Home RISC OS material present in this section

  BeebControl>>Robot arms>>Armdroid

     Arms | Armdroid | Siblings | Manual | Drawings | Software | Links | Gallery  

Exploded drawing of Armdroid limbs Armdroid history notes

Armdroid I and II models were designed and built by Colne Robotics Limited, originally of Beaufort Road, East Twickenham, Middlesex, UK.

The first Armdroids were available in kit form or finish-built and included a hand-held control pendant. The kit version was made popular by construction articles in Electronics Today International (ETI) magazive during 1981.
Initially, Armdoids featured two stacked circuit boards in the base with connections for both computer and pendant control. These models are relatively common as they accounted for about the first third of Armdroid production. They can be recognized by the presence of bare, edge connection tracks projecting into the two side cutouts in the base. Later Armdroid I and II models used a single circuit board with a 10-pin IDC connector present at the wider slot - the other narrow slot was empty as the control pendant had by now been dropped. A software driver program to suit a range of 8-bit micros was provided with the Armdoid I and this was 'improved' for the launch of the later Armdroid II.

According to a former Colne electronics/software developer, Armdroids have even starred in a number of low budget movies, including one classic called 'Inseminator' (don't ask). The link to that info is now dead but, thanks to the magic of the Wayback Machine's Web archive, I've located a copy of the original text and put it in the Armdroid 'Siblings' section, as it relates to the Labvolt and D&M derivatives too.
Watch out. There's 5000 Armdroids out there somewhere!

A press release from Hasfield Systems - subsequent makers of the Armdroid - claims it had a production run of ten years and worldwide sales of over 5,000 before being replaced by an uprated, PC based version called 'Bidroid'. In fact it was referred to as 'Birdroid' throughout a pre-production press release in a publication called Teaching Technology. Whether Hasfield Systems changed their minds prior to Bidroid's launch, or whether it was just an editorial error, we'll never know. It did look a bit like a bird though.
Armdroid I (see right) was driven largely by Kevlar cords and was notoriously tricky to set up if the cords were broken, missing or displaced - particularly so if a manual wasn't available. Armdroid II replaced the Kevlar cords with miniature toothed timing belts and incorporated a number of other improvements over its predecessor.

An upgrade process from I to II was available from Colne. Genuine two-tone Armdroid IIs however are very rare and most Armdroids encountered are likely to be of the earlier design (or upgraded).

In addition to the UK, the Armdroid was also marketed in North America and became popular in colleges there. So much so that when Colne Robotics went out of business in the UK, their American affiliate, D&M Computing, took up manufacture and produced the Armdroid 1000 - essentially an all-blue cosmetically rebranded Armdroid II. Like Colne Robotics, D&M Computing has been out of business for some time now - bought up in the late 1990s by Lab-Volt Inc. However Lab-Volt have continued the Armdroid line (but not the name) with new PC based models that include a top-of-the-line servo motor version.
Armdroid I
The original 8-bit Armdroid is a passively motorised device - it possesses no CPU or electronic control capability of its own, relying instead on outside computing power (e.g. a BBC B micro) to supply the correct sequence of pulses to drive its stepper motors. Armdroid's on-board circuitry merely translates low-level input pulses into the correct voltage and current levels required to drive each motor in the chosen direction. One advantage of this simple configuration is that the user can experiment with different pulse sequences, speed rates and ramping to suit their particular needs. For instance, Colne were able to improve positional control and stepping rates for Armdroid II simply by rewriting the software program.
Exploded drawing of Armdroid fingers Getting a grip

Armdroid's gripper arrangement was unique in its day, thanks to its patented three-finger design. The three jointed fingers had a spookily animal quality when operated slowly - like a hand with three thumbs.

A more conventional, two-finger model was also available and was fitted as standard to many US derivatives. The two finger model suited rectangular objects while the three finger gripper was ideal for spheres or cylindrical shapes.

<< Arms
All content on this website is Neil Fazakerley or its originators