Assembly motion study basics in Solidworks - Real Business Scenario

Scenario Mode

👤 Your Role: You are a mechanical engineer working on a new product design.

📋 Request: Your manager wants you to analyze how the parts in an assembly move together to ensure smooth operation.

📊 Data: You have a SolidWorks assembly file with multiple parts connected by joints and mates.

🎯 Deliverable: Create a motion study report showing the movement of parts over time, highlighting any collisions or interferences.

Sample Data

Part Name	Joint Type	Degrees of Freedom	Initial Position	Motion Input
Gear A	Revolute	1 (Rotation)	0 degrees	Rotate 360 degrees in 10 seconds
Gear B	Revolute	1 (Rotation)	0 degrees	Driven by Gear A
Slider	Prismatic	1 (Linear)	0 mm	Slide 50 mm forward in 5 seconds
Arm	Revolute	1 (Rotation)	0 degrees	Rotate 90 degrees in 5 seconds

1

Step 1: Open the assembly file in SolidWorks and check all mates and joints for correct setup.

Verify that Gear A and Gear B are connected with a gear mate, Slider has a prismatic mate, and Arm has a revolute mate.

Expected Result

All parts have correct mates allowing intended motion.

2

Step 2: Create a new motion study in SolidWorks.

Select 'Motion Study' tab, click 'New Motion Study'.

Expected Result

A blank motion study timeline appears.

3

Step 3: Add motor to Gear A to rotate 360 degrees over 10 seconds.

Insert Motor: Select Gear A, set rotation speed to 36 degrees per second for 10 seconds.

Expected Result

Gear A rotates fully once in 10 seconds.

4

Step 4: Set Slider to move linearly 50 mm forward in 5 seconds.

Add linear motor or displacement: Select Slider, set linear motion 50 mm over 5 seconds.

Expected Result

Slider moves forward 50 mm smoothly in 5 seconds.

5

Step 5: Set Arm to rotate 90 degrees in 5 seconds.

Add motor: Select Arm, set rotation speed 18 degrees per second for 5 seconds.

Expected Result

Arm rotates 90 degrees smoothly in 5 seconds.

6

Step 6: Run the motion study simulation.

Click 'Calculate' or 'Play' to simulate motion over timeline.

Expected Result

Animation shows parts moving as configured.

7

Step 7: Check for collisions or interferences during motion.

Enable collision detection in motion study options and observe results.

Expected Result

No collisions detected or identify where collisions occur.

8

Step 8: Generate a motion study report with key findings and screenshots.

Use SolidWorks report tool to export motion study summary and images.

Expected Result

Report shows motion timeline, part movements, and collision analysis.

Final Result

Motion Study Report
-------------------
Time (s) | Gear A (deg) | Gear B (deg) | Slider (mm) | Arm (deg)
-------------------------------------------------------------
0        | 0            | 0            | 0           | 0
5        | 180          | 180          | 50          | 90
10       | 360          | 360          | 50          | 90

No collisions detected during motion.

✓Gear A and Gear B rotate synchronously as expected.

✓Slider moves forward smoothly within 5 seconds.

✓Arm completes 90-degree rotation without interference.

✓No collisions or interferences detected in the assembly motion.

Bonus Challenge

Add a spring force to the Slider to simulate return motion after sliding forward.

Show Hint

Use SolidWorks motion study 'Force' feature to apply a spring force with defined stiffness and preload.

Practice

1. What is the main purpose of an assembly motion study in SolidWorks?

easy

A. To visualize how parts move together in an assembly

B. To create 3D models from 2D sketches

C. To generate technical drawings automatically

D. To calculate the weight of individual parts

Solution

1. Step 1: Understand the function of motion study

   Assembly motion study is used to see how parts move and interact in an assembly.

2. Step 2: Compare options with this function

   Only To visualize how parts move together in an assembly describes visualizing part movement, which matches the purpose.

3. Final Answer:

   To visualize how parts move together in an assembly -> Option A

4. Quick Check:

   Assembly motion study = visualize part movement [OK]

Hint: Think: motion study means showing movement [OK]

Common Mistakes:

• Confusing motion study with drawing creation
• Thinking it calculates weight or mass
• Assuming it creates 3D models from sketches

2. Which of the following is the correct first step to create a motion study in SolidWorks?

easy

A. Open the Motion Study tab at the bottom of the assembly window

B. Export the assembly as a STEP file

C. Create a new part file

D. Run a simulation analysis from the Simulation tab

Solution

1. Step 1: Identify how to start a motion study

   Motion studies are started by selecting the Motion Study tab in the assembly interface.

2. Step 2: Eliminate unrelated options

   Exporting files, creating parts, or running simulation analysis are not the first step for motion studies.

3. Final Answer:

   Open the Motion Study tab at the bottom of the assembly window -> Option A

4. Quick Check:

   Start motion study = open Motion Study tab [OK]

Hint: Look for the Motion Study tab in the assembly window [OK]

Common Mistakes:

• Trying to export files before starting motion study
• Confusing motion study with simulation analysis
• Starting with a new part instead of assembly

3. Given this simple motion study setup: a gear rotates 90 degrees over 5 seconds. What is the angular velocity in degrees per second?

medium

A. 450 degrees per second

B. 90 degrees per second

C. 18 degrees per second

D. 0.18 degrees per second

Solution

1. Step 1: Identify total rotation and time

   The gear rotates 90 degrees in 5 seconds.

2. Step 2: Calculate angular velocity

   Angular velocity = total rotation / time = 90 / 5 = 18 degrees per second.

3. Final Answer:

   18 degrees per second -> Option C

4. Quick Check:

   90° ÷ 5s = 18°/s [OK]

Hint: Divide total degrees by total seconds for velocity [OK]

Common Mistakes:

• Multiplying instead of dividing degrees by time
• Confusing degrees with radians
• Ignoring the time duration

4. You created a motion study but the parts do not move as expected. Which of these is the most likely cause?

medium

A. The computer does not have enough RAM

B. The assembly file is saved in the wrong folder

C. The parts are missing color textures

D. The mates between parts are not properly defined

Solution

1. Step 1: Identify what controls part movement

   Part movement depends on mates that define how parts connect and move relative to each other.

2. Step 2: Evaluate other options

   File location, colors, or RAM do not directly affect motion study movement.

3. Final Answer:

   The mates between parts are not properly defined -> Option D

4. Quick Check:

   Movement depends on mates = correct mates needed [OK]

Hint: Check mates first if parts don't move [OK]

Common Mistakes:

• Blaming file location for motion issues
• Thinking textures affect movement
• Assuming hardware issues cause no movement

5. You want to simulate a door opening in an assembly. Which combination of steps will best create a realistic motion study?

hard

A. Use the explode tool to separate the door from the frame

B. Add a hinge mate, set rotation limits, and apply a motor to rotate the door

C. Create a new part for the door, then run a stress analysis

D. Add a fixed mate, color the door, and export as animation

Solution

1. Step 1: Define realistic movement with mates

   A hinge mate allows rotation like a real door hinge.

2. Step 2: Control motion and automate it

   Rotation limits prevent unrealistic movement; a motor applies controlled rotation.

3. Step 3: Eliminate incorrect options

   Fixed mates prevent movement; coloring or exploding parts do not simulate motion realistically.

4. Final Answer:

   Add a hinge mate, set rotation limits, and apply a motor to rotate the door -> Option B

5. Quick Check:

   Hinge + limits + motor = realistic door motion [OK]

Hint: Use hinge mate plus motor for rotating parts [OK]

Common Mistakes:

• Using fixed mates that block movement
• Confusing explode tool with motion simulation
• Skipping rotation limits causing unrealistic motion