Clever Gear and Racks Modeling and Animation SimulationThe following are some methods for modeling and animation of gears and racks:
** 1. Modeling **
1. ** Gear modeling in UP software (manual modeling steps)**
- First of all, one had to understand the meaning of gear parameters, such as module (m), pressure angle (a, the general standard is 20 degrees), number of teeth (Z), pitch circle diameter (D), etc. The module, pressure angle, and number of teeth were the three basic parameters of the gear. There was a relationship between them (such as module = number of teeth/pitch circle diameter), as well as parameters such as tooth height, tooth thickness, and tooth pitch (tooth top height = 1* module, tooth root height = 1.25* module, tooth pitch = Pi * module).
- In the UP software, press the button of <<ctrl-e>> to open the expression. Enter the relevant expression parameters (for example, generate it according to the default gear parameters of the GC toolbox, for example, m = 20, z = 20), and insert the regular curve to generate the evolutions.
- He inserted the sketch and drew the tooth top circle, pitch circle, root circle, and base circle of the gear. He used a straight line to connect the intersection point of the evolute and the pitch circle at the origin coordinates, and made an auxiliary straight line to form an angle with it (the angle value was 90 degrees divided by the number of teeth). Then, he used the auxiliary line to mirror the evolute.
- A small circle was created at the origin coordinates, and the tangents from the intersection of the evolves and the base circle to the small circle were made. These areas were used to stretch into a gear, and after rounding the spur and cylindrical surface (0.38*m size), the array surface was used to array, thus completing the cylindrical gear modeling.
2. ** Gear rack modeling in the UG software **
- It could be generated using a plug-in or manually modeled. During manual modeling, an isosceles-shaped rhomboid was created on top of a rectangular shape. The size was constrained according to the rack parameters, and then the array was stretched. The number of arrays was the number of teeth, and the pitch was the pitch (Pi *m). Since the rack and the gear had a working range, there was no need to round the bottom.
3. ** Gear and rack modeling in Solid Works (steps not mentioned in detail, but ideas can be inferred)**
- It should also be based on the basic parameters of the gear rack, such as the module and the number of teeth. For gears, to construct the shape of the teeth, it might involve drawing curves such as an evolute, and for racks, it was necessary to construct a straight tooth shape that matched the gear.
4. ** A general idea for modeling gears and racks (Take creating a gear, then creating a rack in the tooth slot and expanding it as an example)**
- First, a gear was created, and then a single tooth pattern of the rack was created in a gear slot. Then, it was expanded in the corresponding direction to complete the creation of the rack.
5. ** Modeling based on parameters **
- No matter what kind of software it was, it had to be based on the basic parameters of the gear rack. For example, the module determined the size of the teeth, and the number of teeth affected the overall size of the gear and the relationship with the rack. The pressure angle also affected the shape and force of the tooth.
6. ** Points to note in modeling **
- There must be a gap between the gear and the rack, and it must not be too tight. The rack could be regarded as a cylindrical gear with an infinite diameter. This characteristic had to be taken into account when modeling to ensure the correct relationship between the rack and the gear.
** 2. Animation simulation **
1. ** Animation simulation in the UG software **
- After the modeling of the gear and rack was completed, the assembly constraint engagement was carried out. It was only necessary to make contact between the reference circle of the gear and the rack, and there was a contact between the gear and the surface of the rack. After the fitting was completed, he entered the motion simulation module and created a new motion simulation.
- According to the motion simulation trilogy, the parts to be moved were set as connecting rods (the 1847 version was a moving body), and the motion of the gear bar was sliding. A sliding pair was added.
2. ** Animation simulation in Solid Works (steps not mentioned in detail, but the idea can be inferred)**
- First, he would assemble the gears and racks to match them correctly. Then, in the animation module, he would set the rotation motion of the gears or the straight line motion of the racks. He would also set the speed, direction, and other parameters of the motion. He could also add driving force (such as the motor to the driving mechanism). Finally, he would generate and preview the animation.
3. ** Key points in animation simulation **
- It was necessary to correctly set the motion relationship between the gear and the rack to ensure that the mesh transmission of the two complied with the actual physical laws. When adding constraints and driving forces, one had to consider the actual application scenarios, such as the motion requirements of the gear rack used to move the machine slide in the machine tool.
<a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>