Pololu Wheel 42x19mm Pair
This custom-designed white plastic wheel has a rubber tire measuring 1.65" (42 mm) in diameter and is designed to fit the output shafts on our micro and mini metal gearmotors as well as the Solarbotics metal gear motors. Teeth on the hub optionally allow a reflectance sensor to be used for encoder feedback. These wheels are sold in pairs.
Overview
This rugged wheel is designed to fit securely on the output shafts of our micro and mini metal gearmotors. These gearmotors should be mounted onto the side of the hub with the protruding teeth, as shown on the right. The output shaft will slide into the socket easily at first but will achieve a snug fit when pressed through to the other edge of the hub.
The output shafts on the Solarbotics metal gear motors will also fit these wheels, but because they are shorter they will have to be mounted onto the other side of the wheel where the fit is tighter (which means the Solarbotics metal gearmotors will not work with the quadrature encoder associated with this wheel). These wheels will also work in this orientation on the Pololu 120:1 mini plastic gearmotor 90-degree 3mm D-shaft output.
Our extended micro metal gearmotor bracket is specifically designed to work with this wheel. Please note that the non-extended version of our mounting bracket (product #989) will not work well with this wheel.
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| Micro metal gearmotor with Pololu wheel 42×19mm and extended bracket. |
Specifications
- Diameter: 1.65" (42 mm)
- Width of tire: 0.75" (19 mm)
- Weight: 0.66 oz (19 g)
Encoder Feedback
The hub has twelve teeth, each 3 mm wide and separated from its neighbors by 3 mm gaps. We offer a quadrature encoder that uses these teeth to provide up to 48 counts per revolution (a linear resolution of just under 3 mm or 1/8"). The encoder is designed to work with our extended micro metal gearmotor bracket and our micro metal gearmotors as shown in the pictures below. The compact layout of the board fits all of the components within the envelope of the hub and tire, allowing the board to be mounted between the motor and a chassis. The encoder can be purchased as an individual unit or as a part of an encoder set that includes two encoders, a pair of extended brackets, and a pair of 42×19mm wheels.
The following oscilloscope capture shows the two encoder output channels while the 42×19mm wheel is spinning at close to 630 RPM. The two channels are approximately 90° out of phase, allowing you to determine both rotational speed and direction.
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| Oscilloscope capture of encoder outputs with the wheel spinning at 630 RPM. |
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Dimensions
| Size: |
42 x 19 mm |
| Weight: |
0.56 oz1 |
| Shaft diameter: |
3 mm2 |
General specifications
Notes:
- 1
- Per wheel, including tire.
- 2
- D-shaped hole for press fit onto Pololu micro and mini metal gearmotors.
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Dimensions of the Pololu wheel 42×19mm hub/Pololu track set drive sprocket. |
Pololu 5" round robot chassis RRC04A with drive components and encoders mounted on top. |
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Pololu wheel 42×19mm, interior view. |
Pololu wheel 42×19mm with micro metal gearmotor. |
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Pololu wheel 42×19mm with micro metal gearmotor. |
Micro metal gearmotor and Pololu wheel 42×19mm mounted with extended mounting bracket. |
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Micro metal gearmotor with Pololu wheel 42×19mm and extended bracket. |
Encoder for Pololu wheel 42×19mm with wheel, motor, and bracket. |
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Encoder for Pololu wheel 42×19mm with wheel, motor, and bracket. |
Encoder for Pololu wheel 42×19mm with motor, bracket, and hub. |
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Oscilloscope capture of encoder outputs with the wheel spinning at 630 RPM
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FAQs
What are the Pololu wheels made of?
- The material used to make the hubs of Pololu wheels is ABS (also known as Polylac) PA-747.
- The material used to make the tires of Pololu Wheel 42×19mm is natural rubber.
- The material used to make the tires of all Pololu wheels except the Pololu Wheel 42×19mm is Silicone.
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No recommended products at the moment.
