The High Pro Glow

Welcome! The topics introduced in this blog will vary wildly. Here, you will find a lot of topics that might help some of those in need. I post off-beat information, hard to find history, & stuff that is otherwise seldom regurgitaited in our modern place. Sit back & find something interesting. Comment if you have a need or suggestion.

Thank you for crossing paths!

Christopher R. Smith (aka. Littlehorn)

I've got it on! Have you got it on?

Tuesday, April 25, 2017

F.I.R.S.T. World Championship 2017 Houston, Texas

The largest robotics competition had to be split into 2 venues in different states. Yes, this event is that big. The actual space needed is enormous. No single complex can accommodate the excitement.

This is the first year of 6 that Houston and the George R. Brown Convention Center will host the F.I.R.S.T. World Championship. Where 6 billion robotics students, coaches, mentors, parents, event coordinators, exhibitors, and service personnel from everywhere will mix for a week.

Since 1998 my experiences of this high energy event have been of places where brains are on full speed..high-intenstity robot action is at every turn..there is no time to rest..go..go..go! This time was the same. I have exactly 4 pictures! One from my 18th floor room at the Marriott Marquis, a blurry one of me, the MCP, and one shot over the GRB towards the obscured San Jacinto Monument. Guess which is which.

I was there as a MINDSTORMS Community Partner (MCP) showing robots with LEGO Education. Meeting all of the attendees is the best part. People from everywhere..all with similar interests and interesting stories.

Being the first year in Houston..the event coordinators and facility workers herded the cats pretty well. The coming years are sure to run even smoother.

Here are some links to people that used their cameras...

Tuesday, February 28, 2017

Balancing 3-Blade Propellers

The information presented here will grow. It's current form is made available to get folks moving towards saving another Bebop from vibrational induced death. More details will be added as time allows. Corrections and suggestions are always welcomed. Now.. On to the topic...

Balancing propellers greatly reduces vibrations that cause component damage and jello in video recordings. A perfect bench task for rainy days. Balancing is not difficult but does require a little patience and a bit of time..however, the results are well worth the effort.

Parrot Bebop 3-blade props are a patented proprietary design with hubs (holes & w/o holes) that help users install the correct props onto the correct motors. The props without center-holes present a problem for balancing. Balancing 3-Blade Propellers without center holes is possible using one of these optional methods and their tricks.

Starting with new parts is preferred. Balancing damaged parts may not have the desired result. If a rotor cage is warpped, or a motor shaft is bent, or a prop is damaged/bent..you are wasting your time balancing them into the mix. New parts are not balanced. Damaged parts shouldn't be used. Inspect every part very thoroughly before balancing them. 

The Optional Balancing Methods...

1. Non-Powered Dynamic Balancing
Using a Bebop motor bearing shaft to support an uninstalled rotor with a prop attached. Hand-spin and gravity isolating. May be the most inexpensive method to employ..if a sacrificial motor can donate it's bearing shaft. 
Startup cost may be free or $10-$30 USD.
Supplies: one sacrificial motor. See video below.
Pros: Simple process. Low startup skill-level required. Quick to setup and use.
Cons: Analog, one motor sacrificed. Motor not powered through operational range.

2. Dynamic Laser Balancing
Uses laser reflection to visualize vibrations of one assembled motor/rotor/prop mounted on its arm and independently powered through its operational range. Vibrations are isolated while one motor is running as speed is increased. Requires motor circuit isolation and independent power via a 3S LiPo battery, electronic speed control, and a servo motor controller.
Startup cost is about $40 USD.
Supplies: laser, small mirror or piece of a CD-ROM disk, 3S LiPo, ESC, Servo Motor Controller.
Pros: Balances through powered range.
Cons: Motor circuit isolation. Moderate setup, startup skills, and equipment costs. 
Video: coming soon

3. Dynamic Vibration Reduction
Uses a vibration detection and imaging smart phone app to visualize vibrations of an assembled motor/rotor/prop mounted on its arm and independently powered through its operational range. Requires disconnecting one motor for independent power. Vibrations are isolated while one motor is running as speed is increased.
Startup cost is approximately $40 USD before smart phone costs.
Supplies: Smart Phone, 3S LiPo, a 5-6v battery, brushless ESC, Servo Motor Controller.
Pros: Balances through powered range.
Cons: Motor circuit isolation. Moderate setup, startup skills, and equipment costs.
Video: coming soon


Pic of Typical Balancer: 
A typical balancing jig uses a central support rod through a prop's center-hole. Good for props with center-holes..impossible for props w/o center-holes. I wouldn't recommend drilling a hole. Fracturing the plastic hub is easy and risks failure mid-flight.

Thursday, February 23, 2017

'Space Shuttle Door Gunner' My Version...


A 'Space Shuttle Door Gunner' (or, SSDG) is used to describe someone that is bragging about some ultra-cool job position or experience not specifically related to military service. Similar to 'stealing-valor' but the teller usually isn't claiming to be or have been enlisted in the military. Merely some kind of amazing inflated story about their abnormal civilian work.

Stories of being a civilian helping Aliens fight Aliens on the Dark Side of the Moon..and other tall-tales of crazy-heroism, of super-secret operations involving the darkest covert groups doing unimaginable 'work', or living through death-defying acts in that line of work. Ref. the movie "Gravity". Maybe not the healthiest lies..but, still not the types of people that steal valor and need mental help but instead choose to try bragging for 'wows!' or to steal a veteran discount.

Sometimes a story might be legit. Especially, if there actually are space shuttle door gunners fighting aliens on the dark side of the Moon. Sure, why not..? Or, someone might have tales of lesser feats that still might be hard to believe.  The only legitimate reason to practice being a SSDG is story-inflation to score.

In the James Bond movie 'Moonraker'...there is a moment between Bond and Miss Moneypenny that exactly demonstrates the legitimacy of story-inflation to score and its entirely acceptable. As long as scoring IS the result, the ends justify the means. His reason below is even used by a lot of SSDGers. But, this wasn't for Miss Moneypenny and Bond never has to inflate his stories to score with chicks...watch the movie though. Miss Moneypenny had a burning crush for Bond.

Miss Moneypenny: James! But, why are you so late?
James Bond: I fell out of an airplane without a parachute. Who's in there?
Miss Moneypenny: Q and the Minister of Defense.
James Bond: You don't believe me do you?
Miss Moneypenny: No. And you should go right in.

So, I know there were no door gunners in NASA's Space Shuttle program..I Was There..in the bowels.

Maybe 2006, STS OV-095 Payload-Bay
My actual stories sometimes seem like B.S. Its hard to lie when the truth is crazy enough. But, there was a time when 'my office' (my desk, chair, phone, calendar, manuals, file cabinets, and space aircraft bits...but, no mini-guns) happened to actually be in the payload-bay of one of NASA's Space Shuttles...the OV-095. The reasons why the OV-095 payload-bay would become office space is simple. Office space in the Space Shuttle Avionics Integration Labratory Bldg. 16 and 16A was very limited. Since I was tasked with watching every bit of the OV-095 ..my office was smashed into the payload-bay until 'better' office space opened up about 2 years later. I do know that simulated space is still very cold. Here is a picture of me nearly freezing. The blue cabinets were full of computers and other assorted flight support equipment needing a lot of cooling. 

Sunday, February 12, 2017

Parrot Bebop 1 Battery Balance Port

The Parrot Bebop 1 LiPo battery can be charged with a much better balance charger than the stock charger.  To do so only requires a couple of connections for a B1 battery to hookup to an typical LiPo Balance Charger.  The battery has the required ports just not in the typical locations or using the typical connectors. The B1 battery's balance port is embedded into the battery enclosure above the main power output connector. Those 4-golden contacts require a special balance connector. Reaching them in some way is needed in order to use an aftermarket balance charger. A few options exist to make the connections. One is already in your junk pile...I'll explain...

The easiest, quickest, and cheapest route to the balance port is to use a part from the stock charger..hey, it saves $5-$10 and repurposes a hunk of junk. You might think it's a sacrifice..but the stock charger isn't healthy for any LiPo investment anyway. So, hack it open and remove a little bit of its guts. That is a picture of the 3S 4-wire balance cable removed from the stock charger. This is the part needed to connect between the new charger and the battery's 4-golden contacts for balance charging and to LiPo checkers to measure the individual voltages of the 3 internal cells. The pics below will help you hack the part out. 

Start with 2 screws under the bottom corners of the stock charger's back label.  Some rubber glue is holding components in place..just carefully remove the glue until you free the parts. Separate the halves and disconnect the 4-wire connector without damaging the wires. The rest of the disassembly is just a matter of removing more rubber glue and parts until the little adapter is free from the stock charger.
Once free from the stock charger..the little adapter requires a secure connection to the 4-golden contacts of the battery before charging. Several ways to position the connectors could be developed to accomplish a firm connection. Hot Glue is a great filler. Part of the stock charger's shell could be used as a tray or to fabricate  a special connector for quick and secure connections. The little balance adapter can be stacked on top of the mini-Tamiya connector for the main power connection..as in a picture below. The mini-Tamiya has a lock-clip that can be snipped off to make some room and disconnections easier. Sometimes the springs and 4-golden contacts may need cleaning to make a perfect connection.

The final configuration can look like this: (this example is by Jimmy Thompson)

Option #2 to reach the 4-golden contacts of the balance port requires some time, money., and a bit of luck..since the ready-made part is becoming rare. This Anbee/YX Bebop Charge Adapter Tray/Plate is/was available at Amazon, eBay, and other online shops for about $5. It is usually sold-out in every place other than China..so be prepared to dig for it and wait for it to arrive. It is a structurally stable setup and is worth the price and wait. So, the stock charger's balance adapter might be the best route..but, this jig works very well and can also be used with a LiPo checker to quickly measure voltages. 

It is very important to connect both the main Black/Red power port leads and the Balance lead to the charger to properly 'Balance Charge' multi-cell LiPo packs such as the Bebop 1 3S (3-cell) battery. The charger must be set to 'Balance' charge..not just 'Charge' or 'Fast Charge' unless the charger is actually balancing with those settings.

All LiPo multi-cell battery packs like the Bebop 1 require 'balance' charging to insure the internal cells (3 inside B1 packs) have the same amount of charge to supply the required voltages as needed during a flight. Some of Parrot's stock chargers have a few problems. Mainly, it does not show you the pack voltages or any other information about the battery or its health. Some stock chargers do not fully-charge a pack or balance the cells properly. I recommend finding a better battery charger and picking up a few habits that will make Bebop batteries last a looong time and live very productive lives. Several great balance chargers can provide far more therapy for expensive LiPo batteries. Give one a try and realize why saving expensive LiPo batteries will help the fun keep flying high.

If have a question add it in the comments!

Have Fun!

Wednesday, January 18, 2017

Parrot Bebop 2 Battery Charging

The Parrot Bebop 2 battery pack provides the only means of power to maintain flight. How well and how long depends on a few easy to learn maintenance habits that will help Lithium-Polymer ('LiPo' or 'Li-Ion Polymer') packs perform as expected and live longer lifespans. Weakened LiPo packs can cause legitimate 'fly-aways' usually from bad cell voltage fluctuations leading to the unexpected system reactions to unusual battery behaviors..this also can trigger shutdown mid-flight. The Parrot battery packs are good quality but expensive and need attention like most other flight LiPo or they will die and take your Bebop too.

Ready for the meat of the subject now? It will be easy to understand and worth the effort. After you read this you will have a much better understanding of LiPo therapy. I will start with the Stock OEM Parrot Bebop 2 battery.

The Parrot Bebop 2 OEM battery pack is an encased 3-cell 2700mAh 3S 11.1volt LiPo. Parrot recommends "Charge at 3.5A Max" which is higher than the usual "1C charge rate" of typical R/C LiPo batteries. "1C" means that a battery can handle being charged at 1x the specified mAh written on a LiPo battery. Higher performance packs can handle higher than 1C charge rates..but more on that and connection details later.

LiPo Do-Nots...(one "Do"now..always watch LiPo charge)

-Do Not discharge below 10% remaining power as reported in FreeFlight Pro. Land well before this number or risk discharging below a safe voltage level for LiPo to remain healthy. Every dip below 3.2 volts per cell will add damage and shorten its life and harm expected performance. Failing cells will have voltage levels lower and weaker than the other cells. All of the cells should be about .2 volts within each other. A dying cell will not hold a charge as well as the others..or have the capacity. It could be target-charged to bring it up to match the other voltages and become balanced with the other cells...but it may be dying anyway. Discharging to zero equals LiPo death.
-Do Not store battery packs while discharged too low or with fully-charged voltage levels. Below 3.2 volts per cell is too low. Fully-Charged and it is like a grenade ready to blow. Flying a pack discharging it to about 45% to 60% as reported by FreeFlight Pro will pull the voltage level down to an approximate Storage Voltage Level or 3.75 - 3.85 volts per cell.
-Do Not let battery packs get too hot. At 140F damage occurs and where LiPo is at risk of rupture or 'venting'..like a volcano. If in your hot car or sitting on a charger too long in your home..the result can be disastrous. Normally, the battery only should be a little warm after a flight. LiPo likes to be about 95F at lift off summer and winter. Though, let the battery cool down between charge cycles and flight.

Note: FreeFlight Pro reports remaining battery charge measurements taken during flight. Voltages fluctuations can cause reporting errors. A failing battery may even dump or fail to supply voltage demands to the point the system shuts down..and the Bebop falls. Cold weather has the same affect on all LiPo chemistry cells.

Now, the "Do's" will be explained in the handling and charging processes described below. New LiPo packs need a few cycles after birth/storage to perform as expected and become trusted for expected flight performance. So, don't trust them for a few flights..keep the Bebop low and slow until you get a good feel for a battery's behavior and performance before you get too far down the road.

Charging the Bebop batteries with the included stock charger is not a great solution to continue for long. The batteries can discharge below the level that triggers the stock charger to charge. Some tricking is needed..but not recommended. Some Bebop 2 boxes have been on the shelf for a year or more at this point in time. Batteries from new sealed boxes can self-discharged to unhealthy level and may not be capable of supporting safe flight. The stock charger do not provide any information about the pack or its status. Without a way to monitor your batteries it is impossible to know enough to keep the Bebop flying as expected for as long as expected. The stock charger can balance the packs well enough for 6 months of fun. But, these packs can usually live a much longer and more productive lives.

To Charge a Parrot Bebop 2 Battery pack..first, stop using the stock charger. Then, find a better balance charger with a display that can do more and show you what is happening with the LiPo cells. I use the one pictured here. It is very capable and more modern and being actively supported..more than 4-button chargers these days. 4-button chargers are really good and some offer some really great functions. Most of the veteran users will use them. New chargers are being released often. The iSDT chargers are very easy to use, updatable, and have performed better than my 4-button chargers.

Here is my iSDT SC-620 charger connected to a Bebop 2 battery. The custom adapter cable shown in the pic is needed to complete the setup. That adapter is hand-made and different versions can be purchased from different sources. This one is from Clifford Raccani. Contact him for a one until he quits making and selling them..or contact me..I will be making several different versions for different applications for North American users. If you have basic solder skills or want to learn how to make your own cable..watch Clifford's video: https://youtu.be/orESacSy2ro



The short main power portion has an XT-60 connector (yellow) soldered on the end leading to the charger's main output. The XT-60 is a very common connector used with many LiPo batteries, chargers, and other RC systems. Usually, this would connect to an adapter supplied with the charger to complete the connections.

NOTE:  Both the 4-wire balance lead and the 2-wire main power lead need to be connected to the charger to be able to balance charge the internal cells properly.

Due to the flexibility of the iSDT chargers, it is possible to charge a LiPo battery with a larger LiPo battery, or from a larger deep-cycle 12volt battery, or from an old PC's power supply, or with an old 12volt 5Amp laptop power supply from a wall plug. Since this is a fact..a power supply is also needed to power the iSDT chargers. There is an  included 12volt adapter with alligator clips and the XT-60 that matches the iSDT charger's power input port. Other options will need the XT-60 to match the charger. If soldering is not your preferred method of DIY..you need to find the appropriate adapters to complete the connections.


An optional charge setup requiring less work upfront are 4-button chargers. Below is a Tenergy TB6B 4-button charger connected to the Bebop 2 battery. Many 4-button chargers include a 'squid' connector lead with an assortment of common connectors to match most systems in use today. Some 4-button chargers will need a power supply. The Genuine SkyRC Imax B6ACv2 has an internal power supply making it a little easier on beginners. Most 4-button chargers use 4mm banana plugs to output the main charge current to the battery lead..I have one with the yellow XT-60 connectors as seen in the picture. Other good brands of 4-button chargers are available. Just be sure to buy "Genuine". Adjustments can be made to most of these units to better calibrate its measurements. But, usually most of them are close though the readings may not be in sync with every other voltage meter that isn't calibrated either.

Setting a charger to charge a Bebop 2 battery.

Generally..make sure that you are charging to the battery's specs as labelled on the battery and that the charger is always set to "Balance Charge"..Not "Fast Charge" or even just "Charge". Both the 4-wire balance connector and the 2-wire main lead connector have to be connected for the charger to balance charge the internal cells properly. When balance charging, the input charge is individually added to each cell and they are increased equally until fully-charged or when the set cut-off voltage is reached. Most chargers will automatically set some aspects like battery type, cell number, max charge voltage level cut-off, discharge voltage level cut-off, a set storage level voltage, and possibly a charge rate amperage value. Nothing to sweat about.

Balance charge Bebop 2 batteries at a 3.5Amp charge rate or below. This setting is important..and selectable before starting a charge process. Some tests suggest that lower/slower charge rates help achieve a longer LiPo lifespan. I wouldn't recommend trickle-charging the batteries throughout the charge cycle because it would take a long time to charge and balance high-capacity 3S packs and there is no real benefit by charging slower than half the C rating. A 2700mAh pack (such as the B2 stock battery) has a C rating that suggests it can be charged at 2.7Amps. However, as mentioned before, Parrot recommends "Charging at 3.5A Max" which is higher than a usual 1C charge rate of LiPo batteries. I have charged one of mine at 3.5A for over a year with no signs of damage.

Whatever charger you do employ..watch the charger or be near it while it is powered on and especially while charging anything.

Keep it Safe. Keep it Healthy. Enjoy the Skies!

Thursday, December 29, 2016

RANDOM.ORG

When Random needs to be "Truly Random"


Tuesday, December 27, 2016

Winter Flights Need Warm LiPo Batteries

The winter chill will arrive if it hasn't already. Time to look at your power sources and how you can help squeeze more flight time in frigid temperatures. LiPo battery packs lose about 20-40% of their capacity and performance potential in cold weather. Voltage levels fluctuate when the internal battery temperatures slow the release of the battery's stored charge. They can start fully-charged but appear to empty very quickly because the demand is greater than the supply is releasing. This can cause flight systems to have inaccurate reactions to power measurements. Systems will report low battery power remaining or trigger shutdown early. Warming batteries before flights can significantly improve cold weather performance.

The Bebop packs are enclosed inside a thin-walled black plastic shell that does provide a little protection from the elements. However, if a battery is charged and rested in a home before a flight outfoors its internal temp could be rather low for to perform as expected. LiPo packs have a starting-temperature sweetspot of about 95F to maintain winter flight as expected. That is a good start to have enough heat built-up to sustain normal performance throughout a cold flight.

I use this $15 'Turnigy LiPo Battery Warmer Bag' I bought from Hobbyking.com last year. It is Adjustable and monitors its own temperatures! There's room to warm two Bebop 2 battery packs. Making a DIY warmer isnt rocket science. But, this battery warmer is the best commercial-off-the-shelf thing I have used yet. Such hi-tech warming methods in the past..like, pockets, a baby bottle warmer, and chem-pack hand-warmers. Last winter, a user covered the Bebop battery with a patch of fur. It was stylish and may have even kept it warmer to some degree.

Regulating specific temperatures should not be left to the warmer controls. It is thermo-regulated..but I would acquire a second opinion and limit potential over-heating problems.


So, warming is good...but too warm is not good. Damages occur inside LiPo cells when internal temperatures approach 140F. Bebop packs do not seem to run hot normally (even in Texas summer heat). But, heat and heating can become a problem if a pack is warmed too hot and then ran hotter during a flight..+140F can happen. Measuring pack temps after flights and monitoring the temps in the warmer bag can give you a better idea how much heating can be applied safely. 

Here is the warmer powered by a LiPo pack and an adjustable low-voltage alarm to monitor the battery's charge level. This alarm will let you know when the battery reaches its lowest safe capacity before over-discharge and damage. But this alarm will not prevent over-discharge all by itself. The user needs to remove the LiPo when the alarm reports the low-voltage condition. Allowing it to continue to discharge below 9.6 volts will cause cell damage within the LiPo pack. It is a good idea to stay nearby when using this configuration.
Here is an $15 12v Sealed Lead-Acid Battery powering the warmer. That is the cable included with the warmer. This is a similar battery to what is in automobiles..and commonly used in RC base stations and support equipment. These batteries can supply power for along time. However, it is a good idea to also use a 12v low-voltage alarm..or even with an automatic cut-off function. Like the 12v Battery Low-Voltage Alarm & Over-Discharge Protection Board. Just program it to cut-off at 10.4volts. $11 of Yes, Please! It is connected between the battery and the warmer or any other 12v load.

Maintaining battery conditions can help flight enjoyment and reduce risk of losses..why not warm'em if you got'em before you fly'em...or, Winter may take a chilly bite..leaving a chunk missing in your drone-soaked soul...

Have Fun!

Monday, December 26, 2016

Parrot Bebop 1 Battery Charging

The Parrot Bebop 1 battery pack provides the only means of power to maintain flight. How well and how long depends on a few easy to learn maintenance habits that will help Lithium-Polymer ('LiPo' or 'Li-Ion Polymer') packs perform as expected and live longer lifespans. Weakened LiPo packs can cause legitimate 'fly-aways' usually from bad cell voltage fluctuations leading to the unexpected system reactions to unusual battery behaviors..this also can trigger shutdown mid-flight. The Parrot battery packs are good quality but expensive and need attention like most other flight LiPo or they will die and take your Bebop too.

Ready for the meat of the subject now? It will be easy to understand and worth the effort. After you read this you will have a much better understanding of LiPo therapy. I will start with the Stock OEM Parrot Bebop 1 battery.

The Parrot Bebop 1 OEM battery pack is an encased 3-cell 1200mAh 3S 11.1volt LiPo. Parrot recommends "Charge at 1A Max" which is lower than the usual "1C charge rate" of typical R/C LiPo batteries. "1C" means that a battery can handle being charged at 1x the specified mAh written on a LiPo battery..but more on that and connection details later.

LiPo Do-Nots...(one "Do"now..always watch LiPo charge)

-Do Not discharge below 10% remaining power as reported in FreeFlight Pro. Land well before this number or risk discharging below a safe voltage level for LiPo to remain healthy. Every dip below 3.2 volts per cell will add damage and shorten its life and harm expected performance. Failing cells will have voltage levels lower and weaker than the other cells. All of the cells should be about .2 volts within each other. A dying cell will not hold a charge as well as the others..or have the capacity. It could be target-charged to bring it up to match the other voltages and become balanced with the other cells...but it may be dying anyway. Discharging to zero equals LiPo death.
-Do Not store battery packs while discharged too low or with fully-charged voltage levels. Below 3.2 volts per cell is too low. Fully-Charged and it is like a grenade ready to blow. Flying a pack discharging it to about 45% as reported by FreeFlight Pro will pull the voltage level down to an approximate Storage Voltage Level or 3.75 - 3.85 volts per cell.
-Do Not let battery packs get too hot. At 140F damage occurs and where LiPo is at risk of rupture or 'venting'..like a volcano. If in your hot car or sitting on a charger too long in your home..the result can be disastrous. Normally, the battery only should be a little warm after a flight. LiPo likes to be about 95F at lift off summer and winter. Though, let the battery cool down between charge cycles and flight.

Now, the "Do's" will be explained in the handling and charging processes described below. New LiPo packs need a few cycles after birth/storage to perform as expected and become trusted for expected flight performance. So, don't trust them for a few flights..keep the Bebop low and slow until you get a good feel for a battery's behavior and performance before you get too far down the road.

Charging the Bebop batteries with the included stock charger is not a great solution to continue for long. The batteries can discharge below the level that triggers the stock charger to charge. Some tricking is needed..but not recommended. Some Bebop 1 boxes have been on the shelf for a year or more at this point in time. Batteries from new sealed boxes can self-discharged to unhealthy level and may not be capable of supporting safe flight..or the batteries may be OK just too low to trigger the stock charger to start charging. The stock charger does not provide any information about the pack or its status. Without a way to monitor your batteries it is impossible to know enough to keep the Bebop flying as expected for as long as expected. The stock charger can balance the packs well enough for 6 months of fun. But, these packs can usually live much longer more productive lives.

To Charge a Parrot Bebop 1 Battery pack..first, stop using the stock charger. Then, use a better balance charger with a display that can do more and show you what is happening with the LiPo cells. I use the one pictured here. It is very capable and more modern and being actively supported..more than 4-button chargers these days. 4-button chargers are really good and some offer some really great functions. Most of the veteran users will use them. New chargers are being released often. The iSDT chargers are very easy to use, updatable, and have performed better than my 4-button chargers.

Here is my iSDT SC-620 charger connected to a Bebop 1 battery. The inexpensive adapter cable and balance adapter charge tray shown in the pic are needed to complete the setup.

The short main power adapter cable is a special little part but only $3 at HobbyKing.com and ready to use as-is. The Bebop 1 battery uses a mini-Tamiya connector molded into the shell that has its polarity reversed than usual mini-Tamiya connectors. This little adapter has a mini-Tamiya (lightgreen) and an XT-60 connector (yellow). The XT-60 is a very common connector use with LiPo batteries and chargers.

The Bebop 1 battery is a little different than a typical hobby LiPo battery pack with its own balance connection embedded into the battery shell. instead of being on a wired cable. These 4-golden contacts are needed so each of the 3 internal cells can be accessed and their voltages balanced during charging. These contacts can be reached by 2 ways. One requires a purchase..and one method can utilize a part from the original stock charger for free. Here is information on how to use the stock charger to save some money and time..http://thehighproglow.blogspot.com/2017/02/parrot-bebop-1-battery-balance-port.html

The second option the reach the balance port is the "Anbee/YX Charge Adapter Tray" is $5 and available through Amazon, eBay, or many online R/C shops. It is needed to reach the 4-golden balance contacts above the main power connector of the battery in order for the charger monitor individual cell voltages and balance the cells to approximately the same voltage levels.

Due to the flexibility of the iSDT chargers, it is possible to charge a LiPo battery with a larger LiPo battery, or from a larger deep-cycle 12volt battery, or from an old PC's power supply, or with an old 12volt 5Amp laptop power supply from a wall plug. Since this is a fact..a power supply is also needed to power the iSDT chargers. There is an  included 12volt adapter with alligator clips and the XT-60 that matches the iSDT charger's power input port. Other options will need the XT-60 to match the charger. If soldering is not your preferred method of DIY..you need to find the appropriate adapters to complete the connections.

Here is a Tenergy TB6B 4-button charger connected to the Bebop 1 battery. Many of these chargers include a 'squid' connector lead with an assortment of common connectors to match most systems in use today. Some 4-button chargers will need a power supply. The Genuine SkyRC Imax B6ACv2 has an internal power supply making it a little easier on beginners. Most 4-button chargers use 4mm banana plugs to output the main charge current to the battery lead as seen in the picture below.

Setting a charger to charge a Bebop 1 battery.

Generally..make sure that you are charging to the battery's specs as labelled on the battery and that the charger is always set to "Balance Charge"..Not "Fast Charge" or even just "Charge". When balance charging, the input charge is individually added to each cell and they are increased equally until fully-charged or when the set cut-off voltage is reached. Most chargers will automatically set some aspects like battery type, cell number, max charge voltage level cut-off, discharge voltage level cut-off, a set storage level voltage, and possibly a charge rate amperage value. Nothing to sweat about.

Balance charge Bebop 1 batteries at 1Amp or 1.2Amp charge rate or charge current setting. Some tests suggest that lower/slower charge rates help achieve a longer LiPo lifespan. I wouldn't recommend trickle-charging the batteries throughout the charge cycle because it would take a long time to charge and balance high-capacity 3S packs and there is no real benefit by charging slower than half the C rating. A 1200mAh pack (such as the B1 battery) has a C rating that suggests it can be charged at 1.2Amps. However, as mentioned before, Parrot recommends "Charging at 1A Max" which is lower than a usual 1C charge rate of LiPo batteries. I have charged one of mine at 1.2A for over a year with no signs of damage.

Whatever charger you do employ..watch the charger or be near it while it is powered on and especially while charging anything.

Keep it Safe. Keep it Healthy. Enjoy the Skies!

How To Measure Parrot Bebop 1 & 2 Battery Voltages with a Multimeter!

Parrot Bebop stock OEM batteries are good quality but need attention. Knowing the individual cell voltages is a great thing even before you suspect a pack is unhealthy. You only have the stock charger and don't know how to see the individual cell voltages. Just use a Multimeter to find out. Each individual cell of a 3S (3-cell) 11.1 volt LiPo pack can be measured easily and all should be within .2volts of each other especially when balanced and healthy. Each cell should be under 4.20 volts when fully-charged, at 3.75-3.85 volts for storage, and never allowed to discharge below 3.2 volts per cell least damage or LiPo death is your preference. Never store a battery below 3.2 volts per cell and never store a LiPo fully-charged for more than a day or two. Discharging to zero equals LiPo death. A failing cell will not hold a charge as well as the other cells..or have the capacity or performance. It could be target-charged to bring it up to match the other voltages and become balanced with the other cells...but it may be dying anyway.

To measure individual voltages of a 3S LiPo battery use a common Multimeter (set to the 20volt range) and probe the battery contacts as shown in the pics below.

Handle the probes with care and aim well! Though, there isn't much risk of shorting due to the way the contacts are recessed in the connectors.

To complicate life to even higher levels..Parrot has created another charger and two more charge cables for the FPV line of equipment all using 5-pin connectors. The FPV Bebop2 Bundle includes a small Skycontroller 2 with a 2S (2-cell) LiPo battery. The SC2 battery should be removed from the SC2 for voltage checks. The new Bebop 2 5-pin charge cable can be used as in the pictures below. Just disregard the far left empty recess..it is not needed for Bebop 2 voltage checks.

How To Measure Parrot Bebop 2 Battery Voltages with a Multimeter





How To Measure Parrot Bebop 1 Battery Voltages with a Multimeter
Or, find one of these inexpensive little voltage checkers in shops everywhere. Any of these little buggers provide a quick check with instant evidence and nothing has to be remembered.

Now, these voltage measurement devices (or some) and this method do not measure the battery's ability to supply enough power to meet the demands of flight. The measurement methods detailed here are quick primary voltage level check without the battery under a load and is useful for spotting cells that are unbalanced and may be failing. A weak battery pack can appear strong when measured at rest..but one internal cell can be failing to have the performance capacity as expected. Weak cells cannot hold as much power or be able to keep up with the other cells in the pack. This can cause power shutdown/failure/loss during flight. The pack could not produce the required output. Additionally, Cold weather saps LiPo abilities of even more performance. Check them..Your Bebop depends on them!



Tuesday, June 16, 2015

Beyond SnapCAD - Step 1



   SnapCAD is a cool way to create a custom model and share it...and the images it can produce are pretty good for building instructions. But, there are ways to produce better images and building instructions from the SnapCAD model files.

   In this series I will describe the ways to process SnapCAD files to create better images and building instructions. While there are even more ways to do each, I will describe the methods I use. If you need more just ask. I've been in and around the LDraw community for over 15 years. I have obtained mass-quantities of knowledge in many of the programs that take CAD models far beyond the first step.

   I'll start with one simple instruction...and introduce the first new addition to the process..the awesome and very powerful program named "LDView". I used LDView to create the model images in this picture.

   LDView is a image rendering program that can use any LDraw standard parts library to produce stunning images from CAD rendered model files. LDView is very useful in many ways..use it to view a model being created or a finished model by spinning it around with a mouse, or take a high-quality snapshot of a model, or set it to be used by another program to produce images for building instruction layouts..but more about that use later in this series.

   LDView is designed with only the LDraw Parts Library in mind. and looks in the "LDraw" folder for all of the parts it needs to display a model. SnapCAD models can be opened and displayed with LDView..but not right away.  To view SnapCAD models in LDView you need to tell LDView where to find the VEX IQ SnapCAD Parts Library. Furthermore, sometimes the LDraw Parts Library and the VEX IQ SnapCAD Parts Library are installed on the same PC. Each of these scenarios can be satisfied so that both can coexist and used by LDView by simply directing LDView where to find the needed library or libraries. This involves merely inputting the path to the library or libraries. 

   If a typical LDraw renderer (MLCad, SR3D, or LDCad) and SnapCAD are installed on the same PC and you want to use LDView for either system...keep reading to setup LDView to display models from either when they are opened for viewing.

Configuring LDView:

Scenario 1:  SnapCAD Parts Library Only...

   If you only want to use SnapCAD with LDView...Open LDView, click File > "LDraw Dir..." ..browse/highlight the main SnapCAD folder and click "OK". This will allow VEX IQ SnapCAD models to be displayed. It will also use SnapCAD's specific color palette (LDConfig.ldr). *See Note below.

Scenario 2:  SnapCAD & LDraw Parts Libraries...

    To setup and use both libraries... Open LDView, click File > "Ldraw Dir..." ..browse/highlight the SnapCAD folder or the LDraw folder (choose the parts library you use the most). Then setup the 'Extra Directories' search process..click File > "Extra Dirs..." ..click the "C:\" button at the bottom of the dialog box..and browse/add the parts library folders "P" and "Parts" (add a line for each folder) in the main SnapCAD folder or the main LDraw folder. When a SnapCAD model or a LDraw/LEGO model is opened LDView will find/use the right parts library. *See Note below.

*Note: LDView uses the 'LDConfig.ldr' color palette file located in the chosen "LDraw Dir..." folder..which ever folder is set there. LDView will also use the 'LDConfig.ldr' file found in the folder set in the "LDraw Dir.." input for every folder setup in the "Extra Dirs..." search process.

That's it. Try LDView and make some snapshots! More about LDView's Settings later through the next parts of this Series.

Enjoy!

Friday, June 12, 2015

SnapCAD..Virtual Building for the VEX IQ System - Download Free!









SnapCAD for the VEX IQ System..Went Live Today! Download it for free from... SnapCAD

Please, see the instructions on the download page and more in the Help File inside SnapCAD. 
Much appreciation goes to the folks at VEX Robotics, to Philippe Philo Hurbain, the LDraw Community, and Michael Lachmann.
Let me know how you like it. It has been a long hard road to make this happen. Now, some of us can sleep for a few minutes.














--What is SnapCAD?


SnapCAD is free Computer-Aided Design software enabling users to design and create a virtual VEX IQ assembly or robot and produce printable, shareable building instructions. SnapCAD also enables design exploration when access to real parts is limited. The SnapCAD virtual parts library includes all of the VEX IQ building elements and never runs out. Use SnapCAD to document models that have been built with real parts, use it to test a novel idea in the virtual world before building it physically, or render and share creations with the world in the form of step-by-step building instructions! No usage license is required by educators.



The process of creating a new model consists of repeating a few actions in a sequence. Generally, start by finding a part and placing it into a drawing area, add a few more parts connecting them together, and add a step command. Step commands break up the model into steps to show how a model is constructed. For example...add a few parts, add a step command, add a few more parts, add another step command, a few more parts, a step command...and so on until a model is fully constructed. This is a simple example of the process. Read the rest of the helpful information about SnapCAD's powerful functions needed to complete detailed building instructions in the Help File via “Help > Help Topics” from the top menu bar.

--SnapCAD Background

SnapCAD is based on MLCad (and the LDraw-based standard). It is almost a direct rebranding..though, SnapCAD was custom built by Michael Lachmann (creator of MLCad) for VEX Robotics and the IQ system and has very unique changes & enhancements. We chose MLCad because it is small, simple, proven stable, powerful, created files can be used in other rendering tools, and most importantly..can be installed very quickly/easily on any Windows PC. It can be maintained and supported by VEX easily. Michael Lachmann (creator of MLCad) recreated SnapCAD for us. Master LDraw Parts Guru, Philippe 'Philo' Hurbain converted the VEX IQ parts for the SnapCAD virtual parts library and also worked through many other aspects that control the software. I am the SnapCAD Project Coordinator and a very experienced MLCad user with over 15 years CAD’ing and rendering for books. In March 2014 I asked Philo to convert the VEX IQ part files released online by VEX in same month. VEX later noticed what we had at the VEX IQ Super Users booth at the VEX Robotics World Championship 2014. VEX mentioned that they wanted to offer something simple that anyone with a computer could record their own robot designs and share them with other users. VEX is releasing SnapCAD free and no usage license is required by educators.

--What are the differences between SnapCAD and MLCad?

While SnapCAD is built from MLCad and are functionally the same they are still very different. Primarily, SnapCAD is optimized for use only with the new VEX IQ/SnapCAD parts library. New default SnapCAD settings, a new custom color palette, and part group categories were required to handle the new VEX IQ parts library to help users build quickly and easily. VEX wanted to release a package that contained everything users need to create VEX IQ models easily using almost any computer.

--How different is the SnapCAD Parts Library from other LDraw parts libraries?

The SnapCAD Parts Library was converted by Philippe "Philo" Hurbain from VEX's own official CAD STEP files modeled to create the real IQ elements. Not only are the SnapCAD parts different from other LDraw parts libraries (and the original 2014 VEX IQ parts library developed by Philo and offered on his website)..each part in the new VEX IQ Parts Library has a custom part origin (the 3D part centers which control part alignment). New users will benefit from using this new library together with SnapCAD to create IQ models very quickly while reducing the need to tweak part positions after they are added to a build window. Basically, the parts 'snap' into place within the grid. However, this 'snap' action is not like some other CAD program that use a “locked-snap” function when connecting to other elements. SnapCAD offers more flexibility in model rendering. This type of functionality does not prevent alignment mishaps but it does greatly reduce such problems. Part over-lap can occur. This offers the freedom to create odd part arrangements or special layouts sometimes needed for many different reasons. 

--Can the VEX IQ/SnapCAD Parts Library be used with other LDraw rendering tools?

Yes! However, the rendering tool must be corrected for VEX IQ part placement and grid movements. Colors will also need correction. Additionally, if users wish to produce high definition images or building instructions with other tools each must be set to locate and use the actual VEX IQ SnapCAD Parts Library. More information about using these programs will be presented in the future.

--Regarding "Snapping" virtual parts in SnapCAD

"Snapping" has been a deep desire of many users of these types of CAD programs for a long time. However, many software implementations have hindered the purpose by being too bloated or difficult to use. Some programs have strictly used snapping of parts and that has many undesirable drawbacks for some of the veteran users. An on/off snapping function would be the best method for some specific reasons. So, SnapCAD compromises to aid beginner users and satisfy veteran users by utilizing an adjustable grid which positions parts being moved into and around a virtual model. Movements of parts in an adjustable grid is like snapping but will also enable users to position parts in a more flexible way when needed and that need is evident when users build their own real-world model in any CAD program. To explain this a bit further…Problems arise when virtually rendering a real model with a CAD program using a locked true-snapping function. The main reason is that it is common for real VEX IQ constructions to have parts that were connected under some stress or flexed condition ("off-pitch"). Real VEX IQ parts (and every other brand) have a bit of flexibility which none of these CAD programs can replicate perfectly. So, if there is a flexed part in the real world model...the same cannot be rendered perfectly in the virtual CAD environment...especially, if the program uses only true-snapping functionality. This is why we chose a method utilizing an adjustable movement grid while still offering the greater ability for users to create (and complete) their virtual model even if an off-pitch alignment exists in their real-life model. True-Snapping will not allow misalignments to be achieved and that could prevent you from completing a virtual rendering. SnapCAD will allow you to complete building instructions with an accurate part list for a rendered model. Even if some 'fudging" is hiding visually.

This is not the only reason why SnapCAD is a great option across a large and diverse user demographic. More insight will be discussed later.

If anyone wants to ask me something off-line..my email is: the.littlehorn (at) gmail (dot) com

Monday, February 02, 2015

NASA Shuttle Avionics Integration Laboratory (S.A.I.L.) OV-095 - Historic Landmark

    Somehow, in the great scheme of things, The United States has chosen to take a break from Space Exploration..at least until a new leader might reignite public interest and support the fun to began again. However, it looks like the private sector could provide the next step into space. I wish things were like the old days. Back in the time when Americans ran on pride and actually made great things happen without much support from technology. When I became a Quality Assurance Inspector in the Shuttle Avionics Integration Laboratory (S.A.I.L.) for the (on-ground Space Shuttle) orbiter OV-095 in 1999, I understood the history that made NASA what it was to that point. The next decade was an evolution in a much different direction. The result was, more or less, the end. The S.A.I.L. was a very special place and an essential part of the entire program. It was the heart of America's space program. The S.A.I.L. facility, within the maze-like walls of Building 16A of the Johnson Space Center, is now a Historic Landmark. Visitors can experience the S.A.I.L. on Space Center Houston's Level-9 Tram Tour. If you want a little peek into the facility..watch these videos below. I'm in the first video more than a few times...and it is very nice to see the changes they made to the facility for visitors. In the second video, Don Magnusson shows viewers the glass box where visitors can safely view the payload bay of OV-095. That glass box sits where my "office" was located for a time.




Friday, June 20, 2014

Convert LDraw Parts to STL Files for 3D Printing

    3D Printers are becoming very affordable and really useful to prototype any idea. The ability to 3D print physical objects has also afforded solutions to many problems. One such problem is the fact that LEGO does not continually or currently produce every part/element they have produced in the past. Since many fantastic and useful parts are extremely rare or completely extinct the 3D Printing solution can help LEGO builders explore the possibilities of dormant or unobtainable elements. In this article I will quickly guide you through the simple process of converting LDraw Parts into STL files for 3D Printing purposes. It will require some knowledge in common Windows operations and in the software noted so spending a little time exploring the software will help you to grasp the process. I have converted the kit# 4481 Hailfire Droid Hoop Wheel part and created STL files and made them available HERE.

    To Begin..if you already have MLCad, the LDraw Parts Library, and LDView (must install 4.2 Beta 1) installed skip to Step 1 Below. If you do not already have MLCad, the LDraw Parts Library, and LDView installed, please use this CAD Quick Install Guide - LDraw to quickly install the software needed to easily use and convert LDraw Parts towards use with your 3D printer. Additionally, please send me some feedback on your experience using this guide!

Step 1:
Start MLCad and add a part file into a window at the center coordinates of x = 0.0, y = 0.0, z = 0.0. Save this file as an .LDR file to your PC.

Step: 2:
Start LDView and open the saved file.

Step: 3:
When the file is displayed within LDView's window..Navigate to File Menu > Export... export file by selecting the <Save as type:> dropdown box under the filename input box and select... "STL: Stereo Lithography File". Select the "Options" button and choose a dimensional unit..and save to your PC. There is a bug here..the "mm" and "cm" selections both produce files in "CM" units. It has been noted to the developer and will be fixed in the next LDView release.

Conversion Complete...now use this file in your 3D Printing software and print the part. These files can also be a starting point used to design new parts by altering the parts with other CAD software.

Not difficult. Feedback is appreciated!

The LEGO MINDSTORMS HoopRover History

The LEGO MINDSTORMS HoopRover model was first created back in early 2006 while I was part of the LEGO MINDSTORMS Developer Program Group (the MDP). It was also the first complete model I created with the NXT set. As part of our development process LEGO wanted the group to create some interesting models by combining the (then new) LEGO MINDSTORMS NXT Robotics Kit with existing production sets and elements. Several models were showcased on the MINDSTORMS main webpage and other places. I've always been interested in the robots and machinery of the Star Wars series and actually returned from my Dark Ages with the little LEGO Speeder Bike set #7128. When LEGO produced the Star Wars Hailfire Droid set #4481, I was thrilled. Specifically, the awesome gear wheels could be and were extremely useful in LEGO MINDSTORMS Robotics. I went for the challenge to use them during the MDP and was successful. The outcome was a graceful mix of minimal parts with awesome functionality. I wanted to create something with the wheels while I was stuck in rover making mode. I felt the hoop wheels provided a very “space rover” look together with the NXT elements. The main challenge of building with the hoop wheels is creating a precise LEGO drivetrain position for proper wheel/gear control. The hoop wheel‘s inside diameter gear and slot configuration made it difficult to render a perfect motor and grapple structure. But, the arrangement of the HoopRover is elegant and very efficient. The pBrick and chassis can roll over 360 degrees without falling away from the hoop wheels while also maintaining the proper gear mesh. It operates very smoothly and is very robust. While, the simple structure is strong, my objective was to save weight using the least amount of elements possible. 

The HoopRover can easily become a Hailfire Droid and although it does appear to be an NXT Star Wars Hailfire Droid, the plan was something entirely different with a different meaning. The truth is, my plan was to create a rover with the hoop wheels closer together at the top and a wider stance at the bottom. This angle was inspired by "MurderBall" the documentary film about the evolution of this extreme sport and the sportsmen who play full-contact rugby in Mad Max-style wheelchairs - overcoming unimaginable obstacles to compete in the Paralympic Games in Athens, Greece. The very rugged wheelchairs have wheels angled outward at the bottom for stability. I did create the proper angles with studless beams for this wheel position but felt that the operation would be impaired somewhat for my MDP rover effort. So, to have a more similar Hailfire Droid look...some repositioning of the wheel/slot grapple structure, guide wheels, and alignment/drive gears would be needed. I was surprised at how well it works. Resistance and sound within the drive/wheel support system is barely evident when operating. I planned to add some suspension or flex into the design. Below, I included a picture of an early design with the hoop wheel...the NXT MonoWheel. While it works and can drive, it cannot balance. This was a “just for fun model”. I have been interested in monowheel vehicles since I was a kid. Thank you for stopping to read about history of these creations. Robotics has been a favorite of mine and I hope I have inspired you and other robotics developers to create some wonderful marvels.

Here is the original NXT HoopRover and NXT MonoWheel... 
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This is the revamped HoopRover dressed in the EV3 hardware and a CAD wireframe version... 
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A picture from LEGO Magazine of Astronaut Dr. Daniel Barry with my HoopRover floating above his head like a space station. With a screen grab from the LEGO MINDSTORMS Website.
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