elderlybeginner/target_shooting

Measuring precision and accuracy in target shooting (using process centroid, standard deviation and probability)

date: 2019-11-06, last modification 2020-01-05
tags: [Python, shooting, sport shooting, precision, accuracy, measuring, statistics, gauss normal distribution]

Measuring precision, accuracy and probability for Target Shooters

When shooting to target there are two main indicators of how good is your shooting:

1. Precision - the ability to hit the same place over and over. This gives you shot dispersion which I am going to measure with a standard deviation.

Source: public domain

2. Accuracy - is the proximity of results to the center point. I am going to measure it with centroid (X,Y distance to the center)

Source: public domain

The Project

The project is to calculate precision and accuracy based on bullet holes on target.
You are scanning or a take photo of a target, mark holes (how about primary hole recognition?) and the program calculates Centroid (average position of all the holes) which is shown on the target and Standard Deviation (how far you are from the target in average). If you input your expectations (eg. 8 and up in the target), using standard deviation you will get the probability of hitting the target within that limit.

Calculating centroid

Measurement is to be set as the distance from the center to the default place.
Then we calculate holes position as a list of lists:

h1 = [x, y], h2 = [x, y], ... hn = [x,y]
h2 = ...
...
hn = ...

holes = [h1, h2, ..., hn]

and centroid is calculated:

x = [h[0] for h in holes]
y = [h[1] for h in holes]  #  or x, y = zip(*holes)

centroid = [sum(x) / len(holes), sum(y) / len(holes)]

Calculating Standard Deviation and probability

TODO

Visualization

The window is divided on two parts:

1. Setup / Data / Manage

Setup is build of:

• calibrate: button for target calibration (diameter of the target)
• scan: imports scanned target (missed on the drawing)
• find holes: tries to mark holes automatically
• fix holes: you can fix and enter holes by hand
• tolerance: dispersion you are trying to reach
• add text: any notes you would like to add
• date

Data is build of:

• Centroid: which gives info about your precision (X, Y: coordinates where is the middle of your shooting)
• Standard Deviation: which gives info about your accuracy
• Number of holes
• Probability: based on standard deviation, the probability that you shoot withing the tolerance

Stats are build of:

• save result
• load result
• stats: manage all your previous results

2. Target or SD/Centroid (flipped by upper tabs)

In this window, you can flip between target view and history results.

Data gathering

Standard deviation and centroid are gathered and put on the chart to show target shooting progress.

I am a newbie in shooting, dispersion analysis and programming. Feel free to correct my mistakes and give some constructive tips.