- Keo Power is a collaboration between Look and Polar.
- The piece attaching to the back end of the pedal spindle transmits the signal to the head unit.
- The power measurement hardware is concealed within the axle.
- These pieces can only transmit to Polar's 500 or 600 series computers.
- These pieces much be fixed perpendicular to the crank arm using a pair of tools and a fairly simple multi-step process.
- The arm of this tool has to be oriented parallel to the crank arm for the system to measure accurately.
- When fixed in place with the Allen key, an 18mm box wrench is used to tighten the pedal axle into the crankarm.
- Accelerometers used to measure pedal velocity.
- Keo Power is only compatible with their 500- and -600 series computers and no others.
- Garmin Vector has accelerometers in the silver piece to monitor cadence, which is used to calculate power in conjunction with the strain gauges in the spindle.
- Garmin Vector will be out in March.
- ANT+ compatible transmission allows it to communicate with Garmin computers and any other with the ANT+ standard.
- The accelerometer and transmitter away from the pedal.
- Garmin Vector uninstalled.
- The transmitter plugs into the rear of the pedal spindle.
- Vector has a Look compatible cleat system but the body isn't an actual Look pedal.
- These are currently the only pedals available for the Vector system.
- The transmitter contacts the yellow piece on the inside of the spindle.
- Cleat tenstion can be adjusted with a hex wrench.
- Garmin Vector also uses external transmitters.
Garmin and Look/Polar are simultaneously launching an entirely new generation of power meter based in the pedal axle.
After years of rumors, development, cooperation between two companies and a merger by another, pedal-based power meters are finally (almost) ready. Polar and Look teamed up to create the Keo Power system and Garmin purchased tech start-up Metrigear to develop Vector, their own power meter. Both units are scheduled to be ready for sale in the spring of 2012. Garmin’s unit will be released in March and Look/Polar will have them ready in January.
There are a few potential benefits to the pedal-based format compared to the current hub- and crank-based power meters.
First, they can be swapped between bikes without changing a major component.
Second, they can measure power when riding different wheels. Hub-based power meters cannot.
Third, they provide the power split between the left and right legs.
Fourth, they can measure force produced by the rider that never makes it to the drivetrain.
But measuring power through the pedals introduces complications that crank and hub units do not have to overcome. Power meters measure the deflection of a component and its velocity to find the rider’s power. All flex in the hub and crank is created by power actually directed into the drivetrain. But the pedals are not only flexed when the rider pedals, but when the rider stands on the pedals. The pedal power meter systems must differential actual pedaling power from the forces created by the rider leaning on the pedal or bouncing on the pedals while riding over rough surfaces. The spindles measure force, but force is only part of the equation for rider power. The other component is velocity. To measure actual power rather than force on the pedals mistaken for power, both units use accelerometers in their external transmitters to measure pedal velocity (cadence, which means the rider is actually pedaling), and the transmitter pieces must be fixed almost exactly perpendicular to the crank arm to accurately measure power.
Details about Keo Power and Garmin Vector on pages two and three.Pages: 1 2 3