Hi,
There is some possibility or some method to calibrate the PP barometric sensor, because if you compare the PP with many other equipment that I have with the barometric sensor, they all give approximately the same values, since the PP is too far from the correct value.
PP Barometric sensor
Re: PP Barometric sensor
I'm not sure what you mean.
If you mean that the PP starting elevation number is "incorrect", use Isaac Analyze/Analyze Device Settings/Starting Elevation" to correct the starting elevation.
PowerPod does not use absolute elevation settings, but its RELATIVE elevation settings are spot-on.
If you mean that the PP starting elevation number is "incorrect", use Isaac Analyze/Analyze Device Settings/Starting Elevation" to correct the starting elevation.
PowerPod does not use absolute elevation settings, but its RELATIVE elevation settings are spot-on.
John Hamann
Re: PP Barometric sensor
But the PP does not use barometric elevation and pressure to calculate slope percentage, and thus do a watt calculation?
Or how is the calculation of watts done when we go up 8% and that the speed is around 15kms and where we often do not have wind, what factors are used to calculate the watts?
Or how is the calculation of watts done when we go up 8% and that the speed is around 15kms and where we often do not have wind, what factors are used to calculate the watts?
Re: PP Barometric sensor
No, it does not use barometric sensor readings to calculate slope or air pressure.
This is extracted from the FAQ section of the Newton manual, located in the Help section of Isaac. PowerPod uses the same principles as the Newton
HOW DOES THE NEWTON® POWER METER WORK?
The Newton power meter uses a revolutionary approach to power measurement
that is based on Newton’s third law:
“For every action there is an equal and opposite reaction”
In bicycling terms, this means that the factors causing the cyclist to expend power
during a bike ride (hill climbing; opposing wind; tire, bearing and other losses; bike
acceleration) are equaled by the power applied through the pedals by the rider.
With the exception of the Newton, all other high performance power meters
determine power by measuring the forces applied by the rider to the pedal. Directly
measuring applied pedal force is an accurate way to derive power, provided the
cyclist is willing to accept the weight, cost, installation, inflexibility, and operational
penalties that are characteristic of a direct-force power meter (DFPM).
In radical contrast, the Newton uses state-of-the-art sensors, along with new and
patented technology, to measure the opposing forces that cause the cyclist to
expend power: opposing wind, hill climbs, bike acceleration, and rolling friction of the
bike and tires.
A powerful microprocessor, programmed with proprietary DSP filters and real-time
solutions to the dynamic power equation, processes the output from the Newton
sensors many times per second, computing the total power demands created by hill
slope, wind, etc. And thanks to Newton’s third law, measuring the power consumed
by hill climbing, overcoming wind resistance, etc. provides a comprehensive and
accurate measurement of the power generated by the cyclist.
The Newton uses four sensors:
o an accelerometer to measure hill slope and bike
acceleration/deceleration forces,
o a differential pressure sensor to measure wind speed forces,
o an absolute pressure sensor to measure elevation gain, and
o a wheel pickup to measure bike speed.
All sensors except the wheel pickup are located within the Newton housing,
making it possible to use the Newton, quickly and easily, on all of your bicycles.
HOW IS HILL SLOPE CALCULATED?
When you climb a hill your bike’s movement has two components of motion: the
total distance traveled forward on the road, and the vertical distance traveled up the
hill. The “Hill Slope” is the ratio of vertical movement to forward movement,
expressed as a percentage.
Example: You travel 1000 feet forward and climb 100 feet vertically. Your hill
slope is 100/1000 x 100% = 10%
The accelerometer in the Newton measures hill slope instantaneously, much faster
and more accurately than GPS or barometric pressure methods.
HOW ACCURATE IS THE HILL SLOPE MEASUREMENT?
Your Newton uses an accelerometer that measures hill slope and bike acceleration
simultaneously. When your bike is at rest or you ride at a constant speed (in either
case there is no bike acceleration) the hill slope displayed on your screen is very
accurate (within 0.1% of the actual slope). When you are accelerating on your bike
(going faster, coasting on a downhill, or braking) the hill slope may jump around a
bit because the accelerometer not only senses hill slope but bike acceleration as well.
In this circumstance the hill slope displayed on the screen will be only approximately
correct (generally within 1% of actual slope). NOTE, HOWEVER, THAT WATTS ARE
CALCULATED WITH HIGH PRECISION UNDER THESE RIDING CONDITIONS, including
those where the hill slope displayed is “off”.
This is extracted from the FAQ section of the Newton manual, located in the Help section of Isaac. PowerPod uses the same principles as the Newton
HOW DOES THE NEWTON® POWER METER WORK?
The Newton power meter uses a revolutionary approach to power measurement
that is based on Newton’s third law:
“For every action there is an equal and opposite reaction”
In bicycling terms, this means that the factors causing the cyclist to expend power
during a bike ride (hill climbing; opposing wind; tire, bearing and other losses; bike
acceleration) are equaled by the power applied through the pedals by the rider.
With the exception of the Newton, all other high performance power meters
determine power by measuring the forces applied by the rider to the pedal. Directly
measuring applied pedal force is an accurate way to derive power, provided the
cyclist is willing to accept the weight, cost, installation, inflexibility, and operational
penalties that are characteristic of a direct-force power meter (DFPM).
In radical contrast, the Newton uses state-of-the-art sensors, along with new and
patented technology, to measure the opposing forces that cause the cyclist to
expend power: opposing wind, hill climbs, bike acceleration, and rolling friction of the
bike and tires.
A powerful microprocessor, programmed with proprietary DSP filters and real-time
solutions to the dynamic power equation, processes the output from the Newton
sensors many times per second, computing the total power demands created by hill
slope, wind, etc. And thanks to Newton’s third law, measuring the power consumed
by hill climbing, overcoming wind resistance, etc. provides a comprehensive and
accurate measurement of the power generated by the cyclist.
The Newton uses four sensors:
o an accelerometer to measure hill slope and bike
acceleration/deceleration forces,
o a differential pressure sensor to measure wind speed forces,
o an absolute pressure sensor to measure elevation gain, and
o a wheel pickup to measure bike speed.
All sensors except the wheel pickup are located within the Newton housing,
making it possible to use the Newton, quickly and easily, on all of your bicycles.
HOW IS HILL SLOPE CALCULATED?
When you climb a hill your bike’s movement has two components of motion: the
total distance traveled forward on the road, and the vertical distance traveled up the
hill. The “Hill Slope” is the ratio of vertical movement to forward movement,
expressed as a percentage.
Example: You travel 1000 feet forward and climb 100 feet vertically. Your hill
slope is 100/1000 x 100% = 10%
The accelerometer in the Newton measures hill slope instantaneously, much faster
and more accurately than GPS or barometric pressure methods.
HOW ACCURATE IS THE HILL SLOPE MEASUREMENT?
Your Newton uses an accelerometer that measures hill slope and bike acceleration
simultaneously. When your bike is at rest or you ride at a constant speed (in either
case there is no bike acceleration) the hill slope displayed on your screen is very
accurate (within 0.1% of the actual slope). When you are accelerating on your bike
(going faster, coasting on a downhill, or braking) the hill slope may jump around a
bit because the accelerometer not only senses hill slope but bike acceleration as well.
In this circumstance the hill slope displayed on the screen will be only approximately
correct (generally within 1% of actual slope). NOTE, HOWEVER, THAT WATTS ARE
CALCULATED WITH HIGH PRECISION UNDER THESE RIDING CONDITIONS, including
those where the hill slope displayed is “off”.
John Hamann
Re: PP Barometric sensor
I had already analyzed this text, and it was because of him that I came to the conclusion that the barometric sensor was essential, and for that reason it must have been very well calibrated.
"The Newton uses four sensors:
o an accelerometer to measure hill slope and bike acceleration/deceleration forces,
o a differential pressure sensor to measure wind speed forces,
o an absolute pressure sensor to measure elevation gain
o a wheel pickup to measure bike speed."
"The Newton uses four sensors:
o an accelerometer to measure hill slope and bike acceleration/deceleration forces,
o a differential pressure sensor to measure wind speed forces,
o an absolute pressure sensor to measure elevation gain
o a wheel pickup to measure bike speed."
Re: PP Barometric sensor
I'm delighted you looked in the instructions!!!!
The accelerometer measures hills slope and bike acceleration/deceleration forces. This is critical for power/slope measurements
The baro sensor measures the elevation profile (elevation gain) you see in Isaac plots. Elevation profile is NOT used in any power calculations.
The accelerometer measures hills slope and bike acceleration/deceleration forces. This is critical for power/slope measurements
The baro sensor measures the elevation profile (elevation gain) you see in Isaac plots. Elevation profile is NOT used in any power calculations.
John Hamann