Questions tagged [motors]
Questions regarding motors. All types of motors, their gearboxes, how to drive an electrical motor etc.
404
questions
2
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1answer
36 views
Calculation for Motor Selection
I need help with the selection of a motor and a motor driver
I need to spin a 700g (65mm radius) round ball at 35,000 RPM. I need to bring it up to speed slowly, so I also need a motor driver/speed ...
2
votes
3answers
69 views
Inverting motor polarities automatically to close and open a door
Hi,
I need to build a device that opens a chicken coop door.
The idea is quite simple, a motor connected to an axle that pulls a string up just like a wench. It would be activated by a relay timer ...
1
vote
0answers
28 views
Equations of motion in matrix form and energy consumption
I am working on Lagrangian derived high-dimensional motion equations for a robot in matrix form. The structure of such an equation is known:
$M(q)\ddot{q}+C(q,\dot{q})\dot{q}+G(q)=0$
In here, $M(q)$, $...
1
vote
1answer
43 views
Can peltier modules be more efficiant with a medium other than air?
Peltier modules are said to be less efficient than conventional air conditioners. Can a medium like moving cold water over the heat sink increase the efficiency of a peltier module? By how much? ...
1
vote
0answers
23 views
How to design an outrunner BLDC motor
I've difficulties to find a good documentation or a book to how to design an outrunner BLDC motor. My propose is, defined RPM and approximative kW and some other parameters, which are calculation ...
2
votes
1answer
41 views
Raise/Lower 350lb Sawmill Head 12v Motor Specs
I am new to this site and have a problem to solve in an area that I’m pretty lost in. I can usually figure stuff out with the help of the internet and some digging but not getting real traction so ...
1
vote
2answers
41 views
Will a motor with 1,16 Nm rotate a 50 mm gear moving about 12 kg
I'm not an expert in mechanics, so this is my question.
I will buy the motor of the image below to move my door.
In the motor shaft, there is a gear with 50 mm of diameter which will move the door.
...
1
vote
1answer
40 views
how much power is needed to move a linear axis
Ι need help calculating the power usage for a linear axis motor. it must move up and down at a maximum speed of 0.5 m/s a load of 50 kg
What I did so far:
The load (i.e. weight) acting on the motor ...
0
votes
1answer
33 views
calculate torsion in a diffrent sized shaft
first of i know it seems like a homework assignment but it does not, it is calculations i need to do at work and it has been a long time since i studied this material. so I need help to calculate if a ...
1
vote
0answers
51 views
What are some techniques for improving stabilization given a mechanical time constant?
Problem: I have a self-stabilizing system that utilizes an intertial measurement unit (IMU) attached to the hull of a vessel. The system self stabilizes by performing matrix rotations based on the ...
0
votes
1answer
29 views
Connecting a custom 3d-printed part to an SG90 servo
I've very recently got into prototyping as I'm working on a project that I intend on making as simple as possible through conventional methods, just to learn general best practices. I have an SG90 ...
0
votes
0answers
27 views
How to switch between two cores (inside the coil) in a simple brushed DC
I am going to build a very simple brushed DC motor. The rotor will not be enclosed in a stator (the rotor will be built on a bench with free space around it), and I will using permanent magnets to ...
0
votes
2answers
39 views
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 ...
0
votes
1answer
25 views
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 ...
0
votes
0answers
24 views
Motor Torque Required in a Reciprocating Compressor
I am working on a Univerity project involving a reciprocating compressor and I am having trouble verifying the motor's torque requirements. I am relatively happy with my calculation method, however, ...
0
votes
0answers
40 views
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 ...
0
votes
1answer
35 views
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 ...
1
vote
2answers
61 views
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 ...
1
vote
3answers
75 views
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 ...
0
votes
1answer
41 views
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 ...
0
votes
1answer
63 views
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 ...
3
votes
1answer
53 views
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.
...
0
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2answers
45 views
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 ...
0
votes
1answer
42 views
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 ...
1
vote
1answer
19 views
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.
1
vote
1answer
57 views
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 ...
0
votes
1answer
58 views
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 ...
6
votes
5answers
987 views
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 ...
2
votes
0answers
73 views
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 \...
0
votes
0answers
26 views
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 ...
0
votes
1answer
43 views
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). ...
0
votes
1answer
33 views
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, ...
0
votes
0answers
15 views
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 ...
1
vote
0answers
60 views
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 ...
0
votes
2answers
77 views
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?
...
0
votes
3answers
99 views
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 ...
0
votes
2answers
41 views
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 ...
2
votes
1answer
58 views
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&...
0
votes
1answer
55 views
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 ...
0
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0answers
23 views
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, ...
2
votes
1answer
31 views
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/...
1
vote
2answers
48 views
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 ...
2
votes
0answers
42 views
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 ...
4
votes
5answers
142 views
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 ...
2
votes
3answers
61 views
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 ...
0
votes
0answers
23 views
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 ...
0
votes
0answers
10 views
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 ...
0
votes
2answers
48 views
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 ...
1
vote
0answers
47 views
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 ...
0
votes
1answer
33 views
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 ...
