It Hit the Hogu. It Didn't Register: How Electronic Scoring Actually Decides

The scoreboard does not move. The referee does not even look up, because there is nothing to look up for: the system did not register a valid impact, so as far as the match is concerned, the kick never happened. Their fighter prods you with a front-leg tap that barely bends your vest, and the point appears. This article explains the machine that just decided your match, because once you know what it is measuring, you can kick for the thing it measures.

Section 01What the System Is, and Who Makes It

Modern WT sparring is scored by a PSS, a Protector and Scoring System. The trunk protector and the head protector carry sensors. The foot protectors the athletes wear, the electronic socks, carry sensors too. A transmitter on the protector sends each registered impact to the scoring computer, and the score appears without a judge pressing anything.

Two systems dominate international competition, and a competitor can meet either one.

Daedo is the older name, in use at the highest level for well over a decade, now in its TK-Strike generation. Its socks detect impacts through sensors built into the foot covering, and its trunk protector reads both the contact and the force of what arrived.

KP&P is the other approved system, used at many Grand Prix and continental events. It works on the same principle, contact plus force read electronically, with its own sock design and its own sensor layout in the protector.

The two systems do not feel identical under your foot. A kick that registers happily on one can fall silent on the other, because the sensing areas, the sock construction, and the calibration differ. Neither is broken when that happens. They are two different measuring instruments, and part of competing on electronic scoring is learning to kick in a way both instruments can read. National and local events sometimes run other approved brands or older generations of the big two, and the same lesson applies a size smaller.

One more division of labour matters. The PSS scores kicks. It does not score punches. A valid punch to the trunk is still awarded by the corner judges, by hand, the way it always was. So a match is decided by two systems at once: the machine for kicks, human eyes for the punch and for the turning-kick bonus confirmations the machine cannot judge alone.

Section 02The Two Tests Every Kick Has to Pass

A kick scores only if it passes both of the system's tests. Most "robbed" kicks fail one of them cleanly.

Test one: contact in the right place, with the right part of the foot. The sock does not sense with its whole surface. It senses where its sensors are, which is chiefly across the top of the foot and the instep area that a roundhouse kick lands with. The protector, likewise, senses across its covered front and sides, the legal trunk target. A kick that lands with the toes, the edge of the foot, or the heel can hit hard and still brush past the sensing geometry of both pieces of kit. A kick that lands on the seam, the shoulder strap area, or high on the chest above the protector's sensing field is a kick thrown at a target the system does not own. The classic case is the slap that scores: a light front-leg kick that arrives flat, instep square on the sensing surface, reads perfectly. The classic injustice is the opposite: a heavy kick that lands a few centimetres off the field or on the wrong surface of the foot, and reads nothing at all.

Test two: force above the level set for your division. The system does not register every touch. Each weight division, for men and for women, has a valid-score impact level set in the software, and an impact below that level is treated as no impact. The level is calibrated per division because a fair threshold for a heavyweight would erase a flyweight's whole game, and a flyweight's threshold would let a heavyweight score by leaning. This is why research on the systems keeps finding the same tension: fixed thresholds per class are a compromise, and athletes at the light end of a class feel the compromise most. Your job is not to argue with the compromise. It is to know that a real kick, with the body behind it and the instep flat, clears the level, while a flicked kick thrown for speed alone often does not.

Pass both tests and the points follow the normal WT values.

Under the current best-of-three rounds format, each round is its own contest: build a twelve-point gap inside a round, or lead when the round clock ends, and the round is yours. Win two rounds and the match is over. The machine's silence in round one costs exactly as much as its silence in round three, which is why the athletes who thrive on PSS sort their registration out in the first exchanges instead of the last.

Section 03Why Good Kicks Go Silent

The foot surface is wrong. A roundhouse that lands with the ball of the foot or the toes, the way a point-stop fighter was taught for years, puts the wrong anatomy on the protector. The sensing kick lands with the instep, the flat top of the foot, laid across the trunk. If your kick was built in a school that rewarded toe-point contact, the system is not punishing you. It is describing your kick back to you, accurately.

The contact is a graze. Spinning and sliding contact, where the foot wipes across the protector instead of arriving on it, spreads the impact over time and area. The system reads a peak, and a wipe has a low one. The same problem catches kicks thrown while retreating: the target is moving away, the foot chases it, and the arrival is a push rather than a strike.

You hit the protector's dead ground. Low on the hip, high toward the collarbone, or around the side past the legal target, the protector is clothing, not instrument. Club sparring treats all of it as "the body." The system does not.

The head kick clipped the wrong part of the headgear. Headgear sensing covers the scoring surface of the head protector. A kick that lands on the face-opening edge or drags across the top can miss the read, and a kick light enough to be safe in the old game can fall under the level in the new one. Head kicks that score are placed, not swung: instep or foot surface square on the protector, with intent.

Your socks and the system are strangers. Sensor socks wear out, get washed into stiffness, and lose sensitivity across a season. A sock that reads on your club's training system may under-read on a freshly calibrated event set. Serious competitors treat socks as consumables with a life, test them in the warm-up area on the event's own equipment when the organisers allow it, and carry a spare pair that has also been tested.

Section 04Kicking for the Instrument

None of this asks you to kick worse. It asks you to kick in the shape the instrument reads, which turns out to be mostly the shape of a sound kick anyway.

Land with the instep, flat and whole, not with a part of the foot. Put the hip behind trunk kicks so the impact peaks instead of spreading. Aim at the middle of the protector's field, not its edges: a kick placed centre-trunk with real force is the most reliable score in the sport. Finish kicks instead of flicking them, because the second half of a kick's travel is where its force lives. And test early in every match: throw one honest back-leg roundhouse in the first exchange, watch the board, and adjust in the direction the answer points. The athletes who look "lucky" with registration are usually the ones who ran that test while their opponent was still settling.

A note for coaches cornering younger athletes: the first tournament on a PSS is a shock, and it lands on the child as injustice. Walk them through the two tests before the event, on the drive there if needed, and the first silent kick becomes information instead of betrayal. The companion guide prints the two tests as a warm-up-area checklist for exactly that conversation.

Section 05Where It Goes Wrong

Blaming the machine and changing nothing. The system is imperfect and it is also the referee you have. Athletes who spend the break between rounds angry at the hogu throw the same silent kick in the next round.

Reaching for power by swinging harder. The usual response to a non-registering kick is a bigger wind-up, which costs the contact shape that was the actual problem. Fix the surface first. Force second.

Training all year on judges and competing on sensors. A club that scores its own sparring by eye teaches flicked, grazing, toe-first kicking and calls it speed. If your athletes compete on PSS, some of their sparring has to be scored the way the machine scores: contact surface, placement, and a force level, called honestly by a coach playing the machine's part.

Treating the two systems as identical. Warm-up time on the event system is worth more than one more tactical talk. Get kicks onto the actual protector the match will use, at match force, before the first bout.

Forgetting the judges still exist. Punches, turning-kick bonuses, and everything the machine cannot see still run through human officials. A game built only of sensor-pleasing taps gives away the punch points and the bonus points that decide close rounds.

Section 06The Companion Guide

This article gives you the knowledge. The companion guide turns it into training. The PSS Scoring Playbook prints the two tests as checklists you can run in the warm-up area, maps the sensing zones of trunk and head protectors for both major systems, gives a kick-by-kick registration test protocol for finding out what your kicks actually read at, and lays out drill sets for rebuilding the contact shapes that score: instep-flat roundhouse work, placed head kicks, and centre-field placement games. It is for competitors moving from judged sparring to electronic scoring, and for the coaches who have to explain a silent scoreboard to them on the day.