Ordered to Hit a Homerun on the First and Only Chance at Bat

--- When you talk about equipment to be used in space, you are talking about one-of-a-kind devices, aren't you? This must be true especially if your goal is scientific observation or technology development. Yokota: Yes.--- And that's why you deliver only of each piece of equipment, which is required to be no less than perfect. Yokota: Right again.--- In baseball, no matter how skillful a batter you are, there would be incredible pressure if you were ordered to hit a homerun on your first and only chance at bat. Yokota: But you can wait for the third pitch. In the case of the GLI, we created two prototypes: the BBM (Breadboard Model) and the EM (Engineering Model). The third model, the PFM (Proto Flight Model) was the one sent into space.--- So you shot the third ball into the stands. (Laughs) What does "Breadboard" mean? Iwai: That's the board that bakers use to knead bread dough, but it also means an experimental model used to test the feasibility of a new product or device. The EM looks very much like the PFM and was used to thoroughly examine performance, durability and production methods. Even though the PFM has the word "Proto" in its name, it actually became the Flight Model.--- The environment in outer space is extremely harsh. First of all, you have the vacuum... Yokota: The environment is actually beneficial for optical equipment. Without any disturbances caused by air, the GLI can provide clearer images.--- What about weightlessness? Iwai: Zero gravity doesn't present a problem in and of itself, but the fact that we constructed the GLI on earth, where there is gravity, presented some complexity. The production people on-site faced considerable difficulties here.--- What do you mean? Iwai: Objects bend or warp under their own weight when gravity is present. No matter how light or durable an object might be, the level of bending can be reduced, but bending itself can't be prevented. But such bending doesn't occur in a weightless environment. In general, the ideal is to produce and adjust an object under conditions as close as possible to the environment in which it will be used.
Assembly and ajustments of the GLI

Assembly and adjustments were made using numerous support pillars.
--- But, unfortunately, Canon doesn't yet have an orbital facility. (Laughs) Iwai: Unfortunately, no. (Laughs) When assembling the GLI, we used as many support structures as we could for the main unit, canceled out warping by precisely adjusting the force on this unit, and maintained an environment as close as possible to zero gravity. (See photo.) The overall balance, and level of warping, would change every time a new component was added. Each time this happened, we used a collimator (optical device for forming an infinitely distant virtual image that can be viewed without parallax) or other instrument to make detailed adjustments before adding the next component.--- Add a part, measure and adjust. Add another part, measure and adjust... Iwai: That would be the best way to explain the difficulties we faced at the production site.