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Ultimate running companion

Eliminate everything but the running part.

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Need a way to carry your junk, get video of your running form, pace your workouts, light your path, play music?

When it was introduced in 2013, it was a modified G-buggy no-one cared about. 3 years later, it was still no more than an RC car, but self driving car startups saw their valuations explode & anyone in Silicon Valley who saw this machine suddenly wanted to write a $65 million check. Should have really driven it down Sand Hill Rd & fielded buyout offers.

The key development was the remote control.


The object of the robot is manetaining a constant speed & heading on its own.  This is just automated enough for a lion to drive it with 1 paw while doing something else.  The journey began in Jan 2014, with a $40 G-Buggy the lion kingdom got for free.


This was the seed of the idea.  The lion kingdom would probably have never developed the complete robot if it wasn't for the original free G buggy.

It was a very poor at setting a pace, couldn't carry cargo, but could carry a camera.  The potential for documenting runs was there.  There was no easy way to measure speed & the steering was binary.  With enough tuning however, the steering could be made proportional enough to hold a heading.  

The steering mechanism was an interesting reduction of a servo into a spring that centered the wheels & a clutch plate that applied a steering force proportional to the speed of a motor.   The controller it came with could only do binary steering, but with a fast rate sensor & feedback loop, the steering could be made somewhat proportional. 

The inner clutch plate & outer ring it pressed against while spinning, but not while stationary.

With a constant voltage applied to the traction motor, it achieved poor speed regulation but infinitely better than lions trying to pace themselves.  

The final form of the 1st model.

Several models came afterwards, as budgets increased, culminating in the Tamiya Lunchbox.   The steering was finally proportional & the speed could finally be regulated.

Attempts to make it self driving all failed, for reasons startups are too familiar with.  

Key to making it all work was a paw controller.  Proportional steering & throttle would be nice, but weight & durability dictated binary tact buttons.  China simply never made a durable, compact, proportional sensor.

The  final design had 2 buttons for slow steering, 2 buttons for fast steering, 1 button for throttle.  This was proportional enough for all needs, with the computer automating speed & heading.  1 switch controlled reverse.

The stick was further refined with 900Mhz frequency hopping radios, 4" packing tape to insulate the switches from sweat.

The current system is a modified lunchbox with a very large container.

Suspension was lowered.  Wheels were reinforced.  Tires were wrapped in nylon. 

Current mail order parts which have yielded the best results, after thousands of miles:



bearings    https://www.amazon.com/gp/slredirect/picassoRedirect.html/ref=pa_sp_atf_aps_sr_pg1_1?ie=UTF8&adId=A07934293L95IQDPPTPD4&url=https%3A%2F%2Fwww.amazon.com%2FTamiya-Lunchbox-Precision-Bearing-Rubber%2Fdp%2FB00V1QZ86S%2Fref%3Dsr_1_1_sspa%3Fie%3DUTF8%26qid%3D1549922090%26sr%3D8-1-spons%26keywords%3Dtamiya%2Blunchbox%2Bparts%26psc%3D1&qualifier=1549922089&id=4383766425134616&widgetName=sp_atf    10.48

Lunchbox kit    https://www.amazon.com/Tamiya-TMYTAM58347-1-12-Lunchbox/dp/B000BMVIGW/ref=sr_1_3?ie=UTF8&qid=1549922090&sr=8-3&keywords=tamiya+lunchbox+parts    147.2

motor    https://www.hobbypartz.com/96m276-2848-2400kv-16t.html discontinued

1:10 2400kv size 540 35mm diameter 3.17mm shaft.  The 2848 descriptor is not reliable.

bec    https://hobbyking.com/en_us/turnigy-5a-8-40v-sbec-for-lipo.html    6.86

Brushless servo    https://hobbyking.com/en_us/trackstar-ts-940hg-brushless-digital-helical-gear-high-torque-servo-25kg-0-1sec-72g.html    50

battery  ...

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  • Robo Rudulf year 2

    lion mclionhead12/23/2019 at 01:08 0 comments

    The decorations keep getting better, with the discovery of brown pipe cleaners at Hobby Lobby & the order of giant red LEDs for the LED animation.

  • Refurbing vehicle 1 & phone holster tweeking

    lion mclionhead11/30/2019 at 05:38 0 comments

    After 6 months, it was time again.  The transmission was dry & just lubed instead of rebuilt.  Other changes were lowering the front suspension to try to shorten the steering pushrods, grinding out access ways to more easily remove the transmission.

    The battery compartment got taller standoffs to make room for puffing.

    The struts got washers to prevent indentation.

    Wheels got aluminum knuckles & the pushrods had to be realigned again.  Some attempts were made to try to improve the steering, but the right wheel needs a custom pushrod to do the job.

    Green & blue were the same alignment.  Orange was toed out.  Yellow was toed in.  There's no way both toing out & in could give lower power usage than the start.  All of them were within the error bounds.  Hopefully, it just means lions are good enough at aligning by eye that they didn't need any pushrod adjustments.  Noticed the uphill direction was more variable because it was going into the wind.

    Electronicals got some hot glue for strain relief.

    Phone got some hot glue to try to stop the scratching.

    With velcro busted, it was time for a magnet wrapped in suede.  Plastic falls apart very quickly & scratches the phone.  The hope is an entire holster made of suede, but it's quite heavier than plastic.

    Notice all the LEDs got the zip tie treatment.  This has worked best for LED mounting.

    The mane concern is the hot glue coming undone.

  • Steering failure

    lion mclionhead10/15/2019 at 05:07 0 comments


    It broke after only 6 months. The only replacement part is the fabled Tamiya Shaft Bag 58347, long out of production. There are aluminum ones in China with a 6 week waiting time.  Lacking any replacement parts, the lion kingdom attempted a teflon repair. The bolt isn't long enough to reach through the teflon. Teflon is softer than the original nylon.


    During this process, it became clear the steering rods could be 1 hole shorter, so the wheels would have to be realigned for the teflon repair & aligned again next year when the China shipment arrived. All this wheel alignment had the lion kingdom searching for a better way. Lions traditionally aligned the wheels by driving a mile, recharging the battery, & measuring the charge. The charge depended on the wheel alignment as well as the battery temperature & how charged it was yesterday.


    The ideal way is to drive a certain distance & record the PWM, but this requires a constant battery voltage. A Rudeng/RIDEN voltage regulator is still the ideal solution for getting a portable, constant voltage. Getting one is another 6 week China shipment.

    It was while searching for a voltage regulator that lion kingdom realized this was what Sparkfun sold, 15 years ago. What did Sparkfun sell nowadays? Dumbed down educational kits for large schools, big ticket items for corporations, & some standard connectors. Their power supply offerings where now the laptop bricks office supply stores sold 20 years ago instead of the bare boards they used to sell.

    Exotic parts for starving college students & programmers are now only available in China. There's no money to be made in exotic parts just for building other things, partly because Chinese aren't allowed to use imported hardware in their own products.

    A Rudung was sacrificed.  The lion kingdom can remember no time when it needed 2 power supplies simultaneously.  They were only used for remembering different settings or having different connectors.  Manely, they were hoping for a future need that never came.

    The new butter surprise created a stable 9V from a 12V battery.  It had a 0.5V dropout.

    Subjectively, the results were more realistic than without a regulated voltage.  There was a steep drop in PWM for the 1st turns, then a leveling off.  Finer precision was still a matter of complete drives & measuring charge.


    The 1st 9.2 mile drive burned 246mAh/mile.  





  • Tire adhesive

    lion mclionhead09/28/2019 at 07:42 0 comments

    Lions run in hotter conditions than they did before. The wheels tend to spin inside the tires. When it's hot, the tires expand & they never move. The 1st attempt was hot gluing the tires on. That failed. The 2nd attempt was rubber cementing them on. The next attempt will be epoxy resin. The ideal adhesive would be tree sap.

    After 34 miles of hard stop & go driving, the rubber cement was still holding.  The motor definitely cogs more when the tires don't slip.

  • Button & switch failures

    lion mclionhead09/02/2019 at 03:08 0 comments

    So the throttle switch failed on, on the 900Mhz vehicle.  The 400Mhz vehicle which was modified had no further problems.  The stronger pullup resistor & lamination of the switch would have to be done to the 900Mhz vehicle.

    The next problem was the steering buttons.  These have to be replaced every year.  They got some life extension through  wrapping in packing tape.  The last wear comes from sweat which manages to get around the packing tape, holes in the packing tape, & the amount of abuse.  They's constantly banged for minor steering adjustments.  Eventually, getting good contact requires pressing the buttons sideways.  Later on, they lose their springiness.  

    Attempts to make the steering buttons more tactile involved making the center buttons closer together.  This provided clues as to what buttons were in the center., but it meant they couldn't be pressed sideways.  A new idea is to space all the buttons enough to press them sideways, while grinding the buttons at different angles to indicate which button they are.  

  • sweat + switches don't mix

    lion mclionhead08/12/2019 at 02:55 0 comments

    The same throttle switch had been used for many thousands of miles, since it was built in 2015.  It gradually started failing on, when the lion got real sweaty.  It finally failed hard & drove into an intersection on its own.  When that happens, you can either kill the transmitter & wait 1 second for the watchdog timer to stop the motor, flip it into reverse, or steer it into a curb.  The fastest move is to steer it into a curb.  For the 2nd time in uncontrolled drives into roads, there happened to be no traffic.  It's a good example of the kind of durability required in an electric scooter.

    After failing for a few more miles & stopping by running into curbs, it started failing off & wouldn't go.  The lion kingdom long believed the problem was salt water getting into the switch, but didn't know of a foolproof solution or why it started failing off.  There was also the chance of salt water shorting pins.

    The outside was covered in salt & hot glue from a re gluing 2 years ago.  It actually resumed service in 2016.  Its previous life was a boundary sensor on the DVD robot from 2002-2009.

    The teardown revealed a clean spring with good tension, despite its mileage.  It makes sense since the switch is rarely toggled.  A 10 mile run with no traffic can be done in only a single button press.  The steering buttons take the most beatings.

    The problem was the wear on the conductor.  This clearly would have trouble conducting when it was dry.  It was more like arcing wear it could have experienced in a former life.  To fail on, a water drop must have formed in the tiny gap.  The pullup resistor was only 50k.  Unfortunately, there was no evidence of salt water anywhere inside the switch.  This leads to the failures coming from shorted pins.

    Another unlikely option is the spring getting weaker over time, until it would engage the conductor but  not disengage it, in hot enough weather.  The only force available to move the conductor is the spring tension & not the operator.  There were still definite click sounds of the spring disengaging.

    The switch was acquired around 2001 & it was already over 20 years old by then.  It was now over 40 years old.  Lions only used it in low current applications, as a boundary sensor.

    Technology connections funnily enough made a video about switches on the day of the failure.

    The mane idea is the force on the conductor comes entirely from a spring.  No amount of pressing on the switch makes the conductor move more forcefully.  They use a spring to make the switch bounce & arc as little as possible.

    A layer of E6000 was added to the new switch, to try to seal it from water.  The circuit board got another layer of polyurethane.

  • More gopro 7

    lion mclionhead07/04/2019 at 21:45 0 comments

    Based on a more complete picture of the features from Rainmaker Guy & the limited teardown information, the gopro7 is the same as the 6 except for the DDR being doubled. Doubling the DDR was the key to improving the stabilization.

     The stabilization sauce is implemented in Japan by socionext.com. The 2 key innovations in the last 5 years are read ahead stabilization & rolling shutter correction. Lions lived in a time when the 1st single chip encoder for H.264 came out, just 13 years ago. It was a stretch just to encode 720p on a single chip. It took 2 chips to encode 1080p. 


     Today, the Socionext SC2000 encodes 4k 60fps in H.265 while also doing read ahead stabilization, rolling shutter correction, & camera stitching. It was only a year ago that lions still had a computer with 2GB of DDR taking up a stick on a motherboard.


     All the image stabilization is driven by an IMU with a samplerate of 6400Hz. The fastest lions used in quad copters years ago was 1khz. At 6400Hz, they get 106 readings in each frame. It can easily detect changes in motion at different points in the scanning of the sensor. The memories of jello are gone. If only DSLR's implemented rolling shutter correction with gyros.


     The key to stabilization was pioneered at Google for stabilizing gootube videos. They realized buffering several seconds of video into the future allowed the algorithm to anticipate future motion out of the sensor area. The algorithm could begin panning the video projection sooner rather than after motion was already out of bounds, giving much smoother results. The same thing is done for limiting audio loudness, but here it's done with video. The effect of read ahead stabilization is quite dramatic, with no significant increase in sensor size.




    Cautionary tale for stock pickers.  Lions never bought any stock & weren't liked by their hiring manager, but despite all that going against them, the results from these cameras were always a cut above.  

  • More gopro 7

    lion mclionhead07/04/2019 at 21:40 0 comments

    Based on a more complete picture of the features from Rainmaker Guy & the limited teardown information, the gopro7 is the same as the 6 except for the DDR being doubled. Doubling the DDR was the key to improving the stabilization.

     The stabilization sauce is implemented in Japan by socionext.com. The 2 key innovations in the last 5 years are read ahead stabilization & rolling shutter correction. Lions lived in a time when the 1st single chip encoder for H.264 came out, just 13 years ago. It was a stretch just to encode 720p on a single chip. It took 2 chips to encode 1080p. 


     Today, the Socionext SC2000 encodes 4k 60fps in H.265 while also doing read ahead stabilization, rolling shutter correction, & camera stitching. It was only a year ago that lions still had a computer with 2GB of DDR taking up a stick on a motherboard.


     All the image stabilization is driven by an IMU with a samplerate of 6400Hz. The fastest lions used in quad copters years ago was 1khz. At 6400Hz, they get 106 readings in each frame. It can easily detect changes in motion at different points in the scanning of the sensor. The memories of jello are gone. If only DSLR's implemented rolling shutter correction with gyros.


     The key to stabilization was pioneered at Google for stabilizing gootube videos. They realized buffering several seconds of video into the future allowed the algorithm to anticipate future motion out of the sensor area. The algorithm could begin panning the video projection sooner rather than after motion was already out of bounds, giving much smoother results. The same thing is done for limiting audio loudness, but here it's done with video. The effect of read ahead stabilization is quite dramatic, with no significant increase in sensor size.




    Cautionary tale for stock pickers.  Lions never bought any stock & weren't liked by their hiring manager, but the results from these cameras were always a cut above.  

  • Gopro 7 stabilization

    lion mclionhead06/27/2019 at 22:41 0 comments

    Gopros had advertised stabilization for years, but only the marginal amount found on camcorders 20 years ago.  The mighty Yi 4k was a change in form factor with little improvement.  The gopro 7 was the 1st to advertise enough stabilization to approach gimbals.  The DJI action cam just looked like junk, cropped more than the gopro & had lousier color.

    Suddenly, the goo tubes lept ahead of the lion kingdom in terms of stabilization & the quest for improved stabilization got more intense.  The lion videos were truly shaky relics in a world of rock solid videos.

    The lion kingdom got by with software stabilization for 20 years & never really matched today's standards.  The lion kingdom was so desperate to capture decent footage of its mane, the decision was made.

    In reality, the gopro stabilization doesn't work in 4k wide mode.  It works in 4k linear & all modes below.  The most aggressive gimal-like stabilization only works in the "linear" modes.  The fisheye/wide modes offer minimal camcorder stabilization from 20 years ago.  There's no difference between 4:3 & 16:9 modes, so pick 4:3.  

    It doesn't change the cropping to enable stabilization & there's no way to manually crop the modes to vary the stabilization.  In unstabilized modes, the sensor area is thrown away.  It's disappointing that the amount of cropping can't be adjusted to adjust the amount of stabilization.

    The integrated video screen is a bulky, fragile, heavy, slow, battery draining pain.  There is no longer a way to use it without the screen.  Many methods have been tried to keep it from shattering.  The enclosure provides some protection, but lions often use it out of the enclosure.

    Like the other gopros, it uses the battery to record 4K, despite USB being plugged in.



    There's no way to turn off the screen manually, only set the timeout as short as possible & reduce the brightness.  The GUI is so slow, it's like 2007 again before Steve Jobless showed everyone how to do it.

    The front lens cover is replaceable & the lion kingdom wishes it knew all the lenses were replaceable, 4 years ago.

    25" has been the maximum height for a camera pole with significant reduction in maneuverability & very shaky results.  Compare the stabilized gopro 7 with the unstabilized 4.

    Stabilized:

    Unstabilized:

    The 1st run video was amazing.  The stabilization on the robot wasn't steadicam grade & slightly behind gimbal grade, but far ahead of the footage on the other goo tubes.  Would call it slightly behind the steadycam & maybe equivalent to the 1980's Star Wars footage.  It was worth $330 for that level of improvement.  The cropping cut off the lion's head for most of it.  You either have to stand farther back or aim it carefully.


    They dramatically increased the saturation.  Audio is heavily processed to remove wind noise.  It's so processed & stabilized, it's like more of the information is coming from the software than the sensor.

  • Tire wrapping

    lion mclionhead05/31/2019 at 04:39 0 comments

    The new front tires were last year's old rear tires.  After a few rotations, they were done after no more than 200 miles.  The nylon wrapping was the same as before, gluing 1/3 at a time & holding it until it stiffened slightly, then gluing around a 2nd time.  This time, a bead was laid on the 2nd day to try to make the irregularities slap around less.  

    The handle strap proved to have another use besides making the handle removable.  It allowed easily strapping stuff on top of the container.  It was top heavy but a game changer.

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