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Get FREE copies of Circuit Cellar magazine’s November issue and Elektor magazine’s November issue with your order, while supplies last. To get your free issues, enter the coupon codes CIRCUIT1114 and ELEKTOR1114 into your shopping cart. Each magazine will add 6 ounces to the package weight when calculating your shipping options.
Introducing Robot Magazine
We are now also offering free issues of Robot, a bimonthly magazine specifically for the robot enthusiast! We have the three most recent issues available, while supplies last:
To get your free issues, enter the coupon codes ROBOT0714, ROBOT0914, and ROBOT1114 for July/August, September/October, and November/December, respectively. Each magazine will add 6 ounces to the package weight when calculating your shipping options.
For more information, see our free Robot Magazine offers category.
Several gear ratios of our medium-power (MP) micro metal gearmotors are now available with extended motor shafts:
- 10:1 MP micro metal gearmotor with extended motor shaft – 2200 RPM (no-load) and 3 oz-in torque (stall) at 6 V
- 75:1 MP micro metal gearmotor with extended motor shaft – 290 RPM (no-load) and 17 oz-in torque (stall) at 6 V
- 100:1 MP micro metal gearmotor with extended motor shaft – 220 RPM (no-load) and 19 oz-in torque (stall) at 6 V
The extended motor shaft rotates at the same speed as the input to the gearbox and offers a way to add an encoder, such as our new magnetic encoder for micro metal gearmotors (pictured below), to provide motor speed or position feedback.
Our family of Mini Plastic Gearmotors is growing! We have added HP versions with more powerful motors for increased torque and speed, and we are now carrying versions with extended motor shafts intended for use with custom encoders for motor speed and position feedback. (These extended-shaft versions are not compatible with the magnetic encoders we just released for our Micro Metal Gearmotors; we will have a similar encoder solution for these plastic gearmotors at some point, but for now we are offering them for people who want to make their own encoders.) The following table shows the current state of our Mini Plastic Gearmotor family:
@ 4.5 V
@ 4.5 V
@ 4.5 V
90° output + motor shaft
offset output + motor shaft
|1250 mA||150 RPM||25 oz-in||120:1 mini HP||120:1 mini HP||120:1 mini HP||120:1 mini HP|
|low-power||800 mA||120 RPM||20 oz-in||120:1 mini||120:1 mini||120:1 mini||120:1 mini|
|80 RPM||30 oz-in||180:1 mini||180:1 mini|
We are particularly excited about these gearmotors because they offer a great combination of performance and affordability; don’t be surprised if you find these motors in some of our future robots and robot kits! For more information about all of these gearmotors, see our Mini Plastic Gearmotors category.
Last month, we introduced our new carriers with Sharp GP2Y0A60SZLF analog distance sensors, a part we are very excited about and have been trying to get for the past five years. Those complete sensor modules ship with the GP2Y0A60SZLF installed on our compact carrier board, which includes all of the required external components and provides a more convenient interface to the sensor (and a mounting hole!). Well, we are now offering the carrier boards without the sensor for those who already have Sharp GP2Y0A60SZLF units and are looking for an easy way to incorporate them into their projects. The carrier boards are available in two configurations: a 5V version for operation from 2.7 V to 5.5 V and a 3V version for operation from 2.7 V to 3.6 V:
For more information, see the product pages.
Get FREE copies of Circuit Cellar magazine’s October issue and Elektor magazine’s October issue with your order, while supplies last. To get your free issues, enter the coupon codes CIRCUIT1014 and ELEKTOR1014 into your shopping cart. Each magazine will add 6 ounces to the package weight when calculating your shipping options.
Remember the post I wrote two weeks ago about our tiny D24V25F5 voltage regulator and some of the testing that we did on it? Well, we were so happy with how that regulator turned out that we decided to make a higher-power version with a larger inductor and beefier MOSFETs. This new regulator is the D24V50F5, and while it is only 0.1″ bigger than its 2.5 A cousin, it can deliver 5 amps!
|Side-by-side comparison of the 2.5A D24V25Fx (left) and 5A D24V50Fx (right) step-down voltage regulators.|
You can see the bigger MOSFETs on the bottom side:
|Comparison of the D24V25Fx (left) and D24V50Fx voltage regulators showing larger MOSFETs on the higher-power board.|
The D24V50F5 can also take inputs up to 38V and has typical efficiencies of 85% to 95%. It’s amazing how much power these little 3×3 mm MOSFETs can handle, and with its compact size and high power, this regulator is our new favorite.
Everyone wants encoders on their motors. If you think you don’t, you just don’t know it yet. I think the main reason is that we really just want motors to do what we tell them to do, but they don’t. One of the most common beginner questions we get is some variation of, “why doesn’t my robot go straight?” or “I got two of the same motor but they do not go the same speed; is something wrong with one of them?” More seasoned robot builders know that since there will always be variations in everything that contributes to a motor’s performance, our best hope is to put a sensor on the motor to monitor what is actually happening and then adjust the motor control to make reality better match our desires. Continued…
Get FREE copies of Circuit Cellar magazine’s September issue and Elektor magazine’s September issue with your order, while supplies last. To get your free issues, enter the coupon codes CIRCUIT0914 and ELEKTOR0914 into your shopping cart. The Circuit Cellar magazine will add 6 ounces and the Elektor magazine will add 7 ounces to the package weight when calculating your shipping options.
We recently substantially reduced prices on our stepper motor driver carriers, and I figured this announcement was a good time to give you an update on our perspective and capabilities.
It has been over five years since I designed our original stepper motor driver carrier, which was for the A4983 from Allegro. While fairly straightforward, the implementation reflected several design philosophies that go into Pololu products, such as making the boards as small as practical and including the right extra components to make the main chip easily usable without unnecessarily limiting its features. Continued…