DODonHopkins·Sep 12, 2026
Lars Brinkhoff suggests that this thread comp.lang.logo with Brian Harvey and Leigh Klotz is required reading:
https://escholarship.org/uc/item/1623m1p3
https://news.ycombinator.com/item?id=36755727
larsbrinkhoff on July 17, 2023 [–]
A list of all Logo memos, with links where I could find them.
https://github.com/pdp11/sits/wiki/List-of-Logo-memos
https://news.ycombinator.com/item?id=28605037
larsbrinkhoff on Sept 21, 2021 | next [–]
Your LLOGO copy was for an older version of Maclisp, but eventually we (Eric and I) managed to port it over to New IO. It works fine and displays on an emulated Knight TV. (Itself a tour de force in emulation: the TV PDP-11 code runs on an emulator sharing its Unibus with the PDP-10 emulator.)
We also have an early PDP-11 Logo, an even earlier BBN PDP-10 Logo, and a later Apple II Logo (not the Terrapin versi
Read the rest
on). I also wrote an emulator for the General Turtle 2500 computer slash terminal.
DonHopkins on Sept 21, 2021 | parent | next [–]
Do you have the specs for the infamous military Terrapin Snapping Turtle proposed to the Department of Defense?
https://dl.acm.org/doi/10.1145/1056602.1056608
https://donhopkins.com/home/TurtlesAndDefense.pdf
>TURTLES AND DEFENSE
>Introduction
>At Terrapin, we feel that our two main products, the Terrapin Turtle ®, and the Terrapin Logo Language for the Apple II, bring together the fields of robotics and AI to provide hours of entertainment for the whole family. We are sure that an enlightened application of our products can uniquely impact the electronic battlefield of the future. [...]
>Guidance
>The Terrapin Turtle ®, like many missile systems in use today, is wire-guided. It has the wire-guided missile's robustness with respect to ECM, and, unlike beam-riding missiles, or most active-homing systems, it has no radar signature to invite enemy missiles to home in on it or its launch platform. However, the Turtle does not suffer from that bugaboo of wire-guided missiles, i.e., the lack of a fire-and-forget capability.
>Often ground troops are reluctant to use wire-guided antitank weapons because of the need for line-of-sight contact with the target until interception is accomplished. The Turtle requires no such human guidance; once the computer controlling it has been programmed, the Turtle performs its mission without the need of human intervention. Ground troops are left free to scramble for cover. [...]
>Because the Terrapin Turtle ® is computer-controlled, military data processing technicians can write arbitrarily baroque programs that will cause it to do pretty much unpredictable things. Even if an enemy had access to the programs that guided a Turtle Task Team ® , it is quite likely that they would find them impossible to understand, especially if they were written in ADA. In addition, with judicious use of the Turtle's touch sensors, one could, theoretically, program a large group of turtles to simulate Brownian motion. The enemy would hardly attempt to predict the paths of some 10,000 turtles bumping into each other more or less randomly on their way to performing their mission. Furthermore, we believe that the spectacle would have a demoralizing effect on enemy ground troops. [...]
>Munitions
>The Terrapin Turtle ® does not currently incorporate any munitions, but even civilian versions have a downward-defense capability. The Turtle can be programmed to attempt to run over enemy forces on recognizing them, and by raising and lowering its pen at about 10 cycles per second, puncture them to death.
>Turtles can easily be programmed to push objects in a preferred direction. Given this capability, one can easily envision a Turtle discreetly nudging a hand grenade into an enemy camp, and then accelerating quickly away. With the development of ever smaller fission devices, it does not seem unlikely that the Turtle could be used for delivery of tactical nuclear weapons. [...]