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Private Wang Fire wrote:

windu34 wrote:Ive been trying to use a digital brushless servo (very high quality) and feed it signals in the microsecond format in order to get more precision, but it has to be completely in sync with the encoder I am using to measure distance if I want the vehicle to end up exactly where it started (on the centerline). I have one motor controlling rear wheels and the servo is at the front to control steering. I might try to implement a fixed steering system using gears and a high resolution encoder to give me the angle precise to the thousandth's degree instead of my dynamic system because I wont have to worry about receiving interrupts from the distance encoder and attempting to sync with the servo position thus making things much easier. I don't think building a good fixed system is difficult, I'm more so worried about lining it up with the target at competition.
How are you guys aiming your vehicle?

How do you think the fixed system can be made precise enough? I did some math and it seems as if your angle needs to be <.5 the adjust between even the regional distances. I know you can get the angle precisely with the encoder but wouldn't this be small enough to have every run messed up due to mechanical error with your vehicle? 0.5 degrees offset is a close estimate the difference between 0.5m distance increments w/ max wheelbase.

windu34 wrote:

Private Wang Fire wrote:

windu34 wrote:Ive been trying to use a digital brushless servo (very high quality) and feed it signals in the microsecond format in order to get more precision, but it has to be completely in sync with the encoder I am using to measure distance if I want the vehicle to end up exactly where it started (on the centerline). I have one motor controlling rear wheels and the servo is at the front to control steering. I might try to implement a fixed steering system using gears and a high resolution encoder to give me the angle precise to the thousandth's degree instead of my dynamic system because I wont have to worry about receiving interrupts from the distance encoder and attempting to sync with the servo position thus making things much easier. I don't think building a good fixed system is difficult, I'm more so worried about lining it up with the target at competition.
How are you guys aiming your vehicle?

How do you think the fixed system can be made precise enough? I did some math and it seems as if your angle needs to be <.5 the adjust between even the regional distances. I know you can get the angle precisely with the encoder but wouldn't this be small enough to have every run messed up due to mechanical error with your vehicle? 0.5 degrees offset is a close estimate the difference between 0.5m distance increments w/ max wheelbase.

I don't think I'm understanding your question...
A bazinga stated, it Is certainly possible to get angle precision <0.01 and probably even more so.

Private Wang Fire wrote:
I was just questioning whether it's possible; I guess since you both have clear ideas on how to get there, but I don't see how I could build one with the resources I have access to...

Oh and I didn't mean angle measurement, was talking about the actual construction of the vehicle. Wouldn't slight play in any part of your front axle be enough to throw off the angle by 1+ degrees? Impressive if you manage that kind of precision and accuracy on a fixed system though.

Bazinga+ wrote:

Private Wang Fire wrote:
I was just questioning whether it's possible; I guess since you both have clear ideas on how to get there, but I don't see how I could build one with the resources I have access to...

Oh and I didn't mean angle measurement, was talking about the actual construction of the vehicle. Wouldn't slight play in any part of your front axle be enough to throw off the angle by 1+ degrees? Impressive if you manage that kind of precision and accuracy on a fixed system though.

I would recommend using bearings. If you implement them correctly you will have virtually no wiggle room.

dragon_fruit35 wrote:So, I'm new to this event, and I was looking at some motors to get (the ones I have aren't nearly fast enough). Would either of these be okay, or what kind of motor would you suggest (and do I need a motor shield)?

https://www.amazon.com/Traxxas-Titan-18 ... xxas+motor

https://www.amazon.com/Traxxas-3785-Tit ... xxas+motor

Bazinga+ wrote:

dragon_fruit35 wrote:So, I'm new to this event, and I was looking at some motors to get (the ones I have aren't nearly fast enough). Would either of these be okay, or what kind of motor would you suggest (and do I need a motor shield)?

https://www.amazon.com/Traxxas-Titan-18 ... xxas+motor

https://www.amazon.com/Traxxas-3785-Tit ... xxas+motor

Both motors will work well, but if you feel like you need more torque get the higher turn motor, and if you're looking for slightly higher speed get the lower (18) turn motor. You will need a motor shield, and I would recommend this one: http://www.robotshop.com/en/10a-dc-moto ... Akik8P8HAQ

nickWatt60 wrote:So this year we have decided to step it up a notch and use an arduino for our electric vehicle, does anyone have any insight on using an arduino?

windu34 wrote:

nickWatt60 wrote:So this year we have decided to step it up a notch and use an arduino for our electric vehicle, does anyone have any insight on using an arduino?

Ask specific questions. I'm sure we will be able to answer them