Arduino controlled automatically actuated grill block

[Daox]

I went ahead and ordered the rest of the components. Once everything is here I'll setup a test setup and make sure things work. Ironically, this weekend at the EV meet, there was also an amateur robotics club meet afterwords. I stayed for that as they were doing a presentation and lab on h-bridges! It was perfect, I stayed and messed with them and asked a bunch of stuff.

I also think I'm going to go with a single hinged door. If I can fit a single door on the car, it will be hinged on the top to try and keep snow and ice off the hinged area.

[Daox]

Originally Posted by 93Cobra#2771

Putting it after the rad is perfect, as it gives you right then temps on whether or not there is sufficient airflow through the rad. Not after it makes a trip through the motor and heats up even more. I think this would make for more accurate control.

My concern with mounting it after the radiator would be that it would be very hard to adjust for the cooling effect of the radiator when blocked. I want the grill to open before the fan comes on. If I wait until the coolant goes through the radiator and cools somewhat (which will vary depending on a bunch of things) I'll have no idea what temperature to set the switch open temp to. I'd like my sensor to know the engine coolant temp as soon as the radiator fan sensor, not somewhere farther down the chain. It would seem that putting the sensor after the radiator would create too much fluctuation and lag (vs the radiator fan's temp sensor) than if it was put further upstream.

[Daox]

Originally Posted by lunarhighway

fan switches relays... two which switch the position of the ground and the power line to the actuator. changeing its direction (fan on=extend, off = in) and one wich determines wich controle switch (fan on = monitor pistion full out, fan off = monitor piston full in) is monitored

this controle switch operates a 4th relay that switches the main power off if the pistion is at the end of its travel.

maybe not the most refined system but the logic could be used for something more advanced.

What kinda temp switch are you planning on using?

[lunarhighway]

What kinda temp switch are you planning on using?

i'm not sure i understand the question. the idea is i hook up an extra wire to the fan power line... there's a socket on the fan, so if i can find i male and female connector i can literally "hook up" my addition without any wire cutting. i let all the factory stuff do the temp detection,so when the opel engineers decide things get to hot and the fan comes on the doors are kicked open. the idea is to combine the simple blunt effectiveness of a full grillblock with the "death vally" proof stock setup. allowing a little airflow trough at all times will keep the temp below the treshold 90% of the time so the fan doesn't come on every 5 minutes

that's the theory

[Daox]

Ah yes, I forgot... Too much looking at circuits lately haha. Do you have any idea when you'll build your setup?

[lunarhighway]

i've been working on and off on the thing for the last few months, but other stuff has kept me from tinkering with the car to much.
basically i've got most of the stuff, i've had the door installed on my car to check the fit so now i "just" need to breath some life into it.

so far i've got a more or less working door mechanism for the top grill but the pulley system i'd build looked a little messy... if i had found something to use as pulleys to route the wires i might have gotten it to work, it's not a dead end but if i can find a simpler actuator like that great central locking motor i think that's the way to go

but since i'll start moving next week to my new place wich needs some major (eco) modding i'm a little worried it'll be some time before i get some time to work on it.

btw an old idea just popped back in my head! i'll just mention it for what it's worth.

when i first started thinking of a grillblock i considdered a gradual opening and closeing system...
although i never got very far with the idea the motion of the temp gauge was inspiring... there it was right before my nose something that gracefully moved in relation to the engines temperature!... i assume this is controlled by an analog changing voltage so taping into this signal could be interesting.

mapping voltages to temperatures can give you key points where something should happen (opening angles for the door perhaps)... some relatively simple electronics could trigger a relay at a certain voltage (basically something like that makes the fan kick in...that's maybe how i arrived at that idea)

unfortunately my knowledge of electronics are a little rusty but i remember in school we once build a simple voltage meter where leds representing preset values lit up when that voltage was reached... there was not much more on the print than a couple of resistors and a few transistors...

like i said...just an idea

[Daox]

That may be a future step, and the arduino would definitely provide that flexibility. Its a good idea and it would also be a superior grill block IMO. Baby steps for me though. I'm all new to this.

[Daox]

Alright, I have the physical block and door pretty much designed. I kept it as simple as possible. Its still a bit rough (yes I know the control arm in the 2nd pic isn't attached), but I'll tweak it as it's built. I just wanted a rough idea of how long the L shaped arm needs to be.

The block will be quite easy to mount behind the lower grill on the Matrix. There is plenty of room down there. I'm planning on making it out of coroplast. If reinforcement is needed I'll do that with some .030 aluminum sheet I have.

Anyway, pics!


Closed:



Open:

[tasdrouille]

Is the L arm in the same plan as the grille or am I seeing things out of perspective? Something looks wrong in your linkage. That L arm is going to want to bend sideways during operation. I also don't see how it could possibly close the grille shut at speed.

EDIT: Ok, the arm is probably not in the same plan as the grille. It's lined up with the actuator. I still doubt that little actuator will be strong enough, especially since the L arm gives leverage against the actuator.

[vtec-e]

There is going to be a bending action there at the L-bracket's pivot point. It being a problem should become apparent with trial and error. Perhaps bending the pivot bolt upwards by about 20 or 30 degrees might strike a balance in terms of the pushing force on the door. Or raising the pivot point as far as possible from the door will also lower the bending action enough to let it work (invert the L-bracket to have the pivot point even higher?). A spring might also come in handy to counteract the weight of the door although the door lock is probably plenty strong.
Best of luck with this. I tried this with bike brake cable but it didn't work out.

ollie