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by amcdonley
Fri Jun 14, 2019 2:49 pm
Forum: Automation, sensing and robotics
Topic: How to maximize Robot Play Time - NiMH Batteries?
Replies: 6
Views: 964

Re: How to maximize Robot Play Time - NiMH Batteries?

BAck to basics. There are only four possible problems here; 1. The charger is not doing its job 2. The battery pack is faulty and not holding a charge 3. The robot is using more power than expected 4. The Juice data is bullshit. I suspect you either have a dodgy charge situation, or a bad cell in t...
by amcdonley
Thu Jun 13, 2019 7:02 pm
Forum: Automation, sensing and robotics
Topic: How to measure distance with the raspberry pi camera
Replies: 4
Views: 3285

Re: How to measure distance with the raspberry pi camera

For a PiCamera fixed to a bot with a fixed/known pointing angle, the distance to the bottom line of the image is a known, fixed number. I have a PiCam v1.3 on my bot: 5MP 1080p30 2592 x 1944 pixels 35mm focal length equiv. focus 1 m to inf. H 53 deg x V 41 deg f/2.9 (Use 1296 x 976 and 2x2 binning f...
by amcdonley
Thu Jun 13, 2019 6:34 pm
Forum: Automation, sensing and robotics
Topic: irritating battery limits
Replies: 21
Views: 2187

Re: irritating battery limits - this works for my bot

A subject dear to my heart, this is - how to recharge a robot without shutting it down? (In my case because the bot has no wakeup timer function.) Carl Recharging On His Dock.jpg How I solved it for my GoPiGo3 robot: 1) Eight 2800mAh NiMH AA-cells (series connected) 2) Twin pigtails in parallel off ...
by amcdonley
Thu Jun 13, 2019 4:38 pm
Forum: Automation, sensing and robotics
Topic: How to maximize Robot Play Time - NiMH Batteries?
Replies: 6
Views: 964

How to maximize Robot Play Time - NiMH Batteries?

My question: how to maximize "play time" for my robot? I have been using EBL NiMH rechargeable batteries in my Raspberry Pi robots for the last five years, originally six 5000mAh C-cells, and for the last year - eight 2800mAh AA-cells in my GoPiGo3 robot Carl. My robot charges the eight AA...
by amcdonley
Thu May 02, 2019 4:13 am
Forum: Raspberry Pi Desktop for PC and Mac
Topic: geekbench4 file not found weirdness
Replies: 4
Views: 739

Re: geekbench4 file not found weirdness

fruitoftheloom wrote:
Wed May 01, 2019 3:48 pm

Pixel Desktop was renamed nearly 2 years ago:

...

Regards x86-64 64bit version, there has never been a release ...
Great info - thanks.

I'm certainly not hampered by the 32-bit version in any way. At least now I understand the reasons. Double thanks.
by amcdonley
Thu Apr 25, 2019 2:18 am
Forum: Raspberry Pi Desktop for PC and Mac
Topic: geekbench4 file not found weirdness
Replies: 4
Views: 739

Re: geekbench4 file not found weirdness

From https://www.geekbench.com/download/linux/ : System Requirements Ubuntu 14.04 LTS or later 2GB of RAM Perhaps they really do mean ' Ubuntu ', and not just some similar-looking Debian-based Linux distribution? Apparently. I guess I was lucky that the 32bit version ran. Interestingly, my score wa...
by amcdonley
Tue Apr 23, 2019 2:43 pm
Forum: Raspberry Pi Desktop for PC and Mac
Topic: RPi Desktop x86 Canon Printer Installation Problem
Replies: 5
Views: 1185

Re: RPi Desktop x86 Canon Printer Installation Problem

I'm stuck on this same issue (a year later) with the 11 Apr 2019 X86 Debian 9 with PIXEL desktop for PC and a Canon MX860 printer.

Agree that this is not a PIXEL desktop issue. Posting here in case anyone has found a solution.
by amcdonley
Tue Apr 23, 2019 2:38 pm
Forum: Raspberry Pi Desktop for PC and Mac
Topic: geekbench4 file not found weirdness
Replies: 4
Views: 739

geekbench4 file not found weirdness

I am running Geekbench-4.3.3-Linux on (uname -a): Linux AlanLaptop 4.9.0-8-amd64 #1 SMP Debian 4.9.144-3.1 (2019-02-19) x86_64 GNU/Linux (Raspberrypi.org X86 Debian with RaspberryPi (formerly PIXEL) desktop for PC 11Apr2019) on a Toshiba Portege Z935 with 5.73GB memory Toshiba Version 6.80 BIOS, Int...
by amcdonley
Thu Aug 30, 2018 12:00 pm
Forum: Automation, sensing and robotics
Topic: NiMH Batteries - Selecting Safe Shutdown Limit
Replies: 5
Views: 881

Re: NiMH Batteries - Selecting Safe Shutdown Limit

The risk with multiple NiMH cells in series is that their capacities are or become different enough such that (because of the "cliff edge") one cell reaches zero while the others still have sufficient voltage that the powered circuit continues to operate and draw current. Operation with c...
by amcdonley
Thu Aug 30, 2018 11:37 am
Forum: Automation, sensing and robotics
Topic: NiMH Batteries - Selecting Safe Shutdown Limit
Replies: 5
Views: 881

Re: NiMH Batteries - Selecting Safe Shutdown Limit

... Set that too high, and [it] wouldn't run long enough on one charge; set it too low and the life of the battery was compromised, so ...set it to ... 1.1v cut-off So along came some cowboys, ... cut-off became 1.0v. ... life of the pack was reduced, ... almost no extra run-time, because of the cl...
by amcdonley
Thu Aug 30, 2018 12:38 am
Forum: Automation, sensing and robotics
Topic: NiMH Batteries - Selecting Safe Shutdown Limit
Replies: 5
Views: 881

NiMH Batteries - Selecting Safe Shutdown Limit

I just built a new bot based on the GoPiGo3 platform and need to select a safe shutdown voltage limit. * I am using 8 AA size 2300 mAH NiMH cells and a Tenergy multi-voltage peaking charger. * (The GoPiGo3 has a get_battery_voltage() function which returns a value which is 0.6v less than the actual...
by amcdonley
Thu Jul 05, 2018 12:05 pm
Forum: Troubleshooting
Topic: sudo apt-get update uses IPv6 - have to force IPv4 to succeed
Replies: 4
Views: 2891

Re: sudo apt-get update uses IPv6 - have to force IPv4 to succeed

Just a thought: what happens if you use Google DNS server?
by amcdonley
Wed Dec 20, 2017 7:55 pm
Forum: General discussion
Topic: Boinc not working after upgrade to Stretch
Replies: 2
Views: 675

Re: Boinc not working after upgrade to Stretch

I had to do the same thing twice after early Stretch updates. Did an update this week that did not affect my BOINC.
by amcdonley
Fri Dec 15, 2017 5:32 pm
Forum: Troubleshooting
Topic: Debugging Motion and the Raspberry Pi Camera
Replies: 1
Views: 1288

Re: Debugging Motion and the Raspberry Pi Camera

This worked for me this morning: Motion for Raspberry Pi sudo modprobe bcm2835-v4l2 sudo /etc/modules to add: # camera with v4l2 driver bcm2835-v4l2 reboot sudo apt-get install motion sudo cp /etc/motion/motion.conf /etc/motion/motion.conf.bak sudo nano /etc/motion/motion.conf to change: rotate 180 ...
by amcdonley
Fri Dec 15, 2017 12:12 am
Forum: Troubleshooting
Topic: RPi3 WiFi interference?
Replies: 0
Views: 409

RPi3 WiFi interference?

Anecdotally, when I have two RPi3 on the same subnet (10.0.0.x on US channel 6), or even same subnet, different WiFi networks (SSID1 and SSID2 in same room, two routers on different channels - US 3 and US 6) I often see: sudo apt-get update Ign:1 http://archive.raspberrypi.org/debian stretch InRelea...
by amcdonley
Tue Nov 28, 2017 1:30 am
Forum: Troubleshooting
Topic: Solved: After rpi-update my robot can't feel his toes
Replies: 3
Views: 585

Re: Solved: After rpi-update my robot can't feel his toes

Why did you use rpi-update? It's not recommended for casual users. I was warned "Or for the brave and foolhardy", in a suggestion in response to my Pi3 built-in WiFi frustrations. If you are giving feedback for experimental software then you'll need to provide much more information than '...
by amcdonley
Tue Nov 28, 2017 12:12 am
Forum: Troubleshooting
Topic: Solved: After rpi-update my robot can't feel his toes
Replies: 3
Views: 585

Solved: After rpi-update my robot can't feel his toes

After I did an rpi-update this morning, my robot couldn't move and felt weak (no motor PWM and couldn't SPI to the Analog Digital Converter ). I reverted the firmware and my robot feels much better again. This one works: uname -a: Linux RWPi 4.9.41-v7+ #1023 SMP Tue Aug 8 16:00:15 BST 2017 armv7l GN...
by amcdonley
Mon Nov 27, 2017 11:58 am
Forum: Troubleshooting
Topic: Pi3 onboard Wifi: Ping Request timeouts
Replies: 6
Views: 2889

Re: Pi3 onboard Wifi: Ping Request timeouts

Run this sudo apt update && sudo apt -y dist-upgrade && sudo reboot Or for the brave and foolhardy sudo rpi-update && sudo reboot The following packages will be upgraded: libsmbclient libwbclient0 samba-common samba-libs 4 upgraded, 0 newly installed, 0 to remove and 0 not u...
by amcdonley
Mon Nov 27, 2017 10:55 am
Forum: Troubleshooting
Topic: Pi3 onboard Wifi: Ping Request timeouts
Replies: 6
Views: 2889

Re: Pi3 onboard Wifi: Ping Request timeouts

DougieLawson wrote:
Mon Nov 27, 2017 8:08 am
What kernel version are you running?
uname -a:

Linux RWPi 4.9.41-v7+ #1023 SMP Tue Aug 8 16:00:15 BST 2017 armv7l GNU/Linux

vcgencmd version:
Aug 8 2017 12:05:45
Copyright (c) 2012 Broadcom
version 196063438d7bb0769861c86f948ae653727adb7e (clean) (release)
by amcdonley
Sat Nov 25, 2017 3:04 pm
Forum: Advanced users
Topic: Disable power management in Stretch
Replies: 12
Views: 59787

Re: Disable power management in Stretch

added to /etc/rc.local: iwconfig wlan0 power off resulted in my Stretch Pi3 onboard wifi power management being permanently off. For my robot, this reduces the tx excessive retries by a factor of 10, and incoming ping Request timeouts by a factor of 2. Linux RWPi 4.9.41-v7+ #1023 SMP Tue Aug 8 16:00...
by amcdonley
Fri Nov 24, 2017 10:08 pm
Forum: Troubleshooting
Topic: Second SD card went read-only - Is shutdown -h now safe?
Replies: 3
Views: 1085

Second SD card went read-only - Is shutdown -h now safe?

Recently my robot suffered its second "read-only" SD card failure. At the moment, if my robot detects that it only has a few minutes of life left, it executes an os.system( "sudo shutdown -h now") Is shutdown -h now safe to issue? The robot launches several Python processes to ma...
by amcdonley
Fri Nov 24, 2017 9:12 pm
Forum: Troubleshooting
Topic: Pi3 onboard Wifi: Ping Request timeouts
Replies: 6
Views: 2889

Pi3 onboard Wifi: Ping Request timeouts

My robot has a (new) Pi3 running updated Raspbian Stretch, with a remote ssh session over wlan0, and a Python2.7 multi-process sensor status loop running, with a 15 minute top load of 0.10 When I ping the bot via WiFi, I see about 10 "Request timeout for icmp_seq x" per hour. With power ma...
by amcdonley
Thu Nov 09, 2017 2:23 pm
Forum: Troubleshooting
Topic: Green LED blinks 30 times on shutdown
Replies: 5
Views: 1033

Re: Green LED blinks 30 times on shutdown

RaTTuS wrote:
Thu Nov 09, 2017 12:40 pm
I suspect your wiring ;-p
For sure, my wiring is known to be weird. The robot's, on the other hand, ...
by amcdonley
Thu Nov 09, 2017 12:38 pm
Forum: Troubleshooting
Topic: Green LED blinks 30 times on shutdown
Replies: 5
Views: 1033

Re: Green LED blinks 30 times on shutdown

Not normal Thanks. And for all your assistance in chasing the WiFi issue. I ordered up a new Pi3. This is the second Pi, out of four, my robot has messed up. I keep trying to enable it to be more capable, but it seems to be resisting artificial intelligence. (It began “life” 18 years ago with 32k o...
by amcdonley
Thu Nov 09, 2017 11:37 am
Forum: Troubleshooting
Topic: Green LED blinks 30 times on shutdown
Replies: 5
Views: 1033

Green LED blinks 30 times on shutdown

I have been used to waiting for the 10 blinks on shutdown of jessie-lite. I'm on "full" stretch now, and seeing the green LED flash 30 times on shutdown. Is this the new normal, or has my Pi gained consciousness and is trying to tell me not to shut it off?

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