The Cassini 16 Test Head rotates to accommodate multiple docking scenarios including the most common, docking "Up" to a handler, "Right" or "Left" for turret or gravity feed handlers, or "Down" to dock to a prober. The Test Head also intentionally swivels in a 3-axis horizontal motion so that the Fixture docking process does not strain the blind mate connections between the Fixture and Test Head. The locking mechanism provides precise and fixed locking ability to secure the Test Head in any arbitrary rotation and tilt angles. The Test Head also allows for tuned adjustment to the swivel joint assembly used to reduce the total amount of swivel based on the target weight of the installed TIMs and Fixture. Watch "Using Cassini Head Rotation Lock (Preview)" Instructional Video below to see the Test Head rotation lock features in action.

New Features

1. Lock at arbitrary positions anywhere along the 280° of rotation, including Up 0°, Left -90°, Right +90°, and Down 180°. Left -90° is a new rotational position.
2. Rotation stops automatically at four safety zones to p revent an unbalanced Test Head from swinging dangerously.
3. Adjustable swivel arm that enables greater compensation for atypical loading.

Rotation and Safety Zones
The Test Head can rotate a total of 280° from the standard UP position at 0° to the new Left position at -90°. From the Up position at 0°, the Test Head can rotate to the Right position at +90° and the Down position at 180°. It is not possible to directly transition from Down position to Right position as shown as a red area in Figure 5.
There are four safety zones shown as orange areas in Figure 1 where the head will stop rotating when the lever is in the Unlocked region. Each zone corresponds to the four angles typically used when docking. The lock lever must be temporarily held in Release position while transitioning out of a safety zone. Once the Test Head is rotated beyond the edge of the safety zone, the handle should be returned to the Unlocked region while the Test Head is rotated until the desired angle is achieved.

IMPORTANT: The Test Head should be rotated with the TIMs installed. If attempting to rotate a Test Head with Fixture and/or docking hardware attached, install the appropriate counter weight; RIK0242A Test Head Single Counterweight (5 Kg or 14 pounds) or RIK0244A Test Head Double Counterweights (11 Kg or 25 pounds)..

CAUTION: Some Test Head rotational positions move the center of gravity so that rotating the Test Head requires force. For your safety, RI recommends having an assistant available to help until comfortable using the rotation lock.

Figure 1: Rotation (280 Degrees) and Four Safety Zones



Blue- Test Head can be locked in any of these positions (including orange safety zones).
Orange- When attempting to rotate out of a safety zone, the handle requires constant force to move the lever into Release position until the Test Head is rotated into the adjacent blue area. The handle should be let go when the Test Head rotates beyond the safety zone (blue area), until the Test Head is captured again within a safety zone.
Red- Unavailable. Test Head will not rotate between the 90 degree "Right"

Rotation Lock Lever Positions
The lever has a handle and can be moved into the Lock position, Unlocked region and Release position. The lever is adjusted by pushing or pulling on the handle in clockwise or counterclockwise direction. No force is needed when in Unlocked position indicated by the dashed line. Steady force on the handle is required to move into Lock or Release positions indicated by the arrows, until the final position is reached at either end. The Test Head will remain locked and the handle will stay in the "Lock" position until the lever is manually moved into the Unlocked region.

Release Position

The Release position is used to rotate the Test Head beyond the 5 degrees off center of the current safety zone. The lever should only be in this position while attempting to rotate the Test Head outside of the current 10 degree safety zone. The lever will return to Unlocked region when the handle is let go.

To Release: Rotate the lever by pulling the handle counterclockwise from Unlock position and rotating the Test Head out of the safety zone. If it does not release, rotate the Test Head a few degrees in the opposite direction before rotating in the desired direction. The handle should be let go while once exiting the safety zone until the next safety zone is encountered. Let go of the handle to return the lever to Unlocked position.

Unlocked Region

The Unlocked position is used to position the Test Head to the desired rotation and tilt angle. The lever should only be in this region while adjusting the angle and should transition to Release position to rotate outside of the current safety zone or to Lock position to secure the Test Head.

To Use The Unlocked Region: Rotate the lever by pulling the handle counterclockwise from Lock position until the handle stops resisting or releasing the handle from Release position. The handle can freely move approximately 30 degrees between the starting edge of the Lock position and the starting edge of the Release position as indicated by the dashed lines. Let go of the handle to leave the lever in Unlocked position.

Lock Position

The lock position holds the tilt and rotation of the Test Head into any available angle. The lever should remain in this position when docking, using the Diag/Cal Interface plate, or moving the infrastructure. Adjust the tilt to approximate level before locking. Use the Level feature of the Measure App on the RI eManual (iPad mini) to position the Test Head while locking.

To Lock: Rotate the lever by pushing the handle clockwise, applying force through the Lock region until the handle stops in the Lock position. Let go of the handle to leave the lever in Lock position.

Tilt Compensation Tuning

Tilt compensation can be adjusted to set the total degrees available for tilting the Test Head forward and back. When additional weight is added, the Test Head may wilt under the additional load so it becomes difficult to reach the target 0°. The tilt adjust screw can be loosened or tightened to compensate, so the Test Head is close to 0° when fully loaded with Fixture and docking equipment. Tuning is intended to be performed by an authorized Roos Instruments agent because it requires the head access panel to be removed. Please contact [email protected] to schedule an adjustment.


Video 1: "Using Cassini Test Head Rotation Lock (Preview)" Instructional Video @ https://youtu.be/ajDIIV9Oc-E