: http://www.philohome.com/motors/motorcomp.htm There are some LEGO motors that are missing from this list since they predate the 9V era, like the 4.5V motor, or the 4.5V train motor, but these are probably only of interest if you already own them, ...


8

The motor you have linked is indeed quite old and as far as I know, not compatible with anything newer. Seeing that it works with simple DC current, it wouldn't be hard to construct a converter cable, but it is still some work (especially reducing the voltage from 9V to the 4.5V required by this motor). The next generation (9V system: large motor, ...


7

To work properly, the Forward 5 block on the NXT as well as the Move block of NXT-G require that TWO motors be connected on ports B and C. That's probably the problem you see... To test a single motor, there is the motor block.


7

The simplest way to get different speeds is by changing the gears. The instructions get you to build it with a 12:20 gear down in the portal axles, so the easiest way to change the speed is to flip those to get 20:12. From memory that will not work because it interferes with other parts of the model. You can fit two 16 tooth gears in there instead, giving a ...


7

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 ...


7

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.


7

As an addition to Ambo100's very nicely detailed answer, I'd like to add one more option: If either of the two things you are powering might suffer from friction (or perhaps a child holding it still), the provided solutions result in a lot of torque on the motor and axles, which in turn could lead to damage to those components (although LEGO motors are ...


7

By adding two motors together with gears, you have doubled the torque the motors provide. Power = torque x speed, so if you don't want the doubled power from the motors to go to the torque component but to the speed component instead, I think you should use a differential and put the motors on both outputs of the differential, and use the input to feed your ...


7

The length of the wire is another thing to be aware of. The wire attached to the motor in 8293 is only slightly more than 20 centimeters (might be a few centimeters more, I don't remember), you can double that by putting in the switch which has about the same length of wire, but it's still not much. I don't know how long the wire in 8700 was, but it looks ...


7

Yes, both items contain the same M-Motor part.


7

This is actually a surprisingly difficult task. If you search for similar questions over on the Robotics stack exchange, you will find very smart people who can't even get it right with thousand-dollar localization solutions and graduate-level control theory. If you have a Gyro sensor like Michael suggested, you're on the right track. You can probably get ...


7

That is only 1 stud. So an axle of 5 always stick out 4 studs


6

Assuming that you're asking about the engine in particular, it seems to be a large number of pneumatic engines that have been coupled together in order to supply the required torque. LEGO pneumatic engines typically consist of a pneumatic cylinder driving a crankshaft. Here's a basic picture to give you an idea: The shaft usually also controls a pneumatic ...


6

You need these old school 5292 puppies ;-) 2 of them. Check a motor comparison here You're gonna have to do some after-market mods but those are very powerful , I have them from the 8366 set. But as you can see in the review, there are pro's and con's on every engine. I suggest reading it in full, it's an amazing source of information and you'll learn a ...


6

What you are describing is called backdriving. I teach my students, in principle, not to backdrive the output shaft of a gearbox, motor/gearbox, or servo/gearbox unless they know what's inside of it because you can damage the unit. I use a variety of different robots in my class so what I'm explaining applies to gear drives in general. If you grasp the ...


6

Here's one simple way to accomplish this using just basic parts: This isn't quite a pure Technic example, but that construction is almost exactly what was used on the steam cylinders on Emerald Night: Depending on exactly what you are trying to do, there are also some specialized parts that make building decorative pistons simple. For example, here's the ...


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