9
votes
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Units for rotational impedance
Radians and unit analysis
The comment by MrYouMath is correct. For the purposes of dimensional analysis, the radian is considered a dimensionless quantity and therefore does not need to be included. ...
7
votes
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Does any know what kind of pump "Colossus" used for saving the Notre Dame Cathedral?
This is not a definitve answer, but since I went to the trouble to look it up I thought i might as well post what I found: Pretty sure there's no onboard pump
As you can see this is a normal firehose,...
- 4,772
5
votes
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Are precision pneumatics possible?
While pneumatic systems can be controlled in a non-discrete manner as GisMofx mentioned, that is generally not the norm because the control system to achieve that movement is more expensive that ...
- 7,904
4
votes
How to design a vacuum climbing robot
You do not need full vacuum to accomplish your goal. A small amount of vacuum pressure adds up really quick over a large surface area. Try to make the entire footprint of your robot under vacuum; your ...
- 7,904
4
votes
How do robots maintain stability?
PID, LQR, and LQG feedback control laws are only small pieces of the solution. Alone, these methods generally cannot solve the problem of balanced bipedal walking.
The reason why is because these ...
- 2,549
4
votes
How can I implement S-curve motion profile on mobile robotic platform / wheeled robot?
There are many ways to create a trajectory between two points using a sigmoid function. It's not a simple question, and the math is a little involved. Here's how I would do it.
Short Answer
You can ...
- 1,220
4
votes
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Torque Problems vs Motor Problem?
The motors have a rated speed of 2750rpm. It doesn't look like there's much of a gear ratio, so at the moment the motors spin at the same speed as the wheels. With 16" wheels, 2750rpm is about ...
- 156
3
votes
How to design a vacuum climbing robot
An important point in the fluid dynamics design is about control points. A simple experiment - hold your hand over a hose on the vacuum cleaner, you'll notice a light vacuum pulling on it, but hold ...
- 5,343
3
votes
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Artificial Intelligence in manufacturing machines
In general terms what you really want from CNC machines is to repeat the same actions exactly the same every time, while you may need to monitor and account for things like tool wear, temperature ...
- 15.2k
3
votes
Are precision pneumatics possible?
Yes, it's possible.
See here:
Position Control of a Pneumatic Actuator
and this youtube video here: Pneumatic Actuator With Position Control on YouTube
Many solutions use a servo controlled ...
- 1,578
3
votes
Can CO2 produce energy to drive a bot
Potentially yes. There are a lot of homemade toys which use a reaction between vinegar and bicarbonate of soda to make simple CO2 jet engines.
However if you want to use this sort of reaction to ...
- 15.2k
3
votes
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4 Gears in a Circular Pattern - Calculating the Proper Distances for Meshing
Let’s consider gears as being represented by a pitch circle on which lie several equally spaced dots with a number equal to the number of teeth. These dots can either represent the teeth or the gaps ...
- 1,317
3
votes
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Kalman filter for sensor fusion — what is the advantage?
You can't just "average the two sensors"
The acceleration readings are essentially meaningless unless you know their direction, you can't know their direction unless you have the platform ...
- 2,472
3
votes
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Small scale manufacturing
I believe the key here is not the material, but the manufacturing method.
I would not recommend a small cnc machine, which seems to be what you're considering. Those are cool and fun, but you will ...
- 1,900
3
votes
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High pass filter and differential equation relationship
It can be noted that the high-pass filter can also be written as
$$
\frac{s}{s + \omega} = 1 - \frac{\omega}{s + \omega},
$$
such that
$$
\frac{s}{s + \omega} Y(s) = Y(s) - \underbrace{\frac{\omega}{s ...
- 1,653
3
votes
How can I calculate a robotic arm's maximum reach?
Total reach is usually the straight line length of each member added together, do work centre to centre.
The manufacturer will specify the total load at a spcific configuration so check the detail.
- 15.5k
3
votes
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Are vacuum actuated artificial muscles as hard to control as the pneumatic ones?
With a vacuum you are limited to the pressure differential between zero and atmospheric (~100kPa or ~15PSI). With pneumatic you are limited to the pressure differential between atmospheric and ...
- 5,237
2
votes
Steering wheel torque when car is turning
It heavily depends on the caster that the suspension is set at. Caster makes the wheels go back to neutral position. The more caster, the more torque is needed to keep the wheel at a position. Scrub ...
- 1,174
2
votes
Accepted
DC brush geared motor: coast vs brake effects on motor/gearhead lifespan
The forces of breaking a motor by shorting its electrical connections are the same as starting the motor with full voltage applied. Actually, they'd only be the same in a ideal motor. In any real ...
- 11.4k
2
votes
How do robots maintain stability?
The robot likely has a body accelerometer & integrates it to use a velocity tracking controller with some sort of explicit or implicit proportional & integral control for the body.
- This ...
- 56
2
votes
How do robots maintain stability?
Clearly there are a lot of different potential solutions to this depending on the application and design approach. Also, as is clear from the video, bipedal robots are still a long way from achieving ...
- 15.2k
2
votes
Strength of human hand compared to robot
I find I have to make a pretty large device to have anywhere near the same power as the human hand.
Is the human hand, cubic centimeter for cubic centimeter just really strong compared to a machine?
...
- 1,943
2
votes
Tug of war robot w/ max torque
I would like to commented this on the question (but I can't due to the 50rep requirement)
I don't know if wheels are obligated or there a other options?
Tracks should give more friction to the ...
- 312
2
votes
Angles Measurement to control (move) a robotic arm
The act of calculating the angles of a robot from the position of the end eflector is called inverse kinematics. Incidenttally the reverse, calculating end efflector position from angles is called ...
- 3,597
2
votes
What is the difference between a bogie and a chassis
A chassis is the term commonly used to describe the overall structure or main structure of almost anything. The case for a computer can be described as the chassis, as it holds/supports/contains the ...
- 6,940
2
votes
Accepted
Purpose of normalization of Jacobian in a parallel manipulator
It is because you are using the trace of the matrix, which is equal to the sum of the singular values. The ideal $\mathbf{JJ^T}$ has singular values all equal to 1, but for an $n \times n$ matrix ...
- 2,472
2
votes
High pass filter and differential equation relationship
You can show it with Laplace transform. Let's say Y = ℒ[y], H = ℒ[η], and ω_p is the filter pole. (Let's not simply call it ω -- when omega is used as a parameter rather than a variable, a subscript ...
- 1,387
2
votes
Accepted
Mechanically increase motor torque
Actually if you want to keep accuracy and increase the torque you can use a gearbox that reduces the input Rpm.
So you will be Sacrificing the speed for the increased torque and precision.
Its also ...
- 24.3k
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