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Lego: Random Ideas and Tools for EV3 Brick Running ev3dev Linux

This repository stores my personal experiments with ev3 brick running ev3dev linux. Most of it is not sufficiently general but it may still serve as a source of ideas for others.

The files .history-* are my local bash histories, for finding how I ran what.

Connecting via Bluetooth

brickman: Wireless->Bluetooth->scroll to my paired NB Network Connection -> Connect ...Bluetooth icon gets green instead of white in Mate side panel ...but leads to GDBus.Error:net.connman.Error.Failed: Input/output error

Remove devices from both devices Switch off both bluetooths. Fire up brick BT, Make brick visible Open BT devices on NB Search Click on ev3dev Pair Confirm pairing on both devices Then scroll to NB-device in brickman click Network Connection click Connect (not connect directly) On NB CONFIRM. The window gets often hidden somewhere, so this tends to timeout... Brickman should go over Associating to Connecting to Connected

Basic Commands

ssh robot@ev3dev.local
# heslo maker
python3
ev3.Sound.speak('Welcome!').wait()
m = ev3.LargeMotor('outB')
m.run_timed(time_sp=1000,speed_sp=500)

Creating a fresh robot card

Download from EV3DEV:

Find out the correct device (here /dev/mmcblk0) e.g. by checking gnome-disks.

Flash it simply with dd:

sudo dd if=ev3dev-stretch-ev3-generic-2020-04-10.img of=/dev/mmcblk0 bs=4M && sync

Populating fresh robot card

# connect, e.g.
ssh robot@192.168.0.105

# installing core packages I need
sudo apt-get update
sudo apt-get install gawk
sudo apt-get install python3-pip ## downloads 82 megs! Considering it for rpyc

# upgrading only ev3dev-python:
sudo apt-get update
sudo apt-get install --only-upgrade python3-ev3dev

git clone https://github.com/obo/lego.git
# use our bashrc and vimrc:
bash lego/environment/setup_environment.sh

numpy and scipy on EV3

Highly recommended to use Debian pre-compiled packages, i.e.:

sudo apt install python3-numpy python3-scipy

Interesting Ideas from ev3dev Python Demos

git clone https://github.com/ev3dev/ev3dev-lang-python-demo.git

ev3dev-lang-python-demo/robots/R3PTAR/r3ptar.py ... ukazuje vicevlaknovost ... cili tim by melo jit udelat rizeni a soucasne moznost zapnout sledovani cary

ev3dev-lang-python-demo/robots/EV3RSTORM/ev3rstorm.py ... zahrnuje kresleni na display! Cili tim by se dalo delat nejake malovani mapy, kudy projel

Multipurpose Track3r Proposal

  • vicevlaknova aplikace
  • triggery na 4. kanalu IR pro ovladani nabidky
  • tank na 1. kanalu
  • pomalejsi tank na 2. kanalu V nabidce:
  • sleduj caru
    1. Rozhledne se vlevo a vpravo, tim pozna barvu cary a okoli, a taky tloustku cary.
    2. Vyrazi po care, zastavi na jakekoli jine barve nez cara nebo pozadi.

Inspiring Youtube Videoss

http://www.mindcuber.com/mindcub3r/mindcub3r.html http://www.mindcuber.com/mindcub3r/MindCub3r-v1p0.pdf

https://www.youtube.com/watch?v=JlWOKaxKrIE ...reptar a kocka

https://www.youtube.com/watch?v=uIPrN-b-Zb0 ...spybot, dobry pasovy

https://www.youtube.com/watch?v=JOUGsgqYraE ...ruka

https://www.youtube.com/watch?v=bSmXZyNWm28 ...tridic lentilek

https://www.youtube.com/watch?v=5VAhH7GUoks ...hledani veci

https://www.youtube.com/watch?v=cXgB3lIvPHI ...hraje na kytaru

https://www.youtube.com/watch?v=FCWNNk1G2UU ...had, slon

https://www.youtube.com/watch?v=6xCd55oSgO4 ...hromska krabice

https://www.youtube.com/watch?v=dIgSKPzLC9g ...telegraf

https://www.youtube.com/watch?v=0d0ktACCwT4 ...best of evdev

https://www.youtube.com/watch?v=LZYr646Ul4Q ...spirograph

https://www.youtube.com/watch?v=0Aw23jQkP2g ...gearbox

Other interesting links:

Camera: https://siyahodacom.wordpress.com/2017/10/01/adding-webcam-to-ev3-ev3dev/

Camera-based line tracking: http://karandashsamodelkin.blogspot.cz/

Pixy-camera: http://www.ev3dev.org/docs/tutorials/using-pixy-camera/

lejos opencv face recognition: http://thinkbricks.net/face-tracking-on-ev3-using-lejos-0-9-1/

https://github.com/Klabbedi/ev3 ...a better line follower, PID algorithm (but this will not work on red lines, because in reflected-light scanning, red led is used, so red is the same as white)

http://pazhong.net/code/number_detect/number_detect.py ... number detection and draw it on screen

https://github.com/dlech/ev3dev-photo-booth

and a similar tutorial in C++: https://github.com/FrankBau/raspi-repo-manifest/wiki/OpenCV

https://github.com/YuliangXiu/PoseFlow ... online pose tracking for human body

Trying to get my old Logitech camera running

lsusb Bus 001 Device 003: ID 046d:08ae Logitech, Inc. QuickCam for Notebooks

sudo hwinfo --usb 04: USB 00.0: 11200 TV Card [Created at usb.122] Unique ID: ADDn.elweGVRLXdD Parent ID: k4bc.BtRjRTLQ986 SysFS ID: /devices/platform/ohci.0/usb1/1-1/1-1:1.0 SysFS BusID: 1-1:1.0 Hardware Class: tv card Model: "Logitech Camera" Hotplug: USB Vendor: usb 0x046d "Logitech, Inc." Device: usb 0x08ae "Camera" Revision: "1.00" Speed: 12 Mbps Module Alias: "usb:v046Dp08AEd0100dc00dsc00dp00icFFiscFFipFFin00" Driver Info #0: Driver Status: zc0301 is not active Driver Activation Cmd: "modprobe zc0301" Config Status: cfg=new, avail=yes, need=no, active=unknown Attached to: #3 (Hub)

dmesg [ 4957.057832] usb 1-1: USB disconnect, device number 2 [ 4968.794243] usb 1-1: new full-speed USB device number 3 using ohci [ 4969.013560] usb 1-1: New USB device found, idVendor=046d, idProduct=08ae [ 4969.013649] usb 1-1: New USB device strings: Mfr=0, Product=2, SerialNumber=0 [ 4969.013705] usb 1-1: Product: Camera

uname -r 4.4.87-22-ev3dev-ev3

The issue where I ask for help: ev3dev/ev3dev#64

This is what could possibly help: I installed the kernel options: gspca (in v4l) and USB audio (in alsa USB devices) and then inserted the corresponding modules: zc3xx and snd_usb_audio.

Connecting via USB cable

There is a tutorial: http://www.ev3dev.org/docs/tutorials/connecting-to-the-internet-via-usb/

But it didn't really work for me.

When brickman connected to wired connection and has shown me its IP address, I manually configured my NB for that network:

ifconfig enp0s20f0u3 169.254.214.1

ssh robot@169.254.214.149

On the robot: sudo ifconfig myip=$(sudo ifconfig | sed -n 's/.inet ([0-9][0-9.]).*/\1/p' | grep -v 127.0.0.1) sudo /sbin/route add default gw $(echo $myip | cut -d. -f1-3).1 echo "nameserver 1.1.1.1" | sudo tee /etc/resolv.conf

And on my laptop: (this may have not been necessary, not sure) echo 1 > /proc/sys/net/ipv4/ip_forward sudo modprobe ip_tables sudo modprobe ip_conntrack sudo modprobe ip_conntrack_irc sudo modprobe ip_conntrack_irc sudo modprobe ip_conntrack_ftp sudo iptables -t nat -A POSTROUTING -o wlp4s0 -j MASQUERADE ... to forward robot's network through my NB

Still some problems:

[ 2540.370361] usb 1-1: new full-speed USB device number 2 using ohci-da8xx [ 2540.643482] usb 1-1: New USB device found, idVendor=046d, idProduct=08ae [ 2540.643546] usb 1-1: New USB device strings: Mfr=0, Product=2, SerialNumber=0 [ 2540.643581] usb 1-1: Product: Camera
[ 2542.272748] Linux video capture interface: v2.00 [ 2542.395353] gspca_main: v2.14.0 registered [ 2542.471259] gspca_main: gspca_zc3xx-2.14.0 probing 046d:08ae [ 2543.313943] input: gspca_zc3xx as /devices/platform/soc@1c00000/ohci-da8xx/usb1/1-1/input/input2 [ 2543.344797] usbcore: registered new interface driver gspca_zc3xx [ 2544.366522] usbcore: registered new interface driver snd-usb-audio

robot@ev3dev:~/lego$ streamer -f jpeg -o image.jpeg files / video: JPEG (JFIF) / audio: none fifo max fill: audio 0/0, video 1/16, convert 1/16

Taking pictured from camera

streamer -f jpeg -o image.jpeg

Recording sound through USB camera

arecord -D plughw:1,0 -t wav --duration=5 test.wav ... worked out of the box

http://ofalcao.pt/blog/2017/lego-voice-control-ev3

OpenCV links

https://www.pyimagesearch.com/2014/07/21/detecting-circles-images-using-opencv-hough-circles/

https://thecodacus.com/opencv-object-tracking-colour-detection-python/#.WuB4pta-lUA

Connecting via wifi [solved]

ev3dev/ev3dev#1082

lsusb: Bus 001 Device 003: ID 083a:4505 Accton Technology Corp. SMCWUSB-G 802.11bg

hwinfo --usb 07: USB 00.0: 0000 Unclassified device [Created at usb.122] Unique ID: lfzD.wkm1Arvlfj3 Parent ID: ADDn._cOmnuCBvb4 SysFS ID: /devices/platform/soc@1c00000/ohci-da8xx/usb1/1-1/1-1.1/1-1.1:1.0 SysFS BusID: 1-1.1:1.0 Hardware Class: unknown Model: "Accton SMCWUSB-G 802.11bg" Hotplug: USB Vendor: usb 0x083a "Accton" Device: usb 0x4505 "SMCWUSB-G 802.11bg" Revision: "48.10" Speed: 12 Mbps Module Alias: "usb:v083Ap4505d4810dcFFdscFFdpFFicFFisc00ip00in00" Config Status: cfg=new, avail=yes, need=no, active=unknown Attached to: #8 (Hub)

ifconfig usb1: flags=-28669<UP,BROADCAST,MULTICAST,DYNAMIC> mtu 1500 ether 22:16:53:5f:74:d2 txqueuelen 1000 (Ethernet) RX packets 0 bytes 0 (0.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 0 bytes 0 (0.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

lsmod Module Size Used by sr_mod 12624 0 cdrom 28732 1 sr_mod snd_usb_audio 139864 0 snd_hwdep 5257 1 snd_usb_audio snd_usbmidi_lib 19259 1 snd_usb_audio snd_rawmidi 19974 1 snd_usbmidi_lib snd_seq_device 4207 1 snd_rawmidi gspca_zc3xx 41388 0 gspca_main 22080 1 gspca_zc3xx v4l2_common 4978 1 gspca_main videodev 127782 3 v4l2_common,gspca_zc3xx,gspca_main iptable_nat 1728 0 nf_conntrack_ipv4 5927 1 nf_defrag_ipv4 1634 1 nf_conntrack_ipv4 nf_nat_ipv4 5140 1 iptable_nat nf_nat 14692 1 nf_nat_ipv4 nf_conntrack 87388 3 nf_conntrack_ipv4,nf_nat_ipv4,nf_nat libcrc32c 1100 2 nf_conntrack,nf_nat usb_f_rndis 15528 2 usb_f_ecm 6278 2 u_ether 12402 2 usb_f_ecm,usb_f_rndis ev3_uart_sensor_ld 7767 2 ev3_uart_sensor 13506 1 ev3_uart_sensor_ld nxt_i2c_sensor 35440 1 ev3_uart_sensor servo_motor_class 6378 1 nxt_i2c_sensor hci_uart 16410 0 serdev 8117 1 hci_uart suart_emu 23989 0 ev3_analog_sensor 5077 0 uinput 8046 0 libcomposite 41550 16 usb_f_ecm,usb_f_rndis configfs 28703 4 usb_f_ecm,usb_f_rndis,libcomposite ip_tables 10235 1 iptable_nat x_tables 19232 1 ip_tables

robot@ev3dev:~$ ev3dev-sysinfo -m

System info (from ev3dev-sysinfo)

Image file:         ev3dev-stretch-ev3-generic-2018-04-22
Kernel version:     4.14.35-ev3dev-2.0.0-ev3
Brickman:           0.10.0
ev3devKit:          0.5.2
Board:              board0
BOARD_INFO_HW_REV=8
BOARD_INFO_MODEL=LEGO MINDSTORMS EV3
BOARD_INFO_ROM_REV=6
BOARD_INFO_SERIAL_NUM=0016535F74D2
BOARD_INFO_TYPE=main

Brickman says Wifi: Not available

2018-05-08

After a kernel update, Brickman can power up wifi, but Start Scan says: DGBus.Error:net.connman.Error.NoCarrier. No carrier

Fixed by adding the correct firmware from:

https://sourceforge.net/projects/zd1211/files/zd1211-firmware/

After powering the wifi off and on, scan was possible.

However, picking my wifi and trying to connect failed with: GDBus.Error:net.connman.Error.OperationAborted: Operation aborted ...this was actually due to my MAC filter where I allowed a different MAC address than the dongle presented now. I can't understand where I copied the wrong MAC address from in at the first attempt.

Mouse input?

ls /dev/input/by-id/ should say: usb-0461_USB_Optical_Mouse-event-mouse

Following mouse is implemented here: follow_mouse: https://github.com/cavenel/ev3-print3rbot/blob/master/writer.py

LCD

Use: brickrun ./command

sudo openvt -s -w -- sudo --user -- COMMAND ...this should allow me to run the COMMAND with access to the screen

Another way to connect to the virtual console through ssh: sudo chvt 6

same as typing ctrl-alt-F6

sudo conspy

http://www.ev3dev.org/docs/tutorials/using-ev3-lcd/ https://sites.google.com/site/ev3python/learn_ev3_python/screen

My issue: ev3dev/ev3dev-lang-python#463 ...should still confirm the booth

The photo booth works (gets pictures), but does not show them on screen. This is probably the error message: ** (brickrun:1826): CRITICAL **: brickrun.vala:100: Failed to send signal: GDBus.Error:org.freedesktop.DBus.Error.UnknownMethod: No such method 'SignalGroup'

QR code reader:

https://www.learnopencv.com/barcode-and-qr-code-scanner-using-zbar-and-opencv/

http://aishack.in/tutorials/scanning-qr-codes-2/

https://gist.github.com/mohankumargupta/243aeb6787123cc17f1c10338bd4a82f ...this seems to be all combined into one script

Aruco Markers, better than QR codes:

https://www.sciencedirect.com/science/article/pii/S0031320317303151 ...perhaps the best option http://www.uco.es/investiga/grupos/ava/node/57 http://www.uco.es/grupos/ava/node/25

https://docs.opencv.org/3.4.1/d5/dae/tutorial_aruco_detection.html

PnP OpenCV has method solvePnP

keywords: slam, simultaneous localization and mapping

https://openslam-org.github.io/

https://arxiv.org/pdf/1610.03660.pdf Image Based Camera Localization: an Overview Yihong Wu, Fulin Tang, Heping Li

Installing Aruco:

get from here: https://sourceforge.net/projects/aruco/files/?source=navbar

cd aruco mkdir build cd build cmake -DCMAKE_INSTALL_PREFIX:PATH=/home/bojar/opt/aruco-3.0.11 .. make make install

cd markermapper mkdir build cd build export aruco_DIR=/home/bojar/opt/aruco-3.0.11/ cmake .. make

Simplest white balance:

https://gist.github.com/tomykaira/94472e9f4921ec2cf582 paper+code: http://www.ipol.im/pub/art/2011/llmps-scb/?utm_source=doi

USB Camera button

https://unix.stackexchange.com/questions/398660/detecting-usb-camera-button-event

Beacon Seeker

see random-bits/report-beacon-location.py

0 -128 ... means that no beacon is found 0 1 ... means that we are really really close

11 54 ... means that at "angle" 11, 54 "cm"

Note that it can't distinguish front and back, so we will have to realize that when we try to roll towards but get further, we probably need to rotate...

Or put differently, we should first stabilize the angle and only then focus on the distance.

Steering

steering3 doesn't work at all, ignores the change.

Course: 295.63783698408236 , Left: 40 , Right: 40.0 Course: 278.2177484737596 , Left: 40 , Right: 40.0 Course: 285.1530424270078 , Left: 40 , Right: 40.0 Course: 285.3336692939426 , Left: 40 , Right: 40.0 Course: 280.5610942447775 , Left: 40 , Right: 40.0 Course: 264.02855443500306 , Left: 40 , Right: 40.0 Course: 253.69647100177943 , Left: 40 , Right: 40.0 Course: 246.29642562886042 , Left: 40 , Right: 40.0 Course: 153.73717076689826 , Left: 40 , Right: 40.0 Course: 148.49593456078 , Left: 40 , Right: 40.0 Course: 160.43838775570993 , Left: 40 , Right: 40.0 Course: 203.88310612648385 , Left: 40 , Right: 40.0 Course: 162.86323496452164 , Left: 40 , Right: 40.0 Course: 118.7518368606886 , Left: 40 , Right: 40.0 Course: -27.32580003400672 , Left: -18.139359972794622 , Right: 40 Course: -193.01178484332874 , Left: 40.0 , Right: 40 Course: -208.61163282385814 , Left: 40.0 , Right: 40 Course: -199.13916193295287 , Left: 40.0 , Right: 40 Course: -167.95320071053493 , Left: 40.0 , Right: 40 Course: -145.75692942290914 , Left: 40.0 , Right: 40 Course: -150.46866580834674 , Left: 40.0 , Right: 40 Course: -166.23221224603807 , Left: 40.0 , Right: 40 Course: -172.32239497128228 , Left: 40.0 , Right: 40 Course: -206.31446988052232 , Left: 40.0 , Right: 40 Course: -235.97961153989553 , Left: 40.0 , Right: 40 Course: -229.70066500212323 , Left: 40.0 , Right: 40 Course: -213.9761825924693 , Left: 40.0 , Right: 40 Course: -203.31686643334615 , Left: 40.0 , Right: 40 Course: -193.18282078522884 , Left: 40.0 , Right: 40 Course: -184.6898381805486 , Left: 40.0 , Right: 40

Testing new design of pen holder

import ev3dev.ev3 as ev3 from ev3dev.auto import OUTPUT_A, OUTPUT_B, OUTPUT_C, OUTPUT_D from ev3dev.helper import MediumMotor m=MediumMotor(OUTPUT_A) m.run_to_abs_pos(speed_sp=80, position_sp=30, stop_action="hold")

pens up

m.run_to_abs_pos(speed_sp=80, position_sp=0, stop_action="hold")

left pen down

m.run_to_abs_pos(speed_sp=80, position_sp=60, stop_action="hold")

right pen down

Mouse in python:

import evdev device = evdev.InputDevice('/dev/input/by-id/usb-04d9_0499-event-mouse') device.capabilities() {0: [0, 1, 2, 4], 1: [272, 273, 274], 2: [0, 1, 8], 4: [4]} device.capabilities(verbose=True) {('EV_REL', 2): [('REL_X', 0), ('REL_Y', 1), ('REL_WHEEL', 8)], ('EV_SYN', 0): [('SYN_REPORT', 0), ('SYN_CONFIG', 1), ('SYN_MT_REPORT', 2), ('?', 4)], ('EV_KEY', 1): [(['BTN_LEFT', 'BTN_MOUSE'], 272), ('BTN_RIGHT', 273), ('BTN_MIDDLE', 274)], ('EV_MSC', 4): [('MSC_SCAN', 4)]}

Further details: http://www.antony-jordan.co.uk/python-evdev.html?i=1

Working example: random-bits/report-mouse-moves.py

Possibly simpler solutions: https://stackoverflow.com/questions/25848951/python-get-mouse-x-y-position-on-click

Mouse Odometry:

http://www.ijcas.org/admin/paper/files/IJCAS_v2_n4_pp485-493.pdf ...one mice could be enough??

https://pdfs.semanticscholar.org/a219/ba7106fc63f4af5ddf7fac7b407c49af2b46.pdf ...two mice needed!

https://link.springer.com/chapter/10.1007/978-1-4020-5626-0_18 ...precise, but even more mice needed

https://ieeexplore.ieee.org/document/1438090/ ...one or two mice

Visual Odometry:

http://www.instructables.com/id/ROS-Visual-Odometry/ ...on raspberry pi

https://github.com/uoip/monoVO-python ...python and opencv2

https://github.com/Transportation-Inspection/visual_odometry ...another one in python

Python Logo:

Standard python turtle graphics: from turtle import * forward(15) ...

https://stackoverflow.com/questions/4071633/python-turtle-module-saving-an-image ...a tip how to export the canvas as svg

...but none of this is what I need. I need Logo language interpreter where I can 1) simply get the drawing as png, and 2) replace the commands with robot moves

pylogo ... promising but the main project page was hacked perhaps this fork? https://github.com/gldnspud/pylogo

export PYTHONPATH=/home/bojar/notes/lego/pylogo:/home/bojar/notes/lego/pylogo/Pmw.1.3: python import pylogo.script pylogo.script.main() ... basic programs work but the for [ i ... ] syntax is not recognized

jslogo: for [l 10 80 5] [print :l] ...means 10 15 20 25 ... 80 pylogo: for "l (gen 10 80 5) [print :l] ...with my own generator: to gen :lo :hi :step make "x [] while [ :lo < (:hi+1) ] [ make "x lput :lo :x make "lo :lo + :step ] output :x end

http://www.calormen.com/jslogo/language.html ...jslogo syntax

Simpler:

https://github.com/dominoanty/Logo-Interpreter ...works but python2 and pygame needed ... and it takes 87% CPU when idle, probably due to pygame ... but does not support procedures

here: cd Logo-Interpreter python main.py repeat 10 [ lt 60 fd 20 rt 120 fd 20 lt 60 ]

Could be also used to record turtle moves from mouse drawing.

http://www.calormen.com/jslogo/ ... nice javascript interpreter, for testing, with examples source: https://github.com/inexorabletash/jslogo

Great Logo One-Liners

http://www.mathcats.com/gallery/15wordcontest.html http://www.mathcats.com/gallery/15wordcontest.html#squarespiralvariations

And other nice drawings: http://www.pool-rnd.com/en/Kafelka.aspx?artID=5

Web servers:

https://www.youtube.com/watch?v=x5VauXr7W4A ...demos the standard EV3D4: https://github.com/ev3dev/ev3dev-lang-python/tree/jessie/demo/EV3D4

Pylogo on robot:

pylogo needs tkinter which in turn needs X display. xvfb-run from xvfb resolved the limitation:

robot@ev3dev:~/lego/pylogo$ xvfb-run ./start.py ...no more complaints, so it hopefully works. (Can't see anything in xvfb...)

...well, not really sure, after killing the silent process, I got: IO: fatal IO error 11 (Resource temporarily unavailable) on X server ":99" after 1632 requests (668 known processed) with 0 events remaining.

Battery Voltage in bash

cat /sys/class/power_supply/lego-ev3-battery/voltage_now

divide by 10^6

Overloaded on Stretch

ev3dev/ev3dev#1022

top - 17:01:17 up 1:31, 3 users, load average: 3.06, 2.83, 2.59 Tasks: 73 total, 2 running, 45 sleeping, 0 stopped, 0 zombie %Cpu(s): 74.1 us, 23.7 sy, 0.0 ni, 0.0 id, 0.3 wa, 0.0 hi, 2.0 si, 0.0 st KiB Mem : 57180 total, 1532 free, 24700 used, 30948 buff/cache KiB Swap: 98300 total, 84988 free, 13312 used. 28968 avail Mem

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
2606 robot 20 0 12276 8308 4804 R 49.8 14.5 0:06.25 run_ev3.py
2348 root 20 0 0 0 0 I 14.5 0.0 1:40.79 kworker/0:0
71 root -51 0 0 0 0 S 13.8 0.0 12:25.19 irq/245-ti-+

Trying to figure out the distance needed for 360 degree tank rotation

random-bits/find_angle_speed.py

The following generally reports how much needs to be travelled with the left and right motors to get 180 degree of rotation.

The average is around 402, as detailed below. To travel 1 degree, we need to travel 402/180 steps

carpet: At 100 , travel for 1/2circ 403 L and 400 R; absL: 805 , absR: 800 At 100 , travel for 1/2circ 401 L and 399 R; absL: 1206 , absR: 1199 At 100 , travel for 1/2circ 401 L and 400 R; absL: 1607 , absR: 1599 At 100 , travel for 1/2circ 403 L and 399 R; absL: 2010 , absR: 1998 At 100 , travel for 1/2circ 401 L and 398 R; absL: 2411 , absR: 2396 At 100 , travel for 1/2circ 402 L and 399 R; absL: 804 , absR: 796 At 100 , travel for 1/2circ 404 L and 405 R; absL: 1208 , absR: 1201 At 100 , travel for 1/2circ 403 L and 398 R; absL: 1611 , absR: 1599 At 100 , travel for 1/2circ 403 L and 404 R; absL: 2014 , absR: 2003 At 100 , travel for 1/2circ 402 L and 398 R; absL: 2416 , absR: 2401 At 150 , travel for 1/2circ 405 L and 404 R; absL: 2821 , absR: 2805 At 150 , travel for 1/2circ 401 L and 398 R; absL: 3222 , absR: 3203 At 150 , travel for 1/2circ 401 L and 398 R; absL: 3623 , absR: 3601 At 150 , travel for 1/2circ 402 L and 402 R; absL: 4025 , absR: 4003 At 150 , travel for 1/2circ 403 L and 402 R; absL: 4428 , absR: 4405 At -180 , travel for 1/2circ 401 L and 404 R; absL: 4027 , absR: 4001 At -180 , travel for 1/2circ 408 L and 408 R; absL: 3619 , absR: 3593 At -180 , travel for 1/2circ 403 L and 404 R; absL: 3216 , absR: 3189 At -180 , travel for 1/2circ 403 L and 405 R; absL: 2813 , absR: 2784 At -180 , travel for 1/2circ 402 L and 405 R; absL: 2411 , absR: 2379 At 150 , travel for 1/2circ 402 L and 398 R; absL: 2813 , absR: 2777 At 150 , travel for 1/2circ 401 L and 399 R; absL: 3214 , absR: 3176 At 150 , travel for 1/2circ 401 L and 399 R; absL: 3615 , absR: 3575 At 150 , travel for 1/2circ 401 L and 401 R; absL: 4016 , absR: 3976 At 150 , travel for 1/2circ 404 L and 403 R; absL: 4420 , absR: 4379 At -90 , travel for 1/2circ 402 L and 399 R; absL: 4018 , absR: 3980 At -90 , travel for 1/2circ 403 L and 401 R; absL: 3615 , absR: 3579 At -90 , travel for 1/2circ 402 L and 400 R; absL: 3213 , absR: 3179 At -90 , travel for 1/2circ 401 L and 399 R; absL: 2812 , absR: 2780 At -90 , travel for 1/2circ 401 L and 401 R; absL: 2411 , absR: 2379 At -180 , travel for 1/2circ 403 L and 404 R; absL: 2008 , absR: 1975 At -180 , travel for 1/2circ 405 L and 409 R; absL: 1603 , absR: 1566 At -180 , travel for 1/2circ 403 L and 405 R; absL: 1200 , absR: 1161 At -180 , travel for 1/2circ 403 L and 404 R; absL: 797 , absR: 757 At -180 , travel for 1/2circ 401 L and 405 R; absL: 396 , absR: 352 At 90 , travel for 1/2circ 403 L and 401 R; absL: 799 , absR: 753 At 90 , travel for 1/2circ 401 L and 401 R; absL: 1200 , absR: 1154 At 90 , travel for 1/2circ 401 L and 398 R; absL: 1601 , absR: 1552 At 90 , travel for 1/2circ 403 L and 404 R; absL: 2004 , absR: 1956 At 90 , travel for 1/2circ 403 L and 404 R; absL: 2407 , absR: 2360 At -120 , travel for 1/2circ 402 L and 399 R; absL: 2005 , absR: 1961 At -120 , travel for 1/2circ 403 L and 399 R; absL: 1602 , absR: 1562 At -120 , travel for 1/2circ 402 L and 403 R; absL: 1200 , absR: 1159 At -120 , travel for 1/2circ 402 L and 402 R; absL: 798 , absR: 757 At -120 , travel for 1/2circ 403 L and 400 R; absL: 395 , absR: 357 At -180 , travel for 1/2circ 405 L and 408 R; absL: 10 , absR: 51 At -180 , travel for 1/2circ 405 L and 409 R; absL: 415 , absR: 460 At -180 , travel for 1/2circ 401 L and 405 R; absL: 816 , absR: 865 At -180 , travel for 1/2circ 402 L and 405 R; absL: 1218 , absR: 1270 At -180 , travel for 1/2circ 404 L and 407 R; absL: 1622 , absR: 1677 At -180 , travel for 1/2circ 401 L and 404 R; absL: 2023 , absR: 2081 At -180 , travel for 1/2circ 404 L and 407 R; absL: 2427 , absR: 2488 At -180 , travel for 1/2circ 403 L and 407 R; absL: 2830 , absR: 2895 At -180 , travel for 1/2circ 403 L and 404 R; absL: 3233 , absR: 3299

Solid floor:

At 100 , travel for 1/2circ 402 L and 399 R; absL: 804 , absR: 797 At 100 , travel for 1/2circ 406 L and 406 R; absL: 1210 , absR: 1203 At 100 , travel for 1/2circ 401 L and 400 R; absL: 1611 , absR: 1603 At 100 , travel for 1/2circ 402 L and 398 R; absL: 2013 , absR: 2001 At 100 , travel for 1/2circ 402 L and 398 R; absL: 2415 , absR: 2399 At 90 , travel for 1/2circ 402 L and 398 R; absL: 2817 , absR: 2797 At 90 , travel for 1/2circ 403 L and 401 R; absL: 3220 , absR: 3198 At 90 , travel for 1/2circ 402 L and 401 R; absL: 3622 , absR: 3599 At 90 , travel for 1/2circ 402 L and 400 R; absL: 4024 , absR: 3999 At 90 , travel for 1/2circ 402 L and 401 R; absL: 4426 , absR: 4400 At -90 , travel for 1/2circ 401 L and 397 R; absL: 4025 , absR: 4003 At -90 , travel for 1/2circ 401 L and 400 R; absL: 3624 , absR: 3603 At -90 , travel for 1/2circ 402 L and 401 R; absL: 3222 , absR: 3202 At -90 , travel for 1/2circ 401 L and 400 R; absL: 2821 , absR: 2802 At -90 , travel for 1/2circ 402 L and 399 R; absL: 2419 , absR: 2403 At 150 , travel for 1/2circ 401 L and 398 R; absL: 2820 , absR: 2801 At 150 , travel for 1/2circ 403 L and 402 R; absL: 3223 , absR: 3203 At 150 , travel for 1/2circ 404 L and 404 R; absL: 3627 , absR: 3607 At 150 , travel for 1/2circ 401 L and 398 R; absL: 4028 , absR: 4005 At 150 , travel for 1/2circ 402 L and 398 R; absL: 4430 , absR: 4403 At 120 , travel for 1/2circ 403 L and 402 R; absL: 4833 , absR: 4805 At 120 , travel for 1/2circ 403 L and 399 R; absL: 5236 , absR: 5204 At 120 , travel for 1/2circ 403 L and 398 R; absL: 5639 , absR: 5602 At 120 , travel for 1/2circ 403 L and 400 R; absL: 6042 , absR: 6002 At 120 , travel for 1/2circ 402 L and 400 R; absL: 6444 , absR: 6402 At -180 , travel for 1/2circ 404 L and 405 R; absL: 6040 , absR: 5997 At -180 , travel for 1/2circ 403 L and 408 R; absL: 5637 , absR: 5589 At -180 , travel for 1/2circ 403 L and 403 R; absL: 5234 , absR: 5186 At -180 , travel for 1/2circ 402 L and 405 R; absL: 4832 , absR: 4781 At -180 , travel for 1/2circ 404 L and 407 R; absL: 4428 , absR: 4374 At -150 , travel for 1/2circ 404 L and 401 R; absL: 4024 , absR: 3973 At -150 , travel for 1/2circ 401 L and 400 R; absL: 3623 , absR: 3573 At -150 , travel for 1/2circ 402 L and 402 R; absL: 3221 , absR: 3171 At -150 , travel for 1/2circ 401 L and 400 R; absL: 2820 , absR: 2771 At -150 , travel for 1/2circ 402 L and 400 R; absL: 2418 , absR: 2371 At 180 , travel for 1/2circ 403 L and 404 R; absL: 2821 , absR: 2775 At 180 , travel for 1/2circ 401 L and 404 R; absL: 3222 , absR: 3179 At 180 , travel for 1/2circ 404 L and 402 R; absL: 3626 , absR: 3581 At 180 , travel for 1/2circ 402 L and 404 R; absL: 4028 , absR: 3985 At 180 , travel for 1/2circ 401 L and 405 R; absL: 4429 , absR: 4390 At -180 , travel for 1/2circ 403 L and 406 R; absL: 4026 , absR: 3984 At -180 , travel for 1/2circ 402 L and 405 R; absL: 3624 , absR: 3579 At -180 , travel for 1/2circ 404 L and 409 R; absL: 3220 , absR: 3170 At -180 , travel for 1/2circ 404 L and 407 R; absL: 2816 , absR: 2763 At -180 , travel for 1/2circ 404 L and 407 R; absL: 2412 , absR: 2356 At 90 , travel for 1/2circ 401 L and 397 R; absL: 2813 , absR: 2753 At 90 , travel for 1/2circ 405 L and 405 R; absL: 3218 , absR: 3158 At 90 , travel for 1/2circ 402 L and 400 R; absL: 3620 , absR: 3558 At 90 , travel for 1/2circ 402 L and 400 R; absL: 4022 , absR: 3958 At 90 , travel for 1/2circ 403 L and 401 R; absL: 4425 , absR: 4359 At -90 , travel for 1/2circ 411 L and 408 R; absL: 4014 , absR: 3951 At -90 , travel for 1/2circ 402 L and 401 R; absL: 3612 , absR: 3550 At -90 , travel for 1/2circ 401 L and 399 R; absL: 3211 , absR: 3151 At -90 , travel for 1/2circ 403 L and 403 R; absL: 2808 , absR: 2748 At -90 , travel for 1/2circ 401 L and 399 R; absL: 2407 , absR: 2349 At -90 , travel for 1/2circ 401 L and 399 R; absL: 2006 , absR: 1950 At -90 , travel for 1/2circ 401 L and 399 R; absL: 1605 , absR: 1551 At -90 , travel for 1/2circ 401 L and 400 R; absL: 1204 , absR: 1151

...strangely, when I set these values, the robot rotated much less with run_to_rel_pos, although the tacho counters seemed to report the correct 200 of delta for 90 degrees turn:

Left -90 called, going for -201 from 20768 L, -28889 R. Left -90 done, going for -201 to 20971 L, -29090 R.

Left -90 called, going for -201 from 20570 L, -29893 R. Left -90 done, going for -201 to 20773 L, -30093 R.

Left -90 called, going for -201 from 20470 L, -30394 R. Left -90 done, going for -201 to 20674 L, -30594 R.

180 seems like 14 degrees

full circle seems like 2098

2018-05-25 Navrh zastavitelneho weboveho interpretru loga

  • webserver:
    • nabizi kod k editaci [done]
    • pri stisku preview to vrati nakreslene SVG (nebo error log) [done]
    • po uspesnem preview je mozne spustit kod [done]
    • propagace stavu robota do webu, aby se vedelo, jestli je mozny run nebo stop
    • tlacitko na robotovi udela stop
    • kdyz vyjede mimo bile, udela stop
    • infra se da jezdit nezavisle, ale smysl to ma jen, kdyz to nic nemaluje [done]

Now the basic things work:

cd loev3go
./run_webserver.py [--no-robot]

TODO:

  • stav baterky
  • prepinac dry-run, aby obrazek projel bez pokladani pera [done]
  • stop_motors nejak otoci polaritu, zkousim tedy pridat reset .... fixed, ale je prohozeny levy a pravy motor ... pero je spravne leve je cerne a je to LEFT
  • speed choice in logo code ("speed 200") [done]
  • motor polarity (jezdi pozadu) [done]
  • ladici robot, tj. jako ev3dev, ale jen ladici vypisy, aby se testovalo zastavovani ap. [done]
  • web-based "pen release" and "pen fix" (staci jedna vec: stop_motors, clovek ji zmackne jednou, nastavi vypnuta pera, zmackne podruhe, aby zresetoval stav, musi se asi taky zmenit stav na PEN_UP
  • IR-follow
  • left and right pens are swapped [done]
  • inaccuracies:
    • should wait after pendown, this is critical!
    • dangerous are also rotations there and immediately back
    • the 20 degrees themselves are probably OK
    • unclear that the squares seem sort of OK and the rotation by 20 degrees between each red or black square does not add up 9202 = 360
      • should check level of shaking due to pen movements, once we have mouse in
      • should check non-linearity of robot rotation, perhaps 90 degrees work well but 20 do not.

Code to check the non-linearity of rotation: ... first a circle in one color, then a circle of alternating colors penwidth 2 pencolor "right pd repeat 18 [ fd 10 lt 20 ] rt 180 repeat 9 [ pencolor "right fd 10 lt 20 pencolor "left fd 10 lt 20 ]

Setting up robot as wifi accesspoint

Maybe this tip contains everything that is needed:

https://superuser.com/questions/748455/how-to-setup-access-point-wifi-hotspot-on-debian https://superuser.com/questions/437137/how-to-turn-my-linux-netbook-into-wifi-ap

Tips for power supply

https://www.philohome.com/nxtsupply/nxtsupply.htm ...napajeni ze site

https://zbozi.mobilmania.cz/ostatni-baterie-a-prislusenstvi/napajeci-adapter-230v-3-12v-600ma/ ...194Kc https://www.softcom.cz/eshop/napajeci-adapter-230v-3-12v-stejnosmerny-600ma_d107596.html

Bootstrap web layout

https://getbootstrap.com/docs/3.3/css/

Switch off color sensor

switch it off

echo other-uart > /sys/class/lego-port/port1/mode

and back on

echo auto > /sys/class/lego-port/port1/mode

Nice figures:

jewels:

penwidth 2 to square repeat 4 [ fd 10 rt 90 ] end repeat 9 [ pencolor "left pd square pu fd 10 lt 20 pencolor "right pd square pu fd 10 lt 20 ]

Colors of carpet etc

v seru v zelenem pokoji:

tmavy kusovy koberec: Sum: 68, Red: 28, Green: 34, Blue: 6

bily papir Sum: 616, Red: 233, Green: 259, Blue: 124

cara na bilem papire: Sum: 588, Red: 221, Green: 248, Blue: 119

svetly zeleny koberec: Sum: 182, Red: 76, Green: 82, Blue: 24

koberec v obyvaku: svetly bod: Sum: 78, Red: 42, Green: 29, Blue: 7 tmavsi cast: Sum: 35, Red: 18, Green: 13, Blue: 4 Sum: 24, Red: 11, Green: 10, Blue: 3 Sum: 9, Red: 3, Green: 4, Blue: 2 nejtmavsi cast: Sum: 12, Red: 4, Green: 5, Blue: 3 svetla cast koberce: Sum: 111, Red: 56, Green: 44, Blue: 11

bily papir ve svetle v obyvaku: Sum: 582, Red: 222, Green: 247, Blue: 113

a hneda caranice na nem: Sum: 254, Red: 117, Green: 97, Blue: 40

Mouse in USB hub:

Mouse devices: /dev/input/by-id/usb-13ba_Barcode_Reader-if01-event-mouse

15:30 [644] random-bits$./report-mouse-moves.py Device: Barcode Reader D: device /dev/input/event3, name "Barcode Reader ", phys "usb-ohci-da8xx-1.4/input1" Device: Barcode Reader D: device /dev/input/event2, name "Barcode Reader ", phys "usb-ohci-da8xx-1.4/input0" Device: EV3 Brick Buttons D: device /dev/input/event1, name "EV3 Brick Buttons", phys "gpio-keys/input0" Device: LEGO MINDSTORMS EV3 Speaker D: device /dev/input/event0, name "LEGO MINDSTORMS EV3 Speaker", phys ""

Which old sets I used to have:

6932 Futuron 6750 Sonic Robot

6780 ... possibly, but quite unsure https://brickset.com/sets/6783-1 ...rather not

Slowness:

ev3dev/ev3dev#1199 ...IR sensor contact? ...IR sensor in wrong port?

Strange random segfaults

00:16 obonb ~$ssh robot@robot Linux ev3dev 4.14.38-ev3dev-2.0.1-ev3 #1 PREEMPT Sat May 5 13:15:45 CDT 2018 armv5tejl _____ _ _____ |__ / | | _____ __ / _ \ \ / / | \ / ` |/ _ \ \ / / | __/\ V / ) | (| | /\ V / _| _/ |/ _,_|__| _/

Debian stretch on LEGO MINDSTORMS EV3! Last login: Mon Feb 3 23:09:29 2020 from 192.168.10.110 05:30 [734] ~$sudo apt-get update [sudo] password for robot: Hit:1 http://security.debian.org stretch/updates InRelease
Ign:2 http://httpredir.debian.org/debian stretch InRelease
Hit:3 http://httpredir.debian.org/debian stretch Release
Hit:4 http://archive.ev3dev.org/debian stretch InRelease
Reading package lists... Done
awk: cmd. line:1: fatal error: internal error: segfault Aborted 05:35 [728] ~$sudo apt-get install --reinstall awk Reading package lists... Done Building dependency tree
Reading state information... Done Package awk is a virtual package provided by: original-awk 2012-12-20-6 mawk 1.3.3-17+b3 gawk 1:4.1.4+dfsg-1 You should explicitly select one to install.

E: Package 'awk' has no installation candidate 05:36 [728] ~$sudo apt-get install --reinstall gawk Reading package lists... Done Building dependency tree
Reading state information... Done 0 upgraded, 0 newly installed, 1 reinstalled, 0 to remove and 184 not upgraded. Need to get 0 B/533 kB of archives. After this operation, 0 B of additional disk space will be used. (Reading database ... 49440 files and directories currently installed.) Preparing to unpack .../gawk_1%3a4.1.4+dfsg-1_armel.deb ... Unpacking gawk (1:4.1.4+dfsg-1) over (1:4.1.4+dfsg-1) ... Setting up gawk (1:4.1.4+dfsg-1) ... 05:39 [728] ~$sudo apt-get install strace Reading package lists... Done Building dependency tree
Reading state information... Done The following NEW packages will be installed: strace 0 upgraded, 1 newly installed, 0 to remove and 184 not upgraded. Need to get 478 kB of archives. After this operation, 854 kB of additional disk space will be used. Get:1 http://httpredir.debian.org/debian stretch/main armel strace armel 4.15-2 [478 kB] Fetched 478 kB in 2s (189 kB/s) Selecting previously unselected package strace. (Reading database ... 49440 files and directories currently installed.) Preparing to unpack .../strace_4.15-2_armel.deb ... Unpacking strace (4.15-2) ... Setting up strace (4.15-2) ... awk: cmd. line:1: (FILENAME=- FNR=1) fatal: field.c:111: erealloc called with zero bytes 05:44 [724] ~$sudo apt-get install memtester eading package lists... Done Building dependency tree
Reading state information... Done The following NEW packages will be installed: memtester 0 upgraded, 1 newly installed, 0 to remove and 184 not upgraded. Need to get 18.7 kB of archives. After this operation, 45.1 kB of additional disk space will be used. Get:1 http://httpredir.debian.org/debian stretch/main armel memtester armel 4.3.0-4+b1 [18.7 kB] Fetched 18.7 kB in 1s (12.5 kB/s)
Selecting previously unselected package memtester. (Reading database ... 49449 files and directories currently installed.) Preparing to unpack .../memtester_4.3.0-4+b1_armel.deb ... Unpacking memtester (4.3.0-4+b1) ... Setting up memtester (4.3.0-4+b1) ... 05:49 [725] ~$memtester 1024 5 -bash: memtester: command not found 05:50 [723] ~$sudo memtester 1024 5 memtester version 4.3.0 (32-bit) Copyright (C) 2001-2012 Charles Cazabon. Licensed under the GNU General Public License version 2 (only).

pagesize is 4096 pagesizemask is 0xfffff000 want 1024MB (1073741824 bytes) got 121MB (127242240 bytes), trying mlock ...Killed awk: cmd. line:1: fatal error: internal error: segfault Aborted ter version 4.3.0 (32-bit) Copyright (C) 2001-2012 Charles Cazabon. Licensed under the GNU General Public License version 2 (only).

pagesize is 4096 pagesizemask is 0xfffff000 want 30MB (31457280 bytes) got 30MB (31457280 bytes), trying mlock ...locked. Loop 1/2: Stuck Address : ok
Random Value : ok Compare XOR : ok Compare SUB : ok Compare MUL : ok Compare DIV : ok Compare OR : ok Compare AND : ok Sequential Increment: ok Solid Bits : ok
Block Sequential : setting 200^C supoawk: cmd. line:1: (FILENAME=- FNR=1) warning: gensub: third argument 0 treated as 1 awk: cmd. line:1: (FILENAME=- FNR=1) warning: gensub: third argument 0 treated as 1

strace: bugs/strace-test-python-tk-segfaulting.stderr

top dies with segfault:

07:55 [822] ~$cat /proc/meminfo MemTotal: 57180 kB MemFree: 6244 kB MemAvailable: 36932 kB Buffers: 4700 kB Cached: 27764 kB SwapCached: 1624 kB Active: 15376 kB Inactive: 20744 kB Active(anon): 2308 kB Inactive(anon): 1360 kB Active(file): 13068 kB Inactive(file): 19384 kB Unevictable: 0 kB Mlocked: 0 kB SwapTotal: 98300 kB SwapFree: 89340 kB Dirty: 4 kB Writeback: 0 kB AnonPages: 3076 kB Mapped: 12332 kB Shmem: 12 kB Slab: 6172 kB SReclaimable: 1692 kB SUnreclaim: 4480 kB KernelStack: 552 kB PageTables: 680 kB NFS_Unstable: 0 kB Bounce: 0 kB WritebackTmp: 0 kB CommitLimit: 126888 kB Committed_AS: 103200 kB VmallocTotal: 966656 kB VmallocUsed: 0 kB VmallocChunk: 0 kB

07:56 [822] ~$top Segmentation fault

Failing to apt-get: 07:42 [835] ~$sudo apt-get install --reinstall libtk8.6 tk8.6-blt2.5 [sudo] password for robot: Reading package lists... Done Building dependency tree
Reading state information... Done 0 upgraded, 0 newly installed, 2 reinstalled, 0 to remove and 184 not upgraded. Need to get 0 B/1,156 kB of archives. After this operation, 0 B of additional disk space will be used. (Reading database ... 49459 files and directories currently installed.) Preparing to unpack .../libtk8.6_8.6.6-1+b1_armel.deb ... Unpacking libtk8.6:armel (8.6.6-1+b1) over (8.6.6-1+b1) ... Preparing to unpack .../tk8.6-blt2.5_2.5.3+dfsg-3_armel.deb ... Unpacking tk8.6-blt2.5 (2.5.3+dfsg-3) over (2.5.3+dfsg-3) ... Setting up libtk8.6:armel (8.6.6-1+b1) ... Processing triggers for libc-bin (2.24-11+deb9u3) ... Setting up tk8.6-blt2.5 (2.5.3+dfsg-3) ... Processing triggers for libc-bin (2.24-11+deb9u3) ... awk: cmd. line:1: fatal error: internal error: segfault Aborted

Memory was not full, I do not see much change in: (when apt-get was already stopped) 07:44 [831] ~$cat /proc/meminfo MemTotal: 57180 kB MemFree: 2008 kB MemAvailable: 36616 kB Buffers: 5740 kB Cached: 30644 kB SwapCached: 1780 kB Active: 18940 kB Inactive: 21460 kB Active(anon): 1676 kB Inactive(anon): 2364 kB Active(file): 17264 kB Inactive(file): 19096 kB Unevictable: 0 kB Mlocked: 0 kB SwapTotal: 98300 kB SwapFree: 89340 kB Dirty: 0 kB Writeback: 0 kB AnonPages: 3344 kB Mapped: 13928 kB Shmem: 24 kB Slab: 6208 kB SReclaimable: 1716 kB SUnreclaim: 4492 kB KernelStack: 552 kB PageTables: 680 kB NFS_Unstable: 0 kB Bounce: 0 kB WritebackTmp: 0 kB CommitLimit: 126888 kB Committed_AS: 103200 kB VmallocTotal: 966656 kB VmallocUsed: 0 kB VmallocChunk: 0 kB

08:07 [814] ~$sudo apt-get install --reinstall procps Reading package lists... Done Building dependency tree
Reading state information... Done The following packages will be upgraded: procps 1 upgraded, 0 newly installed, 0 to remove and 183 not upgraded. Need to get 244 kB of archives. After this operation, 0 B of additional disk space will be used. Get:1 http://httpredir.debian.org/debian stretch/main armel procps armel 2:3.3.12-3+deb9u1 [244 kB] Fetched 244 kB in 1s (152 kB/s)
(Reading database ... 49459 files and directories currently installed.) Preparing to unpack .../procps_2%3a3.3.12-3+deb9u1_armel.deb ... Unpacking procps (2:3.3.12-3+deb9u1) over (2:3.3.12-3) ... Setting up procps (2:3.3.12-3+deb9u1) ... Processing triggers for systemd (232-25+deb9u2) ... topawk: cmd. line:1: fatal error: internal error: segfault Aborted 08:09 [813] ~$top

signal 11 (SEGV) was caught by top, please
see http://www.debian.org/Bugs/Reporting

Segmentation fault

...it is not bad blocks: On main machine: /dev/mmcblk0p2 3785840 2493144 1105064 70% /media/bojar/EV3DEV_ROOTFS /dev/mmcblk0p1 49038 7322 41716 15% /media/bojar/EV3DEV_BOOT 09:35 obonb ~$sudo umount /media/bojar/EV3DEV_ROOTFS [sudo] password for bojar: 09:35 obonb ~$sudo umount /media/bojar/EV3DEV_BOOT 09:35 obonb ~$badblocks -n -v /dev/mmcblk0p1 badblocks: Permission denied while trying to determine device size 09:35 obonb ~$sudo badblocks -n -v /dev/mmcblk0p1 Checking for bad blocks in non-destructive read-write mode From block 0 to 49151 Testing with random pattern: Pass completed, 0 bad blocks found. (0/0/0 errors) 09:36 obonb ~$sudo badblocks -n -v /dev/mmcblk0p2 Checking for bad blocks in non-destructive read-write mode From block 0 to 3878911 Testing with random pattern: Pass completed, 0 bad blocks found. (0/0/0 errors)

...I filed an issue on this: ev3dev/ev3dev#1374

Other good links: http://www.legoengineering.com/ev3-gone-wrong/