Kicker Effectiveness

[Sunny]

So...after just looking at what we have today, here's what I've determined.

A) We're hitting the ball too low. It's getting a decent arc, but it has too much upward velocity. The easiest way to fix this would be to move the kicker Point of Rotation back.

B) I also feel like our kicker is not following through as well, and I think I can blame that on the shape of the kicker. The kicker needs to have more of a "face" of kick and less of a "point" of kick. Maybe add a bit of plexi or 90 degree metal that cuts across the front of the angle gussets.

c) We can always increase the tension in the tubing a little bit, but I think we'd see more powerful kicks if we move the tubing closer to the point of rotation. Why? Well, my thought process (please correct me if I'm wrong), is that yes the tubing will lose leverage, but it will gain speed. So where it used to follow through at a speed of x, it'll now follow through quicker if we move the tubing closer to the POR(Point of Rotation).

D) The kicker looks a little warped because one of the ends are starting to come apart, but it will be tightened tomorrow.

[Tanner]

A) We're hitting the ball too low. It's getting a decent arc, but it has too much upward velocity. The easiest way to fix this would be to move the kicker Point of Rotation back.

Couldn't you also solve this by moving the point of "kick" (i.e. the toe) up?

B) I also feel like our kicker is not following through as well, and I think I can blame that on the shape of the kicker. The kicker needs to have more of a "face" of kick and less of a "point" of kick. Maybe add a bit of plexi or 90 degree metal that cuts across the front of the angle gussets.[/quote

Agree. Toe's not exactly big enough.

c) We can always increase the tension in the tubing a little bit, but I think we'd see more powerful kicks if we move the tubing closer to the point of rotation. Why? Well, my thought process (please correct me if I'm wrong), is that yes the tubing will lose leverage, but it will gain speed. So where it used to follow through at a speed of x, it'll now follow through quicker if we move the tubing closer to the POR(Point of Rotation).

That makes sense to me. It might take a bit more tubing, but it does make sense.

I also noticed a missing screw on one of the triangles on my frame, which will also need fixing.

Overall, I think it worked well. Bit more tuning and it should be kicking like Dad's. I think I can get a PID loop on the kicker so it can hold it's position in cocked mode a bit better. If that doesn't work I can say just do 10% power instead of 0 when it's holding on. Either way, both would work.

-Tanner

[freds]

Sunny, i agree there are some issues. We need more 'kick'. I think the current foot is only extending an inch or so, so not really impacting the ball. I think the kicker has the force, just not enough impact. Make the toes longer or reposition as needed while keeping ground clearance over the bump.

[Tanner]

We should see where the ball is impacting the kicker by like pushing a ball up to it and see where's it is hitting with no tension. Using that we could decide what to do depending on how much room we have under the robot (which I think is like a inch or two).

-Tanner

[Sunny]

Sunny, i agree there are some issues. We need more 'kick'. I think the current foot is only extending an inch or so, so not really impacting the ball. I think the kicker has the force, just not enough impact. Make the toes longer or reposition as needed while keeping ground clearance over the bump.

I agree that the foot probably needs to come out a bit...but the other issue is the surface area with which we are currently kicking the ball.

If a soccer player kicks a ball with his toes, then the ball will generally go straight, but with little speed. If the same player straightens our his foot and then kicks the ball with the surface area of his foot + angle, the ball will often have great force and has the potential to travel the length of the field. Likewise, I believe the kicker that you made had the flat piece hitting up against the ball, and that's why it was so successful.

So making the toes "longer" might not help as much as maybe creating a flat point of contact between the ball and the kicker.

Sunny

[freds]

Sunny
We need to look at the shape of the kicker. Take a look at the 'coceador de madera'

We are not getting the 3" in front of the frame as we need to add some foot or toes. Leddy suggest a solid front vs individual phalanges. My suggestion is we add a solid 80/20 bar mounted to the kicker piece using those pivot type pieces so we can manually adjust the angle of the toe bar.

Also, this may effect the ground clearance when in the 'cocked' position. We may have to angle the top piece that we pull back on to get more distance.

Sunny and Kapp need to focus on this.

[Tanner]

We need to look at the shape of the kicker. Take a look at the 'coceador de madera'

Is that a horse or a kitchen appliance? Google doesn't give a exact answer.

-Tanner

[Sunny]

Getting the 3" in front is not as key as getting the initial contact in the ball.

Conservation of momentum states that in the impact between the ball and the metal bar, the ball will have a faster speed, and when the kicker reaches its perch outside of the robot, the ball has already cleared it.

And to increase the leg length of the kick, we would have to *raise* the point of rotation, because the height at which the kicker hits the ball is semi-fixed.

Pretty much it's more and more tweaking.

[freds]

You might be right, but why are tennis, golf, baseball players always trained to follow through when hitting a ball with an object. There is no doubt that the follow through assists the 'hit'.

[Sunny]

You might be right, but why are tennis, golf, baseball players always trained to follow through when hitting a ball with an object. There is no doubt that the follow through assists the 'hit'.

You pose a good point in the follow through, but I think that's more to simply get the full strength of the swing and proper "form." A well practiced follow through allows the hitter/golfer/tennis players to channel more force into their swings without damaging/putting too much strain on their arms/upper torso.

And if you look at a slow motion footage of a baseball player hitting a bat, you can see that the ball hits the bat at one point in the bat's motion, and then rest of the swing has little affect on the ball.

Of course, the above is just my most educated guess. I'll try and talk to Mr. Leddy/Landers on the topic tomorrow and get back to you.