Kaldor android
The society in and around Kaldor City was apparently almost wholly dependent on humanoid robots for servants and manual labour. The sandminers, which made a major contribution to Kaldor's economy, were almost entirely crewed by robots of this type. Although superficially similar (all were designed to be aesthetically pleasing), the robots were constructed in several varieties which differed in their intelligence, autonomy, and ability to communicate.
History
The robots had become fundamental to Kaldorian society by the time of the Fourth Doctor's first visit there. The society itself was threatened when a disguised Taren Capel began to reprogram the robots on one sandminer to murder the human crew — civilisation would collapse if the citizens lost their faith in the robot workforce. The Doctor subtly altered Capel's voice pattern, and, not recognising him, his own robot followers turned on him and killed him. All the modified robots were destroyed shortly afterwards. (TV: The Robots of Death)
The murders on Storm Mine 4 were covered up and plans were made to introduce a new, more humanoid robot. However, the prototype SASV-1 believed it was Taren Capel and reprogrammed robots as killers. SASV-1 was destroyed by the Doctor and the new class of robots were abandoned. (PROSE: Corpse Marker)
As was eventually discovered, Capel's plan also had a second phase that was activated after his death. It concerned the transmission of a specially designed program to modify the robots' basic operational software in order to turn them into murderers. (AUDIO: Taren Capel)
The practice of putting a human crew on a sandminer was discontinued. Attempts were still made to improve robot design, such as the Ultra-Voc prototype robot. However, on its first assignment the UV disappeared. It had realised its status as a slave and rebelled against human control. It contacted other sandminers and "converted" the Super-Vocs on board to its cause. It was destroyed by a human investigator before its plans proceeded too far — but the investigator did not live to report his findings, being accidentally "disassembled" by Vocs who believed him to be a malfunctioning SV. (COMIC: Crisis on Kaldor)
Technology
The robots were physically stronger and more durable than most humans. It was generally assumed that fundamental protocols in the brains of the robots made it impossible for them to knowingly harm humans, although a robotics genius such as Taren Capel could override this precaution. The robots recognised their authorised controllers via their voice prints. A change in the controller's vocal pattern could result in apparently rebellious behaviour and non-compliance from a robot. All robots were identified by their class letter and a unique number; for example a Voc might be "named" V7. (TV: The Robots of Death)
Standard robot classes
Dum
The majority of the robots were D-class Dums, built without the ability to speak. On a sandminer, the Dums mostly kept to the engineering decks, away from the human crew, making them appear less common than was the case. Dums wore dark green tunics. D84, a highly sophisticated Super-Voc class robot, was disguised as a Dum. (TV: The Robots of Death)
Voc
More able were the V-class Voc robots, who had the power of speech. In the absence of humans, Vocs performed essential control deck duties on a sandminer and were capable of running the vehicle without supervision. They could give back massages to human crew. They wore green tunics. (TV: The Robots of Death)
Super-Voc
Each sandminer's complement of robots included one SV-class Super-Voc, which had enhanced decision-making and organisational skills. The Super-Voc was effectively the leader of the robots, though still subservient to any of the authorised human crew. The Super-Voc wore a silver tunic. (TV: The Robots of Death)
Unique robots
Ultra-Voc
Only one UV-class Ultra-Voc was ever manufactured, an even more intelligent and autonomous version of the standard SV. It is not known what colour it was designated. (COMIC: Crisis on Kaldor)
SASV1
SASV1 was another unique robot, an attempt to improve on a specialised SV class unit numbered D84. [disputed statement] However, SASV-1 was based on plans drawn up by Taren Capel and proved mentally unstable. (PROSE: Corpse Marker)