Questions tagged [motors]
Questions regarding motors. All types of motors, their gearboxes, how to drive an electrical motor etc.
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Mechanically increase motor torque
An electrical engineer here. Using a stepper motor for a robotic arm. A stepper motor at the base of the arm has a max holding torque of 6kgcm. The arm is around 30cm in length from this base motor ...
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Making a three phase squirrel cage induction motor in PLECS?
I was just curious if I was to make a Three phase squirrel cage induction motor connected to a
mechanical load System Block Diagram in PLECS with a rated frequency of 60hz, 6 poles, 220V rated stator ...
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What is the feedback signal used in the speed control of a brushless DC motor?
In a brush-less DC (BLDC) motor the commonly used speed is sensed using the feedback from Hall effect sensors and the back or counter EMF. The linked article on Wikipedia also mentions that 'Other ...
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What is the difference between a single-stage pump and a centrifugal pump?
Here is the small $12 \; V$ pump that I am looking at. The manufacturer called the product as DC brushless centrifugal circulation small water pump but under its description it mentions that it is a ...
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Is a pneumatic cylinder in general a linear or rotary actuator?
I've just begun to learn pneumatics and I'm really confused where the pneumatic cylinder falls under in the categorization of what kind of mechanical motion it is suppose to produce. I've seen one ...
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What Goes Into Making a Variable Field Magnetic Motor?
(I feel it is necessary to mention that I am not an electrical or mechanical engineer; I just like to build fun things.)
I've already got a good explanation of the concepts involved in a variable ...
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How does the efficiency curve of a well pump shift with speed?
Well pump manufacturers publish "efficiency curves" for well pumps, such as this one (the curve that is most sharply convex down, whose Y axis is read from the "% EFF" scale on the ...
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Is there a difference between a "brushless motor" and a "motor without brushes"?
On the Dyson website they promote their new motor by saying:
Dyson Hyperdymium™ motors work very differently to conventional
brushed motors. We replaced the brush with digital pulse technology,
added ...
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Improving ball feeder design
I designed this ball feeder for my robot however I'm experiencing frequent ball jams as the ball is stuck against the wall of the hole entry or just a ball being moved left and right not entering the.
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Can DC motors be used for regenerative braking only? [duplicate]
I am an engineering student working on a machine to tension steel wire rope for maritime uses. The wire rope (max, ~2000m, diameter 44mm) sits (without tension) on a spool (diameter 2m) and has to be ...
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Back EMF from a motor
I have a large DC Motor I ripped out of a treadmill and I'm curious if the back emf generated from manually rotating the motor is a DC output or an AC output. Is it AC only when it's from the power ...
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What size of fan requires motors with a transmission? [closed]
I am wondering at what fan size/speed a direct drive motor is no longer sufficient to drive a fan? Phrased alternatively, what size/speed of fan requires motors with a transmission? For an axial fan.
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Running Hydraulic Pump with High Torque Motor
It's my understanding that hydraulics are merely a means of gear reduction to move a given object. So then I'm wondering why I can't find a formula or way to determine the following issue:
I want to ...
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How do I interpret this DC motor datasheet?
Problem summary:
I need to produce about 0.289 Nm with a rack and pinion system and compress 24 mm of a 110 mm x 21.6 mm, 0.99 N/mm steel spring.
I thought about using with a 10mm pitch diameter gear ...
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Ways to brake an axle
I am currently studying Mechanical Engineering and am doing an assignment where I have to design a wire rope tensioner where a wire rope is unspooled from a drum, but the wire has to be at a specific ...
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Advice on spring launcher project
I found an ingenious design of a spring ball launcher on grabcad and I'm interested in adapting it to accelerate a $43.7 \mathrm{~mm}$ diameter, $45 \mathrm{~g}$ golf ball enough to reach $65.5 \...
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Mecanum wheels begin to make robot spin around rather than move to the side
I am using mecanum wheels to steer my robot which I am programming using an arduino. The main problem that I am having is that whenever I attempt to make the robot move sideways like this:
Instead ...
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What would the tension in the cable be?
A subsequent question stemming from here A massless motor is attached to a massless pulley(the blue circle) with a fixed rotational inertia and they are all attached to a mass X (the green platform). ...
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How to calculate the Torque required to rotate two bars perpendicular to each other
This question relates to a previous question (How to calculate the required torque in a static equilibrium system) where I have enquired about the start-up torque required to rotate a system. However, ...
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how does one obtain motion in the theta and phi direction with motors?
I'm not a mechanical engineer,but I'm guessing this is something that is well known by MEs. Say I have a rod and I want to move my pitch one direction, and my azimuth the other direction. How can I do ...
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VFD or soft start to minimize power consumption on starting a motor?
I want to use the smallest generator possible to run a standard three-phase AC well pump. According to this website and others, it is advisable to use a generator capable of 3x the running kVA if the ...
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Torque required to start rotating a wheel about its center
Assuming i have a circular disc of a significant mass and diameter. Neglecting friction, if a motor is put at its center how do i calculate the torque required for the wheel to just start to rotate?
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how can I control 2 stepper motors with RS-232?
Hello everyone this is my first post to the forum. I want to control 2 stepper motors using RS-232 as a way of directly communicating with step drivers from my desktop. I am new to communication ...
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Two 3/4HP / 500W motors to run in opposite directions, at precisely the same RPM, controllable from zero to 5000 RPM?
I am designing a machine where I need two 3/4HP / 500W motors powered from 110VAC to run in opposite directions, at precisely (+/- 0.3% perhaps) the same RPM, controllable from zero to 5000 RPM by a ...
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Automatic compression of springs
I am trying to design something for a friend, but am struggling to come up with the mechanics. Can you help?
So imagine a long extendable pole, like a bow staff. Imagine after pulling out a "peg&...
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controllable low RPM motor
I am looking for a (rather cheap) low RPM controllable motor. If it could turn in both directions (also controlled) that would be a huge plus. Any ideas?
Right now I'm using a disco ball motor at 1 ...
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Can I benefit from using a real axle as a shaft of a brushless motor on my RC car?
I'm designing an RC car and considering two options now. I can put some gears into it, so that I would have a certain gear ratio between motor and axle, or I can remove shaft from the motor and, ...
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How to size motor to pull up a slope
I am trying to understand how to size an electric motor to pull a person up a sloped incline.
I know that I need to take into account the speed desired, the weight of the person and the friction/...
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Selecting the right DC motor for horizontal motion
I have come across a problem that for the life of me I can't seem to figure out. I'm sharing this here in the hopes that the amazing community here can help push me in the right direction.
The problem ...
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Overcurrent protection, limit for nominal current or stall?
Background: I'm currently working on a robotics design that will drill through soil.
I have selected a 48V motor who's nominal current is 3.17A and has a stall current of 42A. I will be driving the ...
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Preventing a DC motor from stalling
My team is trying to build a mechanical cannon for a final project for a course and we are running into some problems with our motor stalling.
Our motor stalls when the plate hits either side of this ...
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Relation between armature voltage and mechanical power in electrical Engineering
I am searching for an effect chain that leads to the mechanical power $P_{mech}$ of a DC motor, starting with the applied armature voltage $U_{A}$. My request also includes all the electrotechnical ...
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Absolute Digital Encoder Speed measurement
I am using a 16-bit absolute magnetic encoder and I get the position from SSI 3 wire, I mean digital outputs for my position control application. I have a problem with getting accurate speed data. I ...
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Petrol-Electric transmission drivetrain parameters
Pardon me if this question covers too many elements;
I am not yet informed enough to fully comprehend what would be the important parameters which must be matched for such a system to work, which is ...
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How to calculate the required torque in a static equilibrium system
I am working on a personal project where I need to select a motor to rotate a system that is in static equilibrium. The motor torque specification is given in kg.cm.
This is what I have:
Bar : 2 ...
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Building a custom indirect actuator, any thoughts?
I’m trying to create a custom indirect actuator, that is controlled by a microcontroller, for a custom robotics project.
I have selected motor and gears (according to Fd = W = T2*pi) so that the ...
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Fixing a stepper motor by its shaft
Suppose I have a small stepper motor, and for reasons (like wiring considerations) it is advantageous for me to not actually have the motor's body fixed as the shaft rotates, but rather have the shaft ...
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Controlling torque required to turn a shaft
I have an shaft/crank that will be turned by the user.
I want to precisely and dynamically control the torque required to do so.
For simplicity we can think of it as a exercise machine (so the torque ...
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Power a microcontroler with a motorcontroller?
I have a motor controller that operates at 10-50V and draws 5A controlling a 3V motor that draws less than 1A.
I had a an idea where I want to try to use a microcontroller to control this set up.
The ...
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Where/why would grease be required on this electric motor?
Here's the nameplate from a 5 HP single phase electric motor - used in an air compressor:
Note that it reads:
HIGH TORQUE GREASE BEACON 325
which I interpret to mean that you should use high ...
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DC Motor stops working for a couple if time at cold start every time
We have a DC motor that is connected to the track with couplers. Every day at cold start (when it hasn't run for sometime), when we start the motor while moving up (Z-axis) the motor stops (brakes ...
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Can we make a motor without a permanent magnet and with wireless energy transfer?
If we could transfer energy wirelessly with 100% at short range. Then what if we create a motor that have both stator and rotor be an electromagnet? By putting a magnetic coupling to transmit energy ...
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How to calculate the torque for motors for a Core XY movment?
I am trying to design a simple setup that follows the core XY movement shown:
I have been researching the statics behind this movement in order to calculate the minimum torque for the motor so I ...
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PMDC Motor Characteristic Graph
I am trying create a graph similar to as shown below. However, I am confused as to how the torque is related to the characteristics.
The graph that is to be replicated for certain parameters:
The ...
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How do electric vehicles' motors run at high speeds above 10000rpm?
For example, for a squirrel cage induction motor, the speed of operation is given by
Ns = 120*f/P
depending on the number of pole pairs and supply frequency. Now the supply frequency is 50/60Hz while ...
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What forces to consider on a tracked vehicle?
I'm aware that when calculating the power necessary to move a wheeled vehicle I should consider the rolling resistance, gradient resistance, air resistance and if it's a stopped vehicle the ...
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With ebikes, is there friction from the motor when riding with the electronics turned off?
One may want to ride an electric bike with the electronics turned off. There are many reasons to do this, i.e. flat battery, fitness (who would have thought)
When riding an ebike conventionally, is ...
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Sizing electric motor
I've been looking for a way to size an electric motor for a vehicle that could be assumed as a box-shaped load with a mass of 60 kg, up a 10° incline, at 1.6 m/s, using continuous tracks with 1 motor ...
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Can you make the magnets rotate inside the coils of Brushless motor?
I know that current brushless motors, have a non rotating core made of copper coils, with permanent magnets on the outside rotating around it, and eventually connected to a shaft. But i was wondering,...
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On using gears and a low powered motor
I have system I want to move with a DC motor that requires about 1 kW of power when taking into account rolling resistance, drag resistance and when moving on an inclined plane with a specific ...