My Sun Trip Bike, Back to Back Tandem Trike with Rowing Generator, Pedals, +Solar

Snickers said:
Just, just in time! :roll:
Have a nice trip to France...

Well, we're in France! The flight over trip and and first day was spent catching up on missed sleep from the final build week. We're currently in Paris since there are some final visa details to work out at the embassies here and assuming all goes well then we head to Lyon on Monday to collect all the trike pieces and build it all up again.

I didn't show show how crazy epic the new solar roof turned out. This is what happens when you fit the maximum allowed 550 solar watts for a tandem bike in a single roof structure:
EpicSolarRoof.jpg

It's kindof insane when you see it like that. With the fiberglass on foam construction and the aluminum center brace the weight of the roof substrate without the solar panels is 14.5 pounds. With the solar panels on there it's more like 37 pounds.

As a bit of perspective, on sunny summer days this panel should provide us with about 4 kWhr of energy. Weight of a single 4 kWhr lithium battery pack that could do the same thing? More like 45 pounds.

Obviously a 45 pound battery is a lot easier to fit in an ebike than a 14 foot long solar roof, but it was interesting and surprising to me that the solar comes ahead in this simple daily energy/weight comparison.

We didn't actually test out this new roof build though. We just had time to slap it on the trike in time few media interviews, take a group shot with the Grin team, and then start the dismantling. While it's ungainly standing upright, horizontal on the trike itself it still works OK. It's a tad disproportionate for the underlying structure but at least on round-the-block test rides it still navigates just fine.

TeamGrin with Final Trike.jpg

It was pretty sad to see the build then all reduced to component pieces. Here it is just before packing into boxes. The tandem frame, the solar panels, and the rowing structures each went in their own oversized boxes via airline cargo freight, while the motors, batteries, electronics etc. all went via fedex. Over $2000 in total just for the shipping.

All Dismantled.jpg

I'm really hoping there aren't hiccups at the receiving end in Lyon.
 
Cowardlyduck said:
After seeing you struggling to fit through some tight spots with the last roof, I'm wondering how you are going to manage across several continents with this new giant roof.
Can you quickly/easily disassemble it if required?

Yeah it comes off the trike frame with just 4 attachment screws. So if it did come to that it wouldn't be too hard to unbolt the roof and then separately carry it sideways through whatever passageway is in the way. The roof itself is higher than all the bollards you often need to navigate and weave through on bike paths so it doesn't present any challenges there as it hovers above the obstacle point, but on bridges with narrow sidewalks that's been the main pinch point so far.

Where you see it just scraping on the Alex Fraser bridge here, that's because we had the roof tilted to the left about 15 degrees which increased the width relative to the frame. If the roof was straight up we'd have had several inches of clearance.

Weaving through lanes of slow moving traffic though as I so enjoy doing on a normal ebike? That is no longer on the table :cry:
 
silicium said:
Welcome in France
I'm coming to Lyon and I'm happy to know that I'm going to see your bike!
I wish you a complete bike quickly

Merci pour ça et à bientôt!

I'm really looking forwards to meeting up with all the other teams and checking out their rigs in the coming days too. My plan is to share pictures and details of other builds that I find interesting on this thread, which should help give a bit more visibility for those outside of Europe.
 
Justin,

I am looking at that PV roof, and trying to imagine riding along our scenic two lane roads in central Virginia, which are idyllic for half an hour at a time, until you find yourself next to a propane truck with a logging truck coming the other way.

I wish you all the luck in the world!
 
One of the details of our suntrip participation and sponsorship is that we were going to supply the Suntrip event itself with a batch of "black box" style data loggers that they can install on each of the solar ebikes participating in the race. Their desire was to log the solar charging amps, discharge current, vehicle speed and GPS position of each vehicle for the entire duration of the trip so that afterwords they'd have an exact record for the metrics of each competitor. We realized that this could effectively be done with our existing Cycle Analyst and GPS Analogger products along with some customized firmware to separately read solar charge current.

And so, that's what we made! The CA3 boards were soldered to an old small screen LCD module and we found a Hammond enclosure that perfectly fit this stack of a small LCD, CA3 PCB, Analogger Circuit, and GPS module.

SolarBox Open.jpg

In order to measure the solar charge current, we repurposed the Aux input of the CA as a general current sense signal, where you can program in an effective offset voltage and Amps/Volt gain setting. This makes it really easy to use any of the hall effect style current sensors, which is exactly what we did here, and made it into a stand alone part too:
http://www.ebikes.ca/shop/electric-bicycle-parts/solar/solar-current-sense.html

The net result turned out pretty sharp for the job.
BlackBox Complete.jpg

Unlike the normal situation where the Analogger simply logs the GPS data to an independent file, in this case we decided pipe the GPS data as an input data stream to the CA3 device so that the CA could display the GPS info on the LCD screen too. This had the additional benefit that GPS details could be output from the CA's log stream, and stored in the same log file that is perfectly sync'd and time stamped with the CA's info.

Here's the set of additional screens that are now visible on this databox device. The screens that normally showed just Ah or Wh now show both the battery discharge stats toggling with the solar charging stats. As well, there are 2 additional screens showing nothing but GPS details like the lat-long, and elevation, heading, exact time of day etc.

Solar_StatusScreenRevisions.png

For all those who've wanted a clock on their CA3 device, this finally does it :)

The logged file that is saved now has quite a different data set, starting with a time stamp and including GPS coordinates and solar info, and we've updated our Trip Analyzer web app so that you can upload this single file and it will parse it to get all the route info and show the solar watts and amps in the extended dataset. For instance, here's the log file for a test ride we did last saturday from our shop to UBC and back (getting much of the footage shown in the last video)
http://www.ebikes.ca/tools/trip-analyzer.html?trip=ieY98A
LoggedTrip Screenshot.jpg

It'll take a lot of additional rework of this trip analyzer web app to present multi-day log files in a way that is easier to visualize since the graph data quickly gets quite noisy, but that's something we'll be working on over the summer so that by the time the race is done we'll be able to show and compare all the different solar ebike performances with this tool.
 
Thanks to the amazing efforts of Teklektik over the past several months, we managed to make this customized solar Cycle Analyst firmware databox in a way that could be useable by anyone else doing a solar EV project. Instead of needing two separate amp-hour meters on a solar EV, one on the solar panels and another on the battery/motor controller, you can use your main CA display with a separate current sensor on the auxilliary input. Then you can view and record both the solar charge current and the controller currents from one device.

Solar Elec Screen.jpg

For people wanting to try this out, we have an alpha release of a general solar CA3 code that you can download here:
(unzip the package into a V1.54 setup utility installation folder, choosing to overwrite or skip duplicate files)
https://www.dropbox.com/s/7a2jdtzvtc26xp6/CA3-11a23S.zip?dl=0

This will require having a solar current sensor on the auxilliary input plug of the CA3, and for that we recommend an isolated sensor to prevent any issues with ground reference. Just about any popular hall effect current sensor that will run off 5V power and produce a 0-5V signal can be configured to work, like popular ACS712 device.
https://www.sparkfun.com/products/8882
Or the potted plug and play sensor that we have here
http://www.ebikes.ca/shop/electric-bicycle-parts/solar/solar-current-sense.html

This will mean that you no longer have an analog aux input for on the fly limit adjustments, but you do still have the ability to run a set of digitial aux up/down buttons with this solar code, and for most people having a single adjustment setting is sufficient. In this case, you just need the up button to short the aux signal to Gnd, and the down button to short it to Gnd via a schottky diode to produce ~0.4V.

I've provided versions of this firmware to a several other people doing solar ebike builds outside of the Suntrip too. That includes Mark Havran who was exhibiting a solar ebike at the SF Maker Faire a few weeks ago:
https://www.youtube.com/watch?v=gR80QjH6rxg#t=4h28m47s

One of the handy things about this firmware that you wouldn't get easily with two separate meters is that you can now see your NET watt-hours / mi over the course of a trip, including discharge, regen, and solar energy in and out of the pack. This data toggles with the standard discharge wh/km value. With a solar ebike setup, the goal in general is to come out at the end of the day with a net 0 wh/mi. This picture here is from the CA3 on Mark's solar ebike after his trip to the Fair and associated charging.
Net Solar Whkm.jpg

It's really cool to be able to see that, and I'm expecting to make heavy use of this statistic during the course of the Suntrip, monitoring the net solar wh/km during the course of the day and budgeting our power and distance goals based coming out around zero.

It also does a net amp-hour accumulator, in addition to the discharge and regen amp-hours, which can be useful for those wanting a more detailed energy breakdown.

NetAh.jpg

For people who have a GPS Analogger device, it's also possible to update the CA3 with a firmware that will not only have the solar current sensor, but that will also be able to read and display the GPS data (including time, heading, elevation etc) on the CA screen. This requires doing some hardware modification (soldering jumpers etc.) to the analogger so that the GPS's data ouput signal is sent to the data input line on the CA3's communication plug. If people are interested in this then let me know and I can start a separate thread on the topic explaining how it's done.
 
justin_le said:
That includes Mark Havran who was exhibiting a solar ebike at the SF Maker Faire a few weeks ago

Hey gang,

Mark here. Long time lurker. First time poster. I figure this might be a good time to say hello and offer to answer any questions about my experience so far with the new SolarAnalyzer firmware.

The CA photos above show my stats after having done a 107 mile (172 km) round trip from Oakland to San Mateo and back in one day with only a 400 Wh battery pack. It was mostly cloudy during the 4 hour ride down to Maker Faire and I was only getting 25-50 watts most of the way and then 100-180 watts during the last 30 minutes so I used the Net Wh/mi value to adjust the level of assist on the fly to ensure I didn't hit LVC on my pack before I got to the event. Worked like a charm.

If there's interest in my own solar ebike, I'll start a separate thread for that.

Mark

UPDATE: I've started a new topic about my own solar ebike project.
 
solarEbike said:
If there's interest in my own solar ebike, I'll start a separate thread for that.

Mark
Count me in as someone who is interested.
 
Really love the idea of ditching my separate power meter, but I leave my bike unattended all day every day in a public place so the panel gets good sun to charge the bike.
Would the controller have to be powered on for the CA to measure/record the solar charging current?
I also run a 3 speed power limit switch...would using the AUX input mean I have to ditch that?

Cheers
 
justin_le said:
I'm really looking forwards to meeting up with all the other teams and checking out their rigs in the coming days too. My plan is to share pictures and details of other builds that I find interesting on this thread, which should help give a bit more visibility for those outside of Europe.

Hi Justin, I discovered the suntrip and this thread a few weeks ago, this looks like an awesome project.

As a (French) engineer I'm somewhat disappoointed by the technical details revealed by the suntrip organizers (I know the race is not yet started, so they could still improve their technical covering of the event). I really appreciate the way you help us understand your technical decisions and will follow your trip very tightly !

I'm looking forward to your pictures / technical details / in depth analysis of your competitors 8)

My interest might come to a point where I will be willing to build a solar bike, and all these reviews will be really helpful to make the right decision on the right parameters !
 
Justin and Anne-Sophie made the news!

pic.jpg


http://www.nsnews.com/lifestyle/north-van-couple-commences-epic-bike-trip-using-solar-power-1.23333612
 
Cowardlyduck said:
Would the controller have to be powered on for the CA to measure/record the solar charging current?
No, the controller doesn't need to be powered on, but the CA does so you may need to mod the CA-DP connection if you are powering the CA from the controller. Having the CA active in an unattended situation probably isn't ideal, but I just put in a ticket for discussion of a means to allow the screen to be blanked. No promises, but at least it's on the list for feature discussion later this year.

Cowardlyduck said:
I also run a 3 speed power limit switch...would using the AUX input mean I have to ditch that?
You would need to replace the 3-pos switch with Grin DigiAux buttons or a DIY equivalent as JLE noted above. The DigiAux buttons have a second breakout connector for the regular analogue Aux control - or in this case the solar shunt.
 
Cowardlyduck said:
I also run a 3 speed power limit switch...would using the AUX input mean I have to ditch that?

What teklektic said. :)

I had to give up my nice Aux input pot to be able to connect the Hall solar current sensor. I was a little reluctant to do so but I haven't missed it since I've replaced it with a modified 2 button digital Aux input configured for 0, 1x, 2x, 3x, 4x and 5x assist.

My next build is going to use a set of Harley Davidson handlebar switches and I'm going to set one of the momentary switches (ignition, I think) to simply short the aux signal to ground and set the CA AuxD Control Type to 1 button mode.
 
solarEbike said:
... I'm going to set one of the momentary switches (ignition, I think) to simply short the aux signal to ground and set the CA AuxD Control Type to 1 button mode.
Exactly. This gimmick was called out in a DigiAux document that was pulled from distribution when we switched to Schottky diodes - we never found the time to update the illustrations, etc... Guess that should get back on the ToDo list :wink:
 
solarEbike said:
Cowardlyduck said:
I also run a 3 speed power limit switch...would using the AUX input mean I have to ditch that?

What teklektic said. :)

I had to give up my nice Aux input pot to be able to connect the Hall solar current sensor. I was a little reluctant to do so but I haven't missed it since I've replaced it with a modified 2 button digital Aux input configured for 0, 1x, 2x, 3x, 4x and 5x assist.
Sounds like a good compromise, but I'm not sure it would work out for me. I use the 3 speed switch combined with a reed switch to unlock full power and 2/3 of the 3 speed switch positions. Sounds like moving to the digital switch may prevent this functionality. :(
Maybe down the track an edition of the CA could be released with a separate aux input for tracking charging statistics. That would appeal to more than just solar panel users as I'm sure many would like to track how much juice their charger is putting back into their packs when charging.

Cheers
 
justin_le said:
For people who have a GPS Analogger device, it's also possible to update the CA3 with a firmware that will not only have the solar current sensor, but that will also be able to read and display the GPS data (including time, heading, elevation etc) on the CA screen. This requires doing some hardware modification (soldering jumpers etc.) to the analogger so that the GPS's data ouput signal is sent to the data input line on the CA3's communication plug. If people are interested in this then let me know and I can start a separate thread on the topic explaining how it's done.

Hi, I'm very interested in modding one of my Cycle Analoggers w/gps for this purpose. Correct me if I'm wrong, but if I
1) update a CA 3.1 with this aforementioned special sauce firmware,
2) purchase and install the Grin solar shunt,
3) mod my Analogger to feed the CA,

then my solar e-bike should be state of the art?
count me in on that. I've used the analogger enough for fleet management/data recording & analysis of e-bikes to really want more integration btw CA and the analogger.

Plus, when you have all this unified data coming from the CA stream, it'll be a lot easier to port it through the rx/tx right to a web upload (via raspberry pi zero w/sim card) which could in effect function as an anti-theft gps alert system. However, the primary purpose of that unified data stream for me would be to enable automatic download via home wifi so the user could check their bike's performance from a web page instead of from a usb port on their bike. At that point, you could also remotely check state of charge, shading, estimated range, etc., from the top of your office building instead of on the side of the road where your bike is parked.

Anyways, I'll look for a post regarding modifying the Cycle Analogger. Thank you.
 
the e wind said:
Correct me if I'm wrong, but if I
1) update a CA 3.1 with this aforementioned special sauce firmware,
2) purchase and install the Grin solar shunt,
3) mod my Analogger to feed the CA,

then my solar e-bike should be state of the art?
Yep. The firmware that JLE linked in above is really an in-house development version of early Sun Trip Solar DataBox firmware. After the Sun Trip that version will evolve a bit to become a production release so 'the state of the art' will get polished up and change a trifle.
 
justin_le said:
....
It'll take a lot of additional rework of this trip analyzer web app to present multi-day log files in a way that is easier to visualize since the graph data quickly gets quite noisy, but that's something we'll be working on over the summer so that by the time the race is done we'll be able to show and compare all the different solar ebike performances with this tool.

This would be fantastic!

I'm very interested in the performance of the vehicles and the solar arrays and sadly so very little data is available to the public from the first suntrips.
 
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