Beginners: please read this post and this post before posting to the forum.
0 Members and 1 Guest are viewing this topic.
I'm not building a robot per se, but I think learning about robots and sensors will help accomplish my goal. I want to build an auto-cancel system for the turn signals on my 2012 Honda CBR1000RR.Normally, after completing a turn, one must remember to turn off the turn signal. Some bikes come with this feature, but most don't. Mine didn't, and I thought it would be a fun project to make one.
There are some store-bought solutions, but they are just essentially timers with various modes. I think a timer is a lame solution.
Self cancelling signals on a motorcycle are a bit of a tricky problem:
1) You can't rely on handlebar position sensing, because of the way motorcycles turn a) The bars don't turn very much at all except in low speed corners
b) Because of the way motorcycles work, each steering "event" is preceded by a counter-steer (this is what leans the bike.)
2) Detecting lean is tricky because the turning force is essentially down through the centerline (a mercury switch won't work reliably.)
I tried experimenting with a heading hold gyro (out of one of my model helis) and due to drift etc, it doesn't really provide a reliable output I could use to flip a switch or delatch a latching relay or something.
I've done a bunch of searching to try to learn a little about what sensors might suit this application. My thoughts on a solution:1) I don't know how to build robots (yet) or write code.
2) I don't want this to cost more than, say $100.
3) A distance-traveled system would probably work as long as it was fairly accurate.
4) A compass heading system might work too, as long as the compass can work reliably when mounted in a motorcycle (vibration, interference, lean?)
5) If there was a reliable way to sense lean angle without sensor drift, that might work.
6) If a gps sensor could be used to determine distance, that could work, but I think gps sensors might be too expensive.
A couple of questions for the experienced folks:1) Is there a sensor that could be mounted underneath the bike that would "view" the road surface and determine distance traveled? When car magazines test cars they have a device like this. It looks at the road surface and somehow measures speed.
2) Is there a way to use an accelerometer and not have it be "fooled" by the fact that the bike leans in turns, thereby creating a false "UP?"3) Can a compass sensor be mounted under the seat or somewhere hidden and still function properly?
The basic output I would need would be a logic high or low that I could use to reset a circuit or unlatch a latching relay.
Hi,Strange... Of the five MCs that I've owned, the two rice burners did have this and even a Honda CD50 I had as a teen was equipped the same way.
And yet, they managed to make them semi-reliable back in the seventies?Can't be that hard, given the progress of technology since then.
Quote from: kenkamm on September 05, 2012, 03:12:12 PMThere are some store-bought solutions, but they are just essentially timers with various modes. I think a timer is a lame solution.Ahemmm... Are you going for form or function here?
Quote from: kenkamm on September 05, 2012, 03:12:12 PM1) You can't rely on handlebar position sensing, because of the way motorcycles turn a) The bars don't turn very much at all except in low speed cornersThey turn plenty to detect it.
Only the more abrupt turns and only up to a certain speed, you need counter-steering...[snip]
Quote from: kenkamm on September 05, 2012, 03:12:12 PM2) Detecting lean is tricky because the turning force is essentially down through the centerline (a mercury switch won't work reliably.)That's not completely true - Try bolting a glass of water to your bike and go for a drive - if your statements holds water, so does the glass
Quote from: kenkamm on September 05, 2012, 03:12:12 PMI tried experimenting with a heading hold gyro (out of one of my model helis) and due to drift etc, it doesn't really provide a reliable output I could use to flip a switch or delatch a latching relay or something.Did you try a 3-axis accellerometer?Quote from: kenkamm on September 05, 2012, 03:12:12 PMI've done a bunch of searching to try to learn a little about what sensors might suit this application. My thoughts on a solution:1) I don't know how to build robots (yet) or write code. Not knowing your time frame or whether you want to build other stuff, I'd stay off microcontrollers then - too much to learn for just a single use.
Quote from: kenkamm on September 05, 2012, 03:12:12 PM2) I don't want this to cost more than, say $100.For how many
Quote from: kenkamm on September 05, 2012, 03:12:12 PM3) A distance-traveled system would probably work as long as it was fairly accurate.Well, it's the exact equivalent of a timer paired with your velocity
Quote from: kenkamm on September 05, 2012, 03:12:12 PMThe basic output I would need would be a logic high or low that I could use to reset a circuit or unlatch a latching relay.Personally, I'd rip out the relay and make a fully electronic solution, but different folks...
I'd guess the 2012 version of the Gold Wing has got an odometer pulse that you could tap into.
Quote from: Soeren on September 05, 2012, 10:39:51 PMOnly the more abrupt turns and only up to a certain speed, you need counter-steering...[snip]This statement is false, but I'll let you slide on this one because I agree that it could be handled by logic.
It's a CBR 1000RR,
but yes, I did a little bit of research and there is a "0 to 5V pulsed output" that is used to signal the odo. I like the idea of using this to turn off the signals after counting a certain number of pulses. That way, if I'm sitting at a stop light for a few minutes, the signal will remain on. If I signal a lane change on the highway, it will still turn off even though the handlebars move very little. Ideally perhaps I would include a timer to make sure the signals stay on for at least, say, 5 seconds unless I manually cancel them with the stock switch.Any thoughts on best ways to count pulses?