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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 ...


12

Let's take a look. The first step to disassembling the motor is removing the small Philips screw on the bottom: Now there are a pair of gray tabs in the back white section that we need to release. I found it easiest to cut them down with a knife. Once those are free, the white section slides backwards away from the motor. Try to do this gently, as there are ...


12

I was curious about this, and TLG was willing to provide me with one of these motors, so I opened it up. I was able to get the outer shell off by cutting down the 4 tabs on the outside. This motor does not appear to be meant to be opened and put back together. These tabs hold it together very firmly and I wasn't able to move them out of the way without ...


11

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 ...


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

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 the ...


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'...


10

The main difference is that the 88008 Medium Linear Motor includes a rotation encoder with 1° resolution. Otherwise it weighs a bit more (34g vs 43g), is a bit slower (380 rpm vs 255 rpm) but also needs less power (60 mA vs 41 mA when freely running). For more subtle differences see Philo's excellent motor comparison page (where I got the above from as well)....


9

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. ...


9

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

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

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.


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

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 ...


7

Pulleys and gears With a range of pulleys and gears you can build something capable of lifting as much as 100 kilos with LEGO parts, albeit at the risk of putting enormous amounts of stress on the bricks! Using a small gear to power a larger gear (gearing down), you can greatly improve the torque (rotational force) at the cost of reduced speed. Gear ...


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 ...


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