# Environmental feedback with ballistic properties

**URL:** <http://discourse.iapct.org/t/environmental-feedback-with-ballistic-properties/15717>\
**Category:** Experimental Findings\
**Created:** [November 10, 2020, 10:38pm UTC](http://discourse.iapct.org/t/environmental-feedback-with-ballistic-properties/15717 "2020-11-10T22:38:10Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**Author:** ![rsmarken](http://discourse.iapct.org/user_avatar/discourse.iapct.org/rsmarken/32/3553_2.png) [@rsmarken](http://discourse.iapct.org/u/rsmarken)\
**Post date:** [November 11, 2020, 1:40am UTC](http://discourse.iapct.org/t/environmental-feedback-with-ballistic-properties/15717/2 "2020-11-11T01:40:51Z")

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[quote=“bnhpct, post:1, topic:15717, full:true”]  
In his personal introduction, Patrick Smith described his research interest:

> [@Patrick Smith Introduction](http://discourse.iapct.org/t/patrick-smith-introduction/15714/1):
>
> I am an experimental behavioral psychologist working on human motor performance and learning … My current research has participants attempting the same putt A LOT …

> BN: Other examples include archery, skeet shooting, and navigation by dead reckoning.

RM: Archery and skeet shooting, yes; like putting, both have a ballistic (uncontrolled) component of the control loop between output and its effect on the controlled variable. Not so, however, with navigation by dead reckoning, which involves continuous control of a variable (one’s angle relative to a point on shore), very much like controlling optical angles when catching a fly ball.

> BN: Is this amenable to a similar approach as in the _Exp. Brain Res._ paper “Sensorimotor delays in tracking may be compensated by negative feedback control of motion-extrapolated position” as recently discussed in the [Delay in control loops](http://discourse.iapct.org/t/delay-in-control-loops/15691) topic?

RM: I don’t think so. There is no ballistic component in the tracking task; there is continuous control of the controlled variable (T - C + dT/dt). The extrapolation component of the controlled variable, dT/dt, helps out to the extent that the change in target position at t+tau is highly correlated with the change at t, which it is with sinusoidal target movement. The best you can do with a putt is cognitively compute the likely trajectory of the ball after it’s been hit.

RM: You really have no control over the ball after it has been struck by the putter (or the arrow has been released or the trigger has been pulled). All the actual control that’s happening in putting (archery and skeet shooting) occurs before the ballistic component of the behavior is set in motion. And a lot of it occurs in imagination before the shot is made (such as calculating the predicted effect of the slope and wetness of the green on the ball’s trajectory). Once all those calculations are made there must be control of the angle and force of the putter on the ball.

Best Rick

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