Topcon AP-L1A - Setting Tracking Parameter; Setting of Tracking Detecting Sensitivity; Setting Tracking Speed

7. APPLICATION FUNCTIONS
7-7
7.3 Setting Tracking Parameter
A proper setting for each parameter such as, travel speed of prism, layout of prisms at job site,
minimum tracking distance, and required measuring accuracy are necessary for custom use.
See how to set to "15.1.1 TRK-SET : Setting for Tracking Functions" for each items.
7.3.1 Setting Tracking Speed
The tracking accuracy (aiming accuracy) shall be determined in the best condition by the
relationship of moving speed of the prism and the distance between AP-L1A and the prism at the
field. Since the tracking speed represents the rotating speed of AP-L1A, if the prism’s traveling
speed is high, yet the distance of the prism is far from the AP-L1A, the tracking speed can be low.
Each setting (Low/Medium/High) has each characteristic, typically tracking accuracy (aiming
accuracy). See Chapter 22 "Specifications".
Although High speed setting is suitable for tracking prism which is moving in higher speed, Medium
speed setting does not have significant disadvantage in tracking ability except the mentioned
tracking accuracy.
Typical situation that each setting is recommended for are as in followings.
LOW
(Low speed)
 In case requiring auto aiming in high accuracy to the prism which is still or
almost still.
 Required measuring accuracy in still condition but not tracking
performance during traveling prism.
 Suitable for fixed point observation, management of landslides, surveying
displacement of dam or bridge and control work for sealed machine.
MEDIUM
(Medium speed)
 This setting mode is in good balance both for tracking performance of
traveling objects and sighting accuracy in still condition.
 Suitable for one person surveying or stake out work.
 Used when accuracy is as important as continuous relative position data
of the prism which is traveling in high speed.
HIGH
(High speed)
 Measuring accuracy is prior to high speed tracking than low.
 Suitable for controlling of construction machinery in high speed or real
time surveying of variety traveling objects.
7.3.2 Setting of Tracking Detecting Sensitivity
In the case of relatively near distance surveying, setting in low or medium sensitivity is effective to
avoid measuring error come from extra reflectors except prism such as cars or motorcycles. In the
same time you have to know when you set in low or medium, the tracking possible distance also
will be short. Normal setting is in high sensitivity.
Tracking p ossible distance (in normal atmospheric condition)
Prism type 2 1p Pin-pole prism 1p
HIGH 1,000m (3,300ft) 700m (2,300ft)
MEDIUM about 400m (1,300ft) about 400m (1,300ft)
LOW about 200m (650ft) about 200m (650ft)
Sensitivity