Evaluating the Haul

[Walter]

Moving on to determining if our haul is good or not so good.

We've determined that there are two reasons for hauling - increasing line speed and reducing the amount of line we have in the air. Reducing the amount of line that we have in the air can be thought of as haul distance since we've defined haul distance as the distance the line moves relative to the tip guide.

When we evaluate something from a physics or engineering standpoint, we look at the effectiveness and efficiency of what we are doing.

If we want to measure the effectiveness of our haul we measure the actual distance or speed we achieve as a result of our haul. Distance and speed effectiveness are not the same. Having a long haul does not mean we have a fast haul. If our haul is .5 meters long and takes 0.5 seconds, the hauling speed is 1 m/s. If we have a 1 meter haul that takes 1 second, then our hauling speed is also 1 m/s. We have twice the hauling distance but exactly the same hauling speed.

I expect most people are more interested in hauling speed but for now I will look at evaluating the haul from the point of view of distance as well as speed.

The efficiency of our haul is a measure of the output (hauling distance or speed) relative to our input. When we look at the haul our input is the relative movement of our hands during the casting stroke/haul. If our hands move 1 meter relative to each other and that causes our hauling distance to be 1 meter, then our hauling distance with respect to distance is 100%. If our 1 meter of hand movement only results in 0.5 meters of hauling distance, then the efficiency of our haul with respect to distance is 50%. Similarly, if a relative hand movement of 1 m/s results in a hauling speed of 1 m/s then our hauling efficiency with respect to hauling speed is 100%.

Another area I think would be of value is to look at active hauling vs passive hauling. These terms are my own, so I'll explain what I mean. When I speak of active hauling, I am referring to haul distance and speed that results directly from pulling on the line with the line hand. Passive hauling is pulling line through the guides without active involvement of the line hand. This video from Bernd is an example of what I call passive hauling.

https://vimeo.com/59805806

I think we will see that since there active and passive components to the haul we can try to evaluate the effectiveness and efficiency of the haul by looking at what the line hand is doing only but in order to fully evaluate the haul we need to look at a holistic approach. In addition to considering the basic physics or geometry of the hauling actions of our hands we will eventually also need to consider movements of the rest of our body as well in order to avoid body blocking and other issues. We also need to consider the motion of the rod (translation and rotation) as well. That will also lead us to find that some hauling actions may be effective and/or efficient when single hauling but not well suited for double hauling and vice versa.

[Paul Arden]

Hi Walter,

How do you think speed vs acceleration plays into this? Obviously we are looking for an increase in line speed to occur. But acceleration is also going to have an effect (can be beneficial or problematic) on rod bend. For me this is largely secondary, however while retarding/controlling the rod tip as it unloads may be beneficial, putting a dip into the rod tip path is generally not.

Cheers, Paul

[Walter]

Good question Paul.

In the past it was believed that hauling was all about adding extra bend to the rod but now we tend to ignore that and concentrate on the increase in line speed. The haul can and does increase the bend in the rod.

I think it will be similar to power application during the casting stroke. An uneven application of power leads to tailing loops. We’ve seen demos of this in other posts on the board. One of the most memorable for me was having one person casting while another executes the haul.

It’s a common idea that peak hauling speed should occur at peak tip speed for maximum overall line speed but is that really true given that the haul delays rod unloading and tip speed will keep increasing during rod unloading meaning that maximum tip speed will occur around rsp? Should we be looking for max hauling speed to occur at maximum rod load? That may lead to some interesting discussion because it would indicate that the energy stored in the rod has more impact on the cast than we like to believe. Back to the rod as a bow and arrow concept.

[Walter]

With regards to looking at acceleration and not just speed - absolutely. The bend in the rod is a measure of the force the rod is applying to the line at any point in time. Since F=ma…

[Merlin]

Hi Walter

There are something like 6 threads opened on hauling at this time, for something which has already been studied in the past, an example:
http://www.sexyloops.co.uk/theboard/vie ... 242#p75242

I wonder if this is not a bit too much.

Merlin

[gordonjudd]

Another area I think would be of value is to look at active hauling vs passive hauling.

Walter,
The haul hand path that we can produce with the back cast haul tends to take advantage of of the "passive" haul speed that is associated with the rotation of the stripper guide. I do think that speed could be enhanced by using a haul hand path that more horizontal and in the opposite direction the direction the stripper guide is moving rather than using the up and down path that I see in most caster.

Henry Mattel's path shown in yellow is the exception with its more horizontal path at the point the very high max haul speed (14 m/s) is produced in this cast.

On the forward cast most people use a hauling path that is in line with the butt of the rod and thus do not incorporate the speed of the stripper guide in their cast.

I am wondering if Gunter Feuersdtein is not on to something with the unusual haul hand position in this fishing cast that will take advantage of the stripper guide rotation on the forward cast. I would like to see a high speed video of the haul path he uses on a fishing cast and see how much haul speed he tends to produce with his unconventional approach.

Gordy

[Walter]

Moving along with some initial analysis of the haul distance and speed. In this post I'm going to look at a passive haul due to rod rotation only. I'll use the following diagram to explain the analysis.

I've shown the passive haul in two scenarios. In scenario A, I start with my rod and line hands together and rotate the rod at the rod hand (rotating at the wrist basically). In this scenario nothing exciting happens so we will ignore it.

In scenario B, I've done the same rotation of the rod at the rod hand but with the line hand beginning at the stripper guide and staying in place. Given that the distance from the rod hand to the stripper guide is 1 unit this results in a passive haul distance of 1.4 units. I've only shown a rotation of 90 degrees. If we consider the rod hand the center of rotation the line hand and stripper guide will be two points of a circular path and the line between them will be chord of that circle. The formula for the length of that chord is 2 x radius x sin(angle of rotation/2).

Carrying on with this scenario we want to determine if there is an angle or rotation that optimizes hauling speed. In the following analyses I've increased the amount of rotation to 180 degrees. In the first part of the analysis, I considered constant angular velocity, i.e. the angle of rotation is some constant x time. For simplicity I used 1 for the constant making the formula for the chord length based on time
f(t) = 2r sin(t/2). Differentiating with respect to time gives the formula 2r cos(t/2)/2 or just r cos(t/2). This gives us the following plot:

Haul vs angle constant angular velocity.jpg (35.95 KiB) Viewed 331 times

We know that we don't cast with constant angular velocity. It has been suggested that constant angular acceleration is the goal we should be reaching for (to be debated separately). In the next plot I have arbitrarily chosen a total time of rotation for 180 degrees of 0.5 seconds. In order to accomplish a 180 degree rotation in 0.5 seconds I calculated the value for angular acceleration to be 25.13 radians per second per second leading to a final angular velocity of 12.6 radians per second.

My formula for chord length (haul distance) vs time becomes f(t) = 2r sin(0.25 a t^2) where a is angular acceleration. Differentiating with respect to time gives us the formula for haul speed atr cos((at^2)/4) resulting in the following plot:

haul vs speed constant angular accel.jpg (46.86 KiB) Viewed 331 times

Peak hauling speed occurs at roughly 75 degrees at around the 0.32 second mark.

This is totally unreviewed, of course, so if anyone wants to verify the math that would be welcomed. I can give more detail on the derviation of the equations if desired.

[Walter]

I am wondering if Gunter Feuersdtein is not on to something with the unusual haul hand position in this fishing cast that will take advantage of the stripper guide rotation on the forward cast. I would like to see a high speed video of the haul path he uses on a fishing cast and see how much haul speed he tends to produce with his unconventional approach.
Gunter_Feuersdteins_haul_angle.jpg

Gordy,

Thanks for that. Maybe my recent post will help further that reasoning along. I'm taking the approach of looking at what each hand is doing separately and hopefully we can integrate the parts together later. I look forward to your comments.

With respect to GF's haul, he would be even more unconventional if he held the line against the rod butt with his rod hand during his hauling action. It would double his hauling distance.

It certainly works, but I wonder if this particular hauling action is more suited for a single haul rather than a double haul.

As usual, there are mechanical and biomechanical issues to consider. I'm hoping we can get there eventually.

[Walter]

Merlin,

You'll be happy to know that I intend not to create any more threads for a while. At least until we get to discussing the biomechanical aspects.

[John Waters]

Another area I think would be of value is to look at active hauling vs passive hauling.

Walter,
The haul hand path that we can produce with the back cast haul tends to take advantage of of the "passive" haul speed that is associated with the rotation of the stripper guide. I do think that speed could be enhanced by using a haul hand path that more horizontal and in the opposite direction the direction the stripper guide is moving rather than using the up and down path that I see in most caster.

Henry Mattel's path shown in yellow is the exception with its more horizontal path at the point the very high max haul speed (14 m/s) is produced in this cast.
max_haul_speed.jpg

On the forward cast most people use a hauling path that is in line with the butt of the rod and thus do not incorporate the speed of the stripper guide in their cast.

I am wondering if Gunter Feuersdtein is not on to something with the unusual haul hand position in this fishing cast that will take advantage of the stripper guide rotation on the forward cast. I would like to see a high speed video of the haul path he uses on a fishing cast and see how much haul speed he tends to produce with his unconventional approach.
Gunter_Feuersdteins_haul_angle.jpg

Gordy

Hi Gordy,

Is it possible to identify the maximum velocity of Henri's rod hand on both the final back and the delivery cast?

Thanks in advance,

John