6
votes
Accepted
iRobot Create 2 - bypassing fuse for serial port power, other current limitations?
First the disclaimer - if you modify the robot by defeating or replacing the protection features you're on your own.
That being said here is some useful information that will hopefully help you make ...
- 181
4
votes
Accepted
Are robot's codes usually compiled or interpreted?
Robots tend to be portable devices powered by batteries. Portable battery operated devices tend to use embedded processors with limited power and memory. Compiled code has several advantages over ...
- 506
3
votes
Electronic Speed Controller
It depends on the voltage.
Say you are running 12V:
1820W / 12V = 151A
With a 24V system:
1820W / 24 = 75A
- 251
3
votes
Control signal of an LQR Controller
I've gotten stuck in a rut with grasping what the "U" control signal actually refers to in the physical system
But you've written what it is already!
$$
\dot{x} = Ax + Bu
$$
It's whatever ...
- 15.9k
3
votes
How to deal with current spikes due to fast direction-switching motor commands?
I've experienced a similar problem before. For me, the root cause was insufficient battery power. When my motor tried to draw peak power it caused the battery supply bus to brown out. This led to ...
- 15.9k
3
votes
How to deal with current spikes due to fast direction-switching motor commands?
As explained in my answer to What is stall current and free current of motors? when switching direction on a motor, you can end up drawing more than the maximum normal current rating. This can cause ...
- 4,273
3
votes
Can high voltage power lines provide a super highway for drones?
I think yes it can but how? My options are here:
Static system for conventional systems
It should stand or hang to line/pole/special place like birds. Please watch video for an example: https://www....
- 1,124
3
votes
Accepted
Can high voltage power lines provide a super highway for drones?
Sure, a drone can land on a powerline. That's a standard task like the "peg in hole problem" for robotarms. The aim is to maneuver a UAV near to a highvoltage line and eating all the energy. The ...
- 802
2
votes
I need the scheme of iRobot Create 2
The schematic for the main board on the iRobot Create 2 is currently not available. It is advised to remove the plastic top cover before drilling into the electronics below. (This is good practice for ...
- 942
2
votes
How to calculate the current consumed by a brushless motor on a quadcopter
n = Kv * Vin only when there is no load on the motor. When there is a load on the motor, like from a propeller, you will need to be a bit more clever.
For a DC motor (which BLDC motors approximate by ...
2
votes
Accepted
Calculating the resistor for a buzzer
Without a more detailed spec sheet I can't say for sure, but this is my understanding:
The buzzer has a self-drive circuit is rated for input 6V max, at which point it will pull 45mA and oscillate at ...
- 902
2
votes
Accepted
Raspberry Pi and Buzzers: Simple solution
For a beginner, it is always best to follow / copy an existing example. Fortunately, a tutorial about connecting a sound device to a Raspberry Pi and parts are available here. Also, there is a ...
- 506
2
votes
Accepted
How to manipulate the magnetic field around a robot?
The magnetic field is proportional to the current. A fixed geometry coil can generate a field that is positive or negative or zero based on how much current is driven through the coil and which ...
- 4,445
2
votes
Accepted
Why does a motor does not run when a resistor is connected in series between the supply?
You are assuming that your voltage divider will split the 9 volts into 4.5V and 4.5V, but this relies on the upper resistance and the lower resistance values being equal.
The issue you've got is that ...
- 15.9k
2
votes
Why my stepper motor doesn't move when I attach a blade?
I will take a wild guess - your accellerating to fast for the mass of the blade / power of the stepper motor.
You can check this by trying to step much slower - perhaps 1 step per second for testing
- 274
2
votes
Controlling power input for different currents and voltages connected to the same power source
A voltage divider is a bad idea, just for being wasteful if nothing else. How wasteful? Let's consider Ohm's Law:
$$
V = IR \\
$$
where $V$ is voltage in volts, $I$ is current in amps, and $R$ is ...
- 15.9k
1
vote
The Optimal Reduction Ratio
I think there is information missing to analyze the problem.
If that's an rpm-torque graph the fast answer is to search the largest combination of torque*rpm... And for the reduction ratio, 1:1 is the ...
- 46
1
vote
How to manipulate the magnetic field around a robot?
AC motors operate by generating a vector field. The field on the stator rotates, and the rotating field interacts with the field on the rotor (generated, or permanent magnets, or induced) to move the ...
- 15.9k
1
vote
DIY Smart Devices
To learn electronics (which is pretty much essential), then a copy of The Art of Electronics, by Horowitz and Hill (ISBN: 978-0-521-37095-0), is indispensable.
Nevertheless, on its own, it might not ...
- 1,646
1
vote
DIY Smart Devices
where do I start with the electronics?
and
basic accessories and peripherals like cameras, speakers/headphones, lights and some external buttons/controls - Like a helmet with front and rear camera, ...
- 301
1
vote
AC Motors vs Hydraulic motors for skid-steering robot
A hydraulic system requires a hydraulic power unit (hpu), and then you still need a motor everywhere you want an electric motor, and then you've got hydraulic hoses (carrying full hydraulic pressure) ...
- 15.9k
1
vote
How to extract the servo motors of a Digital Micromirror Device?
Mankind does not have such a delicate technology to extract 0.01mm fragile structure from a silicon wafer especially when it is sticked with the rest of the parts firmly. Even if you do it somehow ...
- 1,577
1
vote
Electronic Speed Controller
There are a couple motor metrics that will help you decide:
Motor voltage: Your motor has a range of voltages that it will run effectively at. Pick an ESC whose output voltage(usually the same as ...
- 11
1
vote
How to deal with current spikes due to fast direction-switching motor commands?
It's maybe not this at all, but when a motor or any inductive system suddenly stop it create a short opposite surtense that can affect your microcontroleur. The solution is to ad a flyback diode ...
- 11
1
vote
Are robot's codes usually compiled or interpreted?
Many people use Python to control robots. While it does use more computing resources to interpret the python code, it may take less time for the programmer to develop in an interpreted language.
...
- 572
1
vote
How to deal with current spikes due to fast direction-switching motor commands?
You can try to put a capacitor in the motor terminal. Very close to the motor.
- 497
1
vote
Accepted
Excessive Heat Coming From Video Transmitter and Motor Electronic Boards
All boards come with data-sheets which should list the temperature range of operation for the given board.
Several video transmitter can become quite hot, thus it is recommend to have them into ...
- 1,411
1
vote
Accepted
Wire connectors
Computer fans usually use Molex connectors, however there are different versions of Molex connectors:
https://en.wikipedia.org/wiki/Computer_fan#Connectors
Small LiPo batteries often use JST ...
- 26
Only top scored, non community-wiki answers of a minimum length are eligible