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Vehicle Wiring: Actuation Speed Sensing on SPST Switch

purj

Feb 14, 2016
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I want to add a set of auxiliary lights to my motorcycle, and I'd like to integrate their switching with existing hardware rather than add another switch. I need help on developing a solution that accomlishes this. The functionality I have in mind revolves around the high beam switch, and is described as:

A. Vehicle includes low beam light (not involved in this solution, simply noted)
B. Vehicle includes high beam light.
C. Vehicle includes auxiliary light (this is spot/fog light).

N = ~3 (ideally, this should be variable)

1. Vehicle is running, low beam is on (continuous), high beam and auxiliary light are off.
2. User flips high beam switch ON; high beam turns on.
3. User flips high beam switch OFF; high beam turns off.
4. User waits less than N seconds.
5. User flips high beam switch ON; high beam and auxiliary light turn on.
6. User flips high beam switch OFF; high beam and auxiliary light turn off.
7. User waits more than N seconds.
8. User flips high beam switch ON; high beam and auxiliary light turn on.
9. User flips high beam switch OFF; high beam and auxiliary light turn off.
10. User waits less than N seconds.
11. User flips high beam switch ON; high beam turns on; auxiliary light remains off.
12. User flips high beam switch OFF; high beam turns off.

+++

Put another way, from the ON position on the highbeam switch, flipping the switch quickly off then on again changes the status of the auxiliary light's response to the switch, latching and unlatching it with regard to the switch.

If the high beam is on WITHOUT the auxiliary, the user can turn the auxiliary on by quickly flipping the high beam off then on again (high beam is also on after quick-flip).

If the high beam is on WITH the auxiliary, the user can turn the auxiliary off by doing the same (high beam is on alone after the quick-flip).

In all cases where the high beam is on without the auxiliary, if the user turns the high beam off, the auxiliary (obviously, I would hope) remains off. The question here is whether the user then waits less or more than N seconds to turn the high beam on again. If the user waits less than N seconds to turn the high beam on again, the auxiliary comes on with the high beam. If the user waits more, the auxiliary remains off.

In all cases where the high beam is on with the auxiliary, if the user turns the high beam off the auxiliary also turns off. The question, then, is the same as above. If the user waits more than N seconds to turn the high beam on again, the auxiliary also comes back on. If less, the auxiliary does not come back on.

In case this is not clear, the high beam can be on without the auxiliary, but the auxiliary cannot be on without the high beam.

+++

I was wondering if some forum members would be so kind as to offer ideas about a few different approaches to getting this done. Someone mentioned that a 555 timer would be helpful, but couldn't offer any information beyond that. Looking at the 555 page at Wikipedia, I'm seeing a "bistable" mode that looks promising, but I'm not exactly clear on how that would work. I do have some specific design questions deriving from the explanation there, but it seems premature to ask them.

I think this could easily be accomplished with an Arduino, but I don't like the idea of the extra complication and bulk. But I'm open to hearing ideas along these lines.

+++

Thank you in advance!
 
Last edited:

dave9

Mar 5, 2017
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Won't this have to be constantly powered so it's a parasitic drain on the battery when the engine is off? I suppose possibly you could put a capacitor on the high beam circuit to derive the switching circuit power, to give it enough power for "n" seconds.

Frankly it seems excessive relative to just putting in an aux switch for aux lights, and then you don't have to modify the factory wiring. If you ever sell it the new owner is going to be uttering a few curse words when it is observed that the wiring was hacked up, and you need somewhere to put this circuit so it is not like that is any less space taken than a switch for the aux lights, or do you intend to try to conceal the function because it isn't road legal?

The following "might" do it, I'm not sure because I started getting a headache reading it. ;)

https://www.ebay.com/itm/DC-12V-DPD...-Polarity-Audio-Motor-switching-/283277593656
 

purj

Feb 14, 2016
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Feb 14, 2016
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Sorry about your headache, and thanks for the link.

Won't this have to be constantly powered so it's a parasitic drain on the battery when the engine is off?

I don't think so, but that's something to think about.

Frankly it seems excessive relative to just putting in an aux switch for aux lights, and then you don't have to modify the factory wiring. If you ever sell it the new owner is going to be uttering a few curse words when it is observed that the wiring was hacked up, and you need somewhere to put this circuit so it is not like that is any less space taken than a switch for the aux lights, or do you intend to try to conceal the function because it isn't road legal?

The device shouldn't appear within view, the point being twofold: to avoid putting a new switch on the handlebars, and to avoid ergonomics that require me to take my hand off the bar to operate such a switch.

I'm thinking it should condense to a small box attached to the inside of a front fairing. Without knowing the solution, I'm unable to say with 100% certainty, but I anticipate that the only place I will tap into existing wiring is on the hgh beam circuit, to provide the signal that lets the device know when the switch is thrown. I will do this cleanly. Aside from that, I'll be taking power for the aux lights through a new circuit via the accessory fuse box. I anticipate the device will include a relay.

Regarding legality, I take it you know that some aux lights are legal and some aren't. I would be using a set of the former, from Ridig Industries.
 
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Bluejets

Oct 5, 2014
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Make up a truth table, learn how to program an Arduino and go for it.

Could be problems with whatever vehicle registration /insurance you have to deal with though when they find out about illegal/un-certified mods.
 

purj

Feb 14, 2016
47
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Thank you for your concern regarding vehicle registration, insurance and legalities. See my post above for more info.
 

purj

Feb 14, 2016
47
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I wanted to say a little more about my ideas surrounding the 555 and the Arduino.

I know the Arduino approach here would be fairly straightforward. While I'm no expert, I have programmed one before. I can imagine a scenario where each "on to off" event registers a timestamp, then the arduino keeps track of time, then when it sees an "off to on" event, it measures the time, compares it against a set variable, and toggles between high/low on a pin which controls a relay. It may turn out that I go this route with a small-form-factor Arduino and call it good.

But I'm curious to work with the 555 chip, although I imagine it would be more complicated. The insight I can come up with myself in this area is considerably less complete. I know the 555 can send pulses for a set amount of time. I imagine these can be sent in response to a drop in voltage (i.e., when the switch goes off). The problem I have is envisioning the toggle solution. The 555 can give me voltage that endures for a particular time, but what would then compare the change in voltage in one spot (from the light turning on) against a charge in another spot (from the 555 timer which started when the light turned off) and apply a voltage to a third spot (the relay) if the first two spots both have voltage? What kind of component would this be?
 
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