4
votes
Create 2 losing serial communication after toggling full to passive while charging
There is a bug in the implementation of sleep/wakeup on Create 2 which was fixed in release-3.8.2 for robots with an older processor, or release-stm32-3.7.7 for robots with a newer processor. To ...
- 942
3
votes
Accepted
When reading serial data between Arduino and a node, it hangs. How can I properly send and read data?
I found what I believe is a relevant answer here, and I think it's relevant because of the following lines in your serial_server.py file:
...
- 15.9k
3
votes
Accepted
Manipulability Measures of Serial Robots?
The most common manipulability measure is by Yoshikawa [1] which is purely kinematic, ie. it ignores dynamics such as inertia and motor torques. It is simply
$$
\sqrt{\det( J J^T)}
$$
where $J$ is ...
- 1,722
3
votes
Accepted
Do I need the 5V to 3.3V level shifter?
The Roombots example you posted does not use a level shifter because they are using the Create USB cable to talk to the robot. If you are planning to use this cable, you do not need the level shifter. ...
- 942
3
votes
Accepted
Does iRobot 681 have a serial interface?
The 68x series has a Mini-DIN connector on the top surface, toward the robot's right side, but it's now under the translucent diffuser surrounding the buttons. It is held in by snaps. Lift the handle, ...
- 942
3
votes
Accepted
Reading multiple signed digits from serial port
It looks like you're doing this in a very round-about manner. You said,
The matlab function in sumlink is supposed to read the received ASCII characters and add them to a variable until it reaches ...
- 15.9k
2
votes
"Updated" Help in iRobot create serial communication in Arduino
Page 9 of the Open Interface specification gives the following instructions:
Serial sequence: [137][Velocity high byte][Velocity low byte][Radius high byte][Radius low byte]
It then gives special ...
- 15.9k
2
votes
Do I need the 5V to 3.3V level shifter?
I think we need 5-3.3 bidirectional voltage shifter (not for camera) to communicate between raspberry pi and create controller, since serial communication protocols for Create uses 0-5 voltage range ...
- 111
2
votes
Accepted
Communication between Intel Edison and Open Mv7
Seems like the code should work. I can suggest 3 things that might be of assistance.
Make sure you have a prominent Common Ground Sometimes your PC isn't enough
Increase the BraudRate on both ...
- 70
2
votes
iRobot Create 2 -language set error type 2
Scope showed data being sent to the robot. I discovered the console was enabled on the raspberry pi 3 and disabled it; the problem is now resolved.
Specifically, run the following commands
sudo ...
- 21
2
votes
Getting error on serial monitor when using serial controlled motor
Welcome to Robotics, Sam. You've posted your code and the errors you're getting, which is great. There are still a few pieces of information lacking, though. Unfortunately, it looks like the "...
- 15.9k
2
votes
Accepted
Controlling a dc servo with serial communication
You need to read and understand that datasheet.
This board does not have addressing, so without additional hardware you can only have one per serial port.
For a demonstration, use a USB-Serial cable ...
- 572
2
votes
Not able to communicate with Roomba with serial port
Your code looks good, the device is probably sending you back bytes so you need to read them on the port. Adding to what you have, it would look something like this:
...
2
votes
Accepted
how to read and write data with pyserial at same time
It's not entirely clear what you mean by "write and read at the same time" because that can refer to different contexts. It can be confusing because people tend to mix the meanings of full-duplex/...
- 562
1
vote
execute ros2 run command on self wrote packages
This is the important bit in your error:
FileNotFoundError: [Errno 2] No such file or directory: '/dev/ttyUSB0'
It is telling you that python can't find/access ...
1
vote
Accepted
Not getting the correct response from the controller serial communication
I just realized the controller response is actually ?S 1\rS=0\r so with my code I am only getting the first part of the message, so to fix this I just added another ...
- 168
1
vote
Accepted
Roomba s9 -- no communication
Unfortunately, the Roomba S9+ doesn't support the Open Interface spec. So you can't control the robot through the USB port. And neither do any of the other latest generation of Roombas (i.e. the &...
Ben♦
- 5,885
1
vote
Why are serial manipulators almost always made of single dof joints?
Conceptually multiple-dof join is a series of 1-dof joints in sequence. Such decomposition allows you to model your control system and do stuff like inverse- and forward kinematics.
For example - if ...
- 111
1
vote
How do you send multiple data bytes to Irobot Roomba via python serial
I'm not sure if this helps or not, but Discovery models manufactured before November 2005 do not contain the entirety of the SCI set. For more information on this, see the first paragraph of the SCI ...
- 942
1
vote
How do you send multiple data bytes to Irobot Roomba via python serial
I'm not sure if/how pyserial works with a bytearray, but the way it is typically done is with the struct library. Here is some sample code:
...
Ben♦
- 5,885
1
vote
Is this encoder error expected?
This might be "normal", depending on how the signal is acquired. Whenever a signal is derived, timing of the signal acquisition is crucial.
Counting ticks is not time sensitive, as it does ...
- 6,682
1
vote
iRobot Create 2 opcodes, data bytes and Realterm
Found the answer to my own question.
The iRobot needs to be in Safe or Full mode in order to control the LEDs.
So, I was entering the numbers correctly (139 4 0 254), but needed to send the command ...
1
vote
iRobot 600 series OI wake from sleep via BRC
The firmware update described in this answer fixed my problems in this area:
There is a bug in the implementation of sleep/wakeup on Create 2 which was fixed in release-3.8.2 for robots with an ...
- 116
1
vote
Does Create 2 have a built in optical interface (IR remote) using the Open Interface Spec
RoanokeRoboticsClub whoop whoop! I'm based in the Roanoke area!
For your question, I would direct you to the Create2 Open Interface spec, pages 24-26, and ask if that's enough to answer your ...
- 15.9k
1
vote
Get data without command anything from Roomba Create 2
It is a message.
See this page.
https://en.wikipedia.org/wiki/ASCII#Printable_characters
- 600
1
vote
Accepted
How to access UART or serial sensors?
So according to the datasheet from the link provided, the Data interface is indeed UART (LVTTL 3.3V). The datasheet also says it has 2 Modes of operation: Single measurement, continuous ranging 1Hz to ...
- 207
1
vote
Can I use another GPIO pin on the Pi 3 as a RX UART?
This question may sound simple. However it is likely dependent on if the processor's hardware UART resource is mappable to different (functional) pins as well as if the Linux UART driver is flexible ...
- 506
1
vote
Build a drone with a raspberry pi 2 as receiver for the CC3D-LibrePilot
The problem is with the Raspberry pi. You can't generate accurate PWM output using Raspberry Pi because it's a microprocessor running an operating system (not real-time system). So you may get ...
1
vote
Irobot Create 2 Open Interface Communication
The Roomba expects binary data. When you type in the PuTTY terminal, you are sending ASCII data. For example when you type "128" into the terminal, you are actually sending 3 bytes of data: [49 50 ...
Ben♦
- 5,885
1
vote
Irobot Create 2 Open Interface Communication
I was not able to send commands just using putty, because putty sends every character individually. You need to write your own code or use something like https://github.com/xa4a/go-roomba to ...
- 19
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