Information and control panel for a recumbent trike

Trike Rider

Greetings to the forum, I have been lurking for the last several years and have decided to finally make the plunge.· I have been active in electronics my whole adult life, worked with Basic Stamps and Microchip Pics.· Have programmed in Basic, C, and assembler.
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The project I am contemplating is a control and information system for my recumbent tadpole trike, Rayman’s displays are the trigger that I think might make this possible (or at least enjoyable).
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Main power will be at least 8 AH of battery at 12v plus, would like to be able to charge from mains and have some real time status of battery condition on the control panel.
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Main lighting will consist of high power LED’s driven at 1 amp or more to generate better than 600 lumen, rear flashers in the 100 lumen range, would like to generate various flash patterns and dimming ranges.· All controlled by touch display.
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Sensors:
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GPS – 5 hz or better update rate, for position and a sanity check on some of the other inputs.
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Barometric -· Maybe two, would like one altimeter, and another to run pitot tube for air speed.
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Compass -· Might talk myself out of this since GPS will give the same info but would be nice to have.
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Inclinometer – When combined with wind speed and trike speed should be able to generate a power meter function.· If I can get enough precision on altimeter I should be able to calculate this, but a good straight forward sensor would be nice.
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Temperature – Should go hand in hand with barometric.
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Cadence – Magnet on the crank arm.
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Speed – Probably use GPS, wheel sensor would be more accurate and update quicker but awkward to install on trike ( maybe wireless? Ant+?).
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Gear Indicator – The trike has a very straight forward transmission, I should be able to calculate based on cadence and speed.
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All of this wrapped in a nice GUI and based on Rayman’s displays and of course driven by a Prop.
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Any input on a board for development ( I have none now ), objects, sensors, suggestions in general.

SRLM

DIY drones has an airspeed sensor that might work for you (with pitot tube) and Sparkfun has a 5Hz GPS that I've used and like.

Trike Rider

Thanks SRLM

Looking at the SCP-1000 for altimeter, need a two port for air speed.

jazzed

Welcome to the forum.
Can't you use a hall effect sensor and a magnet to determine speed and Propeller CNT ?
Obviously ground speed is different from air-speed, but looks like that is being solved.

Post Edited (jazzed) : 11/2/2009 7:03:59 PM GMT

David B

Are you going to want to log anything or is this all for current-time display?

Wouldn't you want to display the time? GPS can provide this but you'll probably have to provide your own local time/daylight savings conversion routine to show local time correctly.

It might be nice to have an automatic shutdown if the battery charge gets too low. This item http://www.pololu.com/catalog/product/751 came up in another thread; I've never used it but it looks handy.

It might be nice to have the system automatically turn the lights on when it's dark enough and off at daytime. I bike to work from before dawn sometimes, and it's easy to forget that your lights are on after the sun rises.

I'd suggest you get a propeller protoboard, a prop plug and a power supply. Those will be enough to get started with the simple "flash an LED" project, after which you can start adding accessories as you build up experience.

The prop would be great for this. All you need to do is kick off cogs to monitor external sensors and write to different hub locations for each sensor, then a main spin program can just sit back and read off the current hub values to build the full display. Not that it's really so simple, but the multiple cogs really make life much easier when you need to monitor multiple sensors.

Trike Rider

jazzed said...
Welcome to the forum.
Can't you use a hall effect sensor and a magnet to determine speed and Propeller CNT ?
Obviously ground speed is different from air-speed, but looks like that is being solved.

Thanks jazzed, that is the traditional way of doing it, the way the trike is layed out makes wheel sensors awkward and I am trying to avoid running cables everwhere, but the very fine resolution that you have when going this route will probably make it worth it.

Trike Rider

David B said...
Are you going to want to log anything or is this all for current-time display?

Wouldn't you want to display the time? GPS can provide this but you'll probably have to provide your own local time/daylight savings conversion routine to show local time correctly.

It might be nice to have an automatic shutdown if the battery charge gets too low. This item http://www.pololu.com/catalog/product/751 came up in another thread; I've never used it but it looks handy.

It might be nice to have the system automatically turn the lights on when it's dark enough and off at daytime. I bike to work from before dawn sometimes, and it's easy to forget that your lights are on after the sun rises.

I'd suggest you get a propeller protoboard, a prop plug and a power supply. Those will be enough to get started with the simple "flash an LED" project, after which you can start adding accessories as you build up experience.

The prop would be great for this. All you need to do is kick off cogs to monitor external sensors and write to different hub locations for each sensor, then a main spin program can just sit back and read off the current hub values to build the full display. Not that it's really so simple, but the multiple cogs really make life much easier when you need to monitor multiple sensors.

Thanks David B, because the trike is low to the ground and hard to see I try to run some kind of daylight running lights the more flash the better.· Rayman keeps hinting about a board that will directly interface to his displays that sounds interesting.· You would go with a protoboard over a demoboard?·
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David B

I would think that for a runtime version you'd want to solder your connections, which is why I thought of the protoboard.

But if you can afford it to buy several boards, the demoboard sure would help make experimenting easier as you build up the project on your desktop.

Or you may wind up like many of us here, with homemade boards, and demo boards, and protoboards, and a couple of spinStudio boards, and a few extra propeller chips, just in case. This controller can be addicting!