Kinetic measurement · Recorded on your phone

The feet keep the score. Your phone can read it.

We live in a straight line. The court asks for 360 degrees. Film one rally in slow motion from behind the baseline, and FWRK measures every step: your symmetry, your split-step, your return to centre. Then the video is let go. Only the geometry stays, so you can reclaim your full range and keep it for a lifetime.

Access the free pilot now Watch it measure
Topography of FlowRead from one phone
A B C D NETBASELINE PHONE · 2–3 M HIGH◌ SPLIT STEP
Left Right Calibration point

1

Phone, on a tripod behind the baseline. That is the whole kit.

240

Frames a second in slow motion. Every one is read.

4

Court corners to mark. The painted lines become your ruler.

0

Videos kept. Each clip is read, then let go.

The instrument is already in your pocket.

The method · Four steps

  1. 01

    Set the phone

    On a tripod two to three metres high, centred behind the baseline. Height keeps both feet visible between the legs.

  2. 02

    Film in slow motion

    120 or 240 frames a second, in good light. One drill or one rally per clip, under thirty seconds.

  3. 03

    Mark the court

    Touch the two baseline corners and the two service-line corners. The court is redrawn over your clip, so you can see it sits on the painted lines.

  4. 04

    Read the archive

    Both feet are found in every frame and placed on the court. Ten seconds at 240 fps is 2,400 readings.

The Lab · Proof of concept · Simulated rally · 120 fps

Watch a rally become geometry.

A virtual phone films a player on a court of true dimensions. FWRK sees only where the feet are in each frame, and recovers position, steps, split steps and speed from that alone. Step through the five stages to see what each one adds.

Camera view

iPhone, tripod 2.5 m, behind baseline
0.00 s

Topography of Flow

plan view · metres
Left foot Right foot Split step

Movement speed

m/s · tap to jump

Step ledger

most recent first
Time Foot Type Length Airtime Foot speed
From simulation to the court

Measure it for real

The pilot runs this same logic on your own slow-motion clips. Only the source changes: your phone instead of a simulation. These checks tell you the measurement holds.

One afternoon on court
  1. Film three slow-motion clips: a sideline-to-sideline shadow drill (5 reps), a split step plus first step drill, and one live rally.
  2. Walk the baseline slowly once. After calibration it should read 8.23 m (singles).
  3. Measure each clip in the pilot and export the step ledger.
  4. Count the steps by eye in slow motion and compare them with the ledger.
The measurement holds when
  • The baseline walk reads within 15 cm of 8.23 m.
  • The step count is within 10% of your own count.
  • Every split step in the drill clip is catalogued.
  • The same drill, repeated, gives speeds within about 5% of each other.

This is a simulation, so it reads cleaner than real footage. Real clips add motion blur and moments when a foot is hidden. The far side of the court, toward the net, is always the hardest to read from one camera.

Privacy, by design

We read your video. We never keep it.

Your clip is measured frame by frame, then let go. What stays is the geometry: where your feet landed, and when. Never your face, your club, or the people on the next court.

  1. 01

    Read, never stored

    The video is measured and discarded. It is not saved to your archive or anywhere else.

  2. 02

    Only numbers remain

    Positions in metres, timings in milliseconds. Nothing that shows who you are.

  3. 03

    Yours to keep or delete

    Download your steps, positions and archive file whenever you like. Delete them whenever you like.

The Manifesto

The racket takes the glory. The feet keep the score. We live our lives in a straight line, but the court demands 360 degrees.

Tennis is a brilliant, brutal demand on the human foundation. FWRK was built to measure the invisible geometry of that effort. A single phone stands quietly behind the baseline, reading your symmetry, your rhythm, and your flow into the Movement-Archive.

We do not count steps. We measure how beautifully you absorb the earth. Because when your movement is balanced, impact becomes harmless. When your feet stay light, time slows down. The preservation of your foundation is the preservation of your game.

Move beautifully. Play forever.

The Movement-Archive™ · Kinetic Profile

Six readings from every clip.

Instrument Ledger No. 01

I. Symmetry & Poise

Left against right

Compares the count and length of steps on each side, scored to 100. It shows which side is carrying the work.

II. Applied Force

Your fastest movement

The peak speed of the centre of your stance, in mph and m/s, read as Measured, Assertive or Explosive.

III. Temporal Rhythm

The split-step, timed

Milliseconds from your split-step landing to your first full step. Every split step is found and catalogued.

IV. Ground Covered

The path, in metres

The distance travelled by the centre between your feet, with the average length of each step.

V. Return to Centre

Coming home

Seconds from stopping wide, beyond 2.4 metres, to standing within 0.8 metres of the centre mark again.

VI. Taxonomy

Every step, named

Lateral, crossover, recovery, forward, back and split. The balance of lateral to linear is the shape of your game.

The Footwork Index™

84Sample reading

Not how much you moved. How well.

Six readings, one number from 1 to 100.

The Footwork Index draws the readings together into a single measure of movement health. It rises when your sides are balanced, your split-step is quick, your range is wide, and you return to centre without hurry.

Read it after every session. Watch it across a season. It is the number that tells you whether your foundation is being preserved.

What the archive preserves.

01 · Geometry of Effort

Every rally draws a map.

Footprints and a heatmap on the court, read from above. See where you go, where you never go, and the path you take back.

02 · Temporal Rhythm

The split-step, in milliseconds.

The elastic bounce of youth is a timing, not a feeling. Measure it, practice it, keep it.

03 · Bilateral Harmony

Balance is what makes impact harmless.

When one side carries the load, the joints pay. The archive shows you which side, so you can bring them back together.

The Pilot · Open now

Bring one rally. Leave with your geometry.

Founding members measure with the Movement-Archive pilot first, help shape the Footwork Index, and keep every archive they make.

You need
A phone, a tripod, a court
Your video
Never saved

Pilot readings come from a camera-based pose model. Expect several centimetres of error near the baseline and more toward the net.

Open now

Your first rally is waiting to be read.

Access the free pilot now

Film on your phone. Send one clip. Read your geometry.