Week 24 (Mar. 27, 2019): Revised Gimbal Motor Velocity Calculations

-

Today, we realized our velocity calculation was incorrect because we used the wrong radius in the circumference calculation; we erroneously used the diameter (35 mm) as the radius.





Source: Carryer, J.E, et. al. (2012) Introduction to Mechatronic Design. Pps. 536-541, 547-548.


We were expecting a velocity of around 1.0 m/s, but 0.88 m/s is good enough, with the new bogie, the new gimbal motor, the new 12V power supply from the boost converter, and a 2:1 gearing set.

Comments

Post a Comment

Popular posts from this blog

Week 29 (May 1, 2019): CAD of Induction Charger Hub & Podcar Door, then 3D Printing

-
Image
This week, while David worked on the Raspberry Pi and the Arduino code, Patrick completed the CAD (computer-aided-design) models. We had to create 3D solid modeling of two parts: the induction charging hub to hold the induction transmitter coil and the pod car door to hold the induction receiver coil. Over the weeks, the CAD models underwent several revisions. The induction hub saw two revisions, with the third design being the final version. Because the 3D printer available to us in the shop, the Prusa Mark3 i2, had a bed length of 10 inches, we had to restrict the length of the charging hub to a safe 9.5 inches. Version 1 simply entailed us placing the hub on the side of the bracket and then screwing it into place on the bracket’s side via the two holes at the top: For version 2, in addition to placing the hub on the side of the bracket and then screwing it into place on the bracket’s side via the two holes at the top, the bracket would wrap around the two bracke...
Read more

Week 28 (Apr. 24, 2019): Final motor selection – Mini-Stepper Motor

-
Image
Since last week, we have been trying to run the new brushless DC motor; however, it is still difficult to control, let alone its speed. Therefore, we had to pursue our alternative motor, the mini-stepper motor that runs at 5V. Found in Arduino starter kits, this mini-stepper motor is accompanied by its dedicated motor driver board, the ULN2003, which is a chip containing a series of Darlington pair transistors. An image of the stepper motor and the ULN2003 board is shown below:   Sources: https://www.adafruit.com/product/858 https://www.amazon.com/gp/product/B01CP18J4A/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1   We were able to successfully run the new mini-stepper motor with the sample code included with the Arduino starter kit. One benefit to using the sample code is that it utilizes the Stepper library’s functions. One use function is the setSpeed( ) function, which allows the user to set the RPM speed of the stepper motor. We found that the ma...
Read more