Chip-cn-dat/xysemi-dat/xysemi-dat.md
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## XR2981
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+
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+FEATURES
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+
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+- 2.7V to 5.5V input voltage Range
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+- Efficiency up to 96%
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+- 24V Boost converter with 12A switch current Limit
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+- 600KHz fixed Switching Frequency
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+- Integrated soft-start
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+- Thermal Shutdown
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+- Under voltage Lockout
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+- Support external LDO auxiliary power supply
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+- 8-Pin SOP-PP Package
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+
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+
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+
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+
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https://cdn.hackaday.io/files/1829407826904960/Xysemi_XR2981.pdf
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3.3V~5V Input 24W Output Step-up DC/DC Converter
Tech-dat/robotic-dat/Quadruped-Locomotion-dat/2026-03-08-01-03-47.png
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Tech-dat/robotic-dat/Quadruped-Locomotion-dat/Quadruped-Locomotion-dat.md
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+
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+# Quadruped-Locomotion-dat
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+
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+
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+Direct-Drive Servos
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+
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+When your servo horns are the feet, the most efficient movement is a **coordinated rotation** that mimics a wheel but maintains the balance of a quadruped.
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+
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+### 1. The Diagonal Trot (Recommended)
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+This is the smoothest and fastest way to move. You move diagonal pairs in a "circular" or "elliptical" path.
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+
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+* **Group 1:** Front Left (FL) and Rear Right (RR)
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+* **Group 2:** Front Right (FR) and Rear Left (RL)
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+
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+**The Logic:**
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+
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+1. **Group 1** rotates "down and back" (pushing the floor) while **Group 2** rotates "up and forward" (lifting through the air).
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+2. The pairs switch roles.
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+3. By using a 180° phase shift between the two groups, the robot's body stays level while moving forward.
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+
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+
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+
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+---
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+
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+### 2. The "Crawl" (High Stability)
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+
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+If your robot is top-heavy or the servo horns are very long, a Trot might be too shaky. Use a **Sequence Walk** instead.
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+
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+* **Sequence:** FL -> RR -> FR -> RL
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+* **Action:** Only one "foot" moves forward at a time while the other three stay on the ground.
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+* **Benefit:** The Center of Mass (CoM) is always supported by a triangle of legs, making it nearly impossible to tip over.
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+
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+---
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+
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+3. Mechanical Implementation Tips
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+
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+
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+| Foot Design | Benefit | Best For |
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+| :--- | :--- | :--- |
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+| **Offset "L" Shape** | Increases the "stride" length without needing a larger servo rotation. | Speed |
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+| **Circular/C-Shape** | Provides a smooth "rolling" contact point with the floor. | Stability/Grass |
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+| **Rubber-Tipped Point** | Increases friction to prevent the servos from slipping during the "push" phase. | Hard floors |
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+
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+
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+
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+1. Simple Code Logic (Pseudocode)
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+To implement the **Trot**, your code should look something like this:
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+
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+```cpp
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+// Phase 1
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+Servo_FL.write(45); // Push
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+Servo_RR.write(45); // Push
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+Servo_FR.write(135); // Lift/Reset
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+Servo_RL.write(135); // Lift/Reset
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+
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+delay(200);
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+
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+// Phase 2
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+Servo_FL.write(135); // Lift/Reset
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+Servo_RR.write(135); // Lift/Reset
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+Servo_FR.write(45); // Push
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+Servo_RL.write(45); // Push
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+
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+
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+```
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+
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+
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+### Crank-Rocker
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+
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+![](2026-03-08-01-05-45.png)
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+
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+
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+### Klann Linkage
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+
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+![](2026-03-08-01-03-47.png)
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+
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+### Diagonal Trot
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+![](2026-03-08-01-07-55.png)
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+
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+### trot gait
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+The **Trot Gait** is a symmetrical, "two-beat" gait used by four-legged animals and robots. Its defining characteristic is the **simultaneous movement of diagonal pairs of legs**.
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+
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+### 1. The Trot Gait Mechanics
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+In a trot, the legs move in the following sequence:
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+* **Pair A:** Front Left (FL) and Rear Right (RR) move together.
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+* **Pair B:** Front Right (FR) and Rear Left (RL) move together.
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+
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+* **Symmetry:** The movement of the left side is a mirror image of the right side, shifted in time.
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+* **Duty Factor:** In a standard trot, each foot is on the ground for about 50% of the stride cycle.
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+* **Efficiency:** It is highly energy-efficient for traveling at medium speeds because it maintains a stable "support line" between the diagonal feet.
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+
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+---
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+
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+### 2. Comparison of Common Quadruped Gaits
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+Beyond the trot, quadrupeds use several other gait patterns depending on the required speed and terrain stability.
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+#### A. The Walk (Static Stability)
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+* **Pattern:** Each leg moves individually (e.g., RL -> FL -> RR -> FR).
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+* **Stability:** At least three legs are on the ground at all times, keeping the Center of Mass (CoM) within the support triangle.
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+* **Usage:** Best for very slow, precise movement over uneven terrain.
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+
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+#### B. The Pace (Lateral Gait)
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+* **Pattern:** Both legs on the **same side** move together (e.g., FL + RL, then FR + RR).
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+* **Characteristics:** This creates a side-to-side swaying motion. It is common in camels and some breeds of horses.
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+* **Robot Note:** Harder to balance in robotics due to the large lateral weight shift.
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+
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+#### C. The Bound (Pitching Gait)
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+* **Pattern:** Both front legs move together, followed by both rear legs.
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+* **Characteristics:** High-speed leaping motion. It involves significant "pitch" (tilting up and down) of the body.
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+* **Usage:** Used by squirrels and dogs for rapid acceleration or clearing obstacles.
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+
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+#### D. The Gallop (Asymmetrical High Speed)
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+* **Pattern:** A four-beat sequence with a "flight phase" where all four feet are off the ground.
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+* **Characteristics:** The fastest possible gait. It utilizes the elasticity of the spine to increase stride length.
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+
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+#### E. The Pronk (High Impact)
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+* **Pattern:** All four legs jump and land simultaneously.
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+* **Usage:** Often seen in springboks or gazelles. In robotics, it's used to test motor peak power and landing impact absorption.
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+
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+---
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+
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+### 3. Summary Table
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+| Gait Name | Pairing Type | Beats | Best For |
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+| :--------- | :------------------ | :---- | :------------------------------------- |
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+| **Walk** | Single Leg | 4 | Maximum Stability |
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+| **Trot** | **Diagonal Pairs** | **2** | **Efficiency / Medium Speed** |
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+| **Pace** | Lateral Pairs | 2 | Long-distance travel (certain species) |
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+| **Bound** | Front/Rear Pairs | 2 | Clearing Obstacles / Rapid Burst |
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+| **Gallop** | No Pairs (Sequence) | 4 | Maximum Speed |
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Tech-dat/robotic-dat/robotic-dat.md
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- [[robotic-dat]] - [[robotic-joint-dat]]
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+- [[Quadruped-Locomotion-dat]]
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+
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+
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## Electronics
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- [[vision-dat]]
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+
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+
battery-dat/battery-supply-dat/battery-supply-dat.md
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- [[JW3651-dat]]
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+## boost
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+boost from 2.7V - [[DCDC-boost-dat]]
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+
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+
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+
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+
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+## LDO
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+
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+- lowest [[LDO-dat]] drop from 3.35V
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power-dat/DCDC-dat/dcdc-boost-dat/dcdc-boost-dat.md
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10A 150W == [[OPM1013-dat]]
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-
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+- [[battery-dat]]
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