Unit 3: Hydraulic Arm Robots

The Principles of Fluid Power: Understand Pascal’s Law, which states that pressure exerted anywhere in a confined, incompressible fluid is transmitted equally in all directions.

Hydraulics vs. Pneumatics: Distinguish between systems using liquid (incompressible) and those using gas (compressible), and why hydraulics are chosen for heavy lifting.

Mechanical Advantage: Understand how the ratio of the surface area of the "master" cylinder (input) to the "slave" cylinder (output) affects force and distance.

Degrees of Freedom (DoF): Identify the four axes of motion on the T-Bot (base rotation, shoulder, elbow, and gripper) and how they define a robot’s work envelope.

System Components: Define the roles of the reservoir, transmission lines (tubing), and actuators (syringes) within a closed-loop system.

System Assembly: Construct the mechanical frame and integrate the hydraulic delivery system (tubing and syringes) following engineering schematics.

Fluid Management: "Bleed" the lines to remove air bubbles, ensuring the system is truly hydraulic and responsive rather than "spongy" (pneumatic).

Coordinate Motion: Operate four manual controllers simultaneously to move the arm’s end-effector to a specific coordinate in 3D space.

Troubleshooting: Identify and repair mechanical failures, such as friction in the joints, leaks in the tubing, or air infiltration in the cylinders.

Data Collection: Measure the input distance of the master syringe versus the output distance of the arm to calculate mechanical advantage.

• The "Pick-and-Place" Practical: Students must successfully move a small object (like a wooden block) from a starting position to a target elevated platform within a set time limit.

• Hydraulic Lab Report: Students complete a technical document where they:

  1. Label a diagram of the T-Bot’s mechanical system.

  2. Explain the effect of air bubbles on the arm's precision using the terms compressibility and force.

  3. Calculate the Work Envelope by tracing the maximum reach of the arm on a piece of grid paper.