Maxi-Phyling Kayak

The Maxi-Phyling is the versatile GPS unit for collecting data in canoe-kayak. Validated by the International Canoe Federation (ICF), it can be used in training as well as in competition. It provides complete feedback on a crew's performance.

The Phyling Kayak app was developed in collaboration with the FFCK (French Canoe-Kayak Federation) and the French Olympic team, and offers a precise analysis of performance indicators specific to sprint kayak and canoe. It gives coaches training feedback through an advanced analysis module to view, compare and process data. The app can also export data as a report or share it directly on training tracking platforms such as Nolio.

Quick start

Setting up the unit on the boat

1. Firmly attach the Maxi-Phyling to the hull of the boat using a 3M-type Velcro strip
2. Make sure the Maxi-Phyling is placed in the direction of travel of the boat

Tip

The Maxi-Phyling can be placed in a waterproof box (such as a food container) to protect it from the elements.

Starting and stopping a recording

1. Turn on the Maxi-Phyling with the ON button (green LED).
2. Press the REC button to start recording (blue LED).
3. Press the REC button again to end the recording (green LED).
4. The data is saved in the Maxi-Phyling and uploaded to the app via USB or Wi-Fi.

Hub and real-time visualization

1. Turn on the Hub; it connects automatically to the Maxi-Phyling.
2. Access the app through the Hub's Wi-Fi connection. On a PC, tablet or smartphone, enter the address http://192.168.1.42 in your browser.
3. Log in with your username and password.
4. Real-time data visualization is available in the Real time tab.

Data processing and export

1. Find your recordings in the Data tab ("New data" button) to associate them.
2. In the Associated data menu, view a recording, create selections and compare several recordings.
3. Export your recordings and comparisons in various formats: PDF report, raw data, CSV format.

Data

The data recorded and calculated by the Maxi-Phyling kayak provides comprehensive information on the paddling cycle, speed and stability of the boat. To let you make the most of this data, Phyling makes the raw data from each sensor available. Phyling has also developed specific analyses to calculate certain indicators.

Sampling rates

Sensor	Frequency
IMU	100Hz
GPS	10Hz

The tables below describe the variables and indicators calculated, as well as how they were obtained.

CSV file data

This data is included in the CSV file that can be downloaded from the app. It consists of time series sampled at 100Hz, including both raw and calculated data. This is also the data displayed as graphs in the app.

Variable	Description	Unit	Calculation
T	Time since the start of the recording	s
gyro_x	Angular velocity around the x axis (boat axis)	deg/s	High-pass filter (fc=0.2Hz, order=5)
gyro_y	Angular velocity around the y axis (lateral axis)	deg/s	High-pass filter (fc=0.2Hz, order=5)
gyro_z	Angular velocity around the z axis (vertical axis)	deg/s	High-pass filter (fc=0.2Hz, order=5)
acc_x	Acceleration along the x axis (boat axis)	m/s²	Raw data
acc_y	Acceleration along the y axis (lateral axis)	m/s²	Raw data
acc_z	Acceleration along the z axis (vertical axis)	m/s²	Raw data
roll	Roll	deg	Obtained by integrating the gyro data (positive when the boat tips to the left and negative when it tips to the right)
pitch	Pitch	deg	Obtained by integrating the gyro data (positive when the bow of the boat rises and negative when the stern rises)
yaw	Yaw	deg	Obtained by integrating the gyro data (positive when the boat turns to port / left and negative when it turns to starboard / right)
acc_z_	Acceleration along the z axis without gravity	m/s²	acc_z - g
gpstimeUs	GPS timestamp in microseconds since 1970	microsecond	Raw data
gpsTimeAccuracyNs	GPS time accuracy	nanosecond	Raw data
longitude	Longitude	deg	Raw data
latitude	Latitude	deg	Raw data
speed_gps	Speed	km/h	Raw data
altitude	Altitude	m	Raw data
heading	Heading	deg	Raw data
nSat	Number of satellites		Raw data
PDOP	Position (3D) dilution of precision		Raw data
D	Distance traveled	m	Calculated using the Vincenty method
speed	Filtered speed	km/h	Obtained from the GPS coordinates (latitude, longitude). Low-pass filter (fc=0.5Hz, order=2)
speed_i	Instantaneous speed	km/h	Fusion algorithm combining the GPS speed speed and the acceleration acc_x
motif_id	Unique identifier for each stroke		Stroke detection based on the acceleration signal acc_x
cadence	Stroke rate in strokes/min	spm	From the duration of each paddle stroke
pic_acc	Acceleration peak	m/s²	max(acc_x) for each paddle stroke
pic_down	Deceleration peak	m/s²	min(acc_x) for each paddle stroke
t_acc	Duration of the acceleration phase	s	T[acc_x > 0] for each paddle stroke
t_down	Duration of the deceleration phase	s	T[acc_x < 0] for each paddle stroke
amp_roll	Roll amplitude	deg	max(roll) - min(roll) for each paddle stroke
amp_pitch	Pitch amplitude	deg	max(pitch) - min(pitch) for each paddle stroke
d_stroke	Distance per stroke	m	Calculated from speed and stroke rate
timestamp	Timestamp since 1970	s	With GPS, a simple conversion of gpsTimeUs; otherwise the Maxi-Phyling time is used

Indicators

Indicators are statistics that characterize an entire selection. In the app, they appear in the "Indicators" table and also on the first page of the PDF reports.

Variable	Description	Unit	Calculation
D_tot	Total distance	m	D[-1] - D[0] over the selection
T_tot	Time		T[-1] - T[0] unless a stopwatch time is provided by the user
v_moy	Average speed	km/h	D_tot/T_tot
v_max	Maximum speed	km/h	max(v)
loss	Loss index characterizing the loss of speed after reaching v_max	%	Area ratio from v_max: 100 * (1 - integral(v[imax:], x=T[imax:]) / (v_max * (T[-1] - T[imax])))
cad_moy	Average stroke rate	spm	moy(cadence)
cad_max	Max stroke rate	spm	max(cadence)
d_stroke	Average distance per stroke	m	From v_moy and cad_moy
n_vmax	Number of strokes to reach v_max
t_vmax	Time to reach v_max	s
d_vmax	Distance to reach v_max	m
t_95vmax	Time spent above 95% of v_max	s
d_95vmax	Distance traveled above 95% of v_max	m

PDF report

The post-race PDF report for canoe-kayak gives coaches a wealth of information to analyze the performance of their boats in training or in competition. It provides indicators as values and graphs, including the stroke rate-speed profile over the whole race, a detailed breakdown of the time spent in the different speed zones, and a division of the race into segments.

Explanations

The Race indicators section provides the key indicators for the chosen selection (here a 500m race, but it can also be an exercise during a training session). The indicators are detailed here.

This chart shows the distribution of time spent in the different speed zones (defined from the maximum speed). The goal is to spend as much time as possible in the speed zones close to the maximum speed.

The race is divided into segments (here 50m each) and the Race split table gives the average values of the indicators over each segment of the race.

Note

You can choose the split distance you prefer in the app.

The boat angles (roll and pitch) are shown alongside the boat's acceleration signal. The more stable the boat (small variations in roll and pitch), the lower the friction on the hull.

This graph shows the evolution of the Speed vs Stroke rate and Distance per stroke vs Stroke rate relationships from the moment the maximum speed was reached.

This table presents the detailed statistics (mean, standard deviation, minimum, median and maximum) of each variable over the whole chosen selection.