Comments from Forum Member 'justintm036'
I have a Prakttissmate PK1 so I can share my experience.As Marco stated, it’s not the easiest when it comes to adjustments. That’s the price you pay for its powerful capability. There are so many degrees of freedom it’s hard to imagine going smoothly from one type of shot to another quickly. However, if it’s your own robot you will come up with ways to make things easier for yourself. I use it for exercise as well as practicing strokes so may be what I do is more limited. Still I only practice one type of stroke at a time. For me the robot may stay at one setting for a long time. I do vary within a setting as explained below.
I chose a 2-wheel robot, one that can recreate a realistic shot, believing that it would make the transition from robot to human a bit easier. I could hardly counterloop my practice partner’s loop but once I set up the PK1 to mimic his loop, after a bit of practice we can do it 4-5 times in a row. We don’t have the consistency of the robot so we put the ball in the wrong place, limiting the rally, but still a lot of fun.
Head height: You can get a small wooden stick and make markings on it to help you get back to a setting quickly. To adjust the height just loosen a knob and move the head up or down.
Head tilt: It either shoots the ball into the net or off the table. I hold the head with the right hand, unlock the head with the left hand and tilt the head up and down a bit. Takes a few seconds.
Initially I kept notes of all the settings but now no longer refer to them since I vary around a setting anyway. I make markings on the remote control (red magic marker, stickers etc…) to help see at a glance. The PK1 robot has a larger wheel and a smaller wheel. The larger wheel only rotates in one direction, the smaller wheel is reversible and can rotate forward or backward.
For topspin I leave the larger wheel on top (producing topspin). The smaller wheel at the bottom is set in the forward position, produces backspin and adds to the forward throwing force. I set the smaller wheel roughly in the middle of the speed range I normally use e.g. 3.5, then bring the speed of the larger wheel up till the ball lands at the right distance and practice from there.
I aim the robot at myself during setup to block the ball with the paddle while adjusting the wheels. Aiming takes a couple of seconds; you turn off the feed wheel, adjust the directional control and turn the feed wheel back on. If I lengthen the landing by adjusting only the larger wheel, the ball will land farther but may have too much topspin, so I make it a little bit shorter than I want then add the remaining distance with the smaller wheel.
Using landing distance as a guide, you can change spin and speed easily in a matter of seconds. Again, block and twiddle. At a given setting, I aim the robot at various places BH and FH and practice from there.
To change setup to underspin I stop the robot, set the smaller wheel to e.g. 4.5 and adjust the larger wheel for the correct landing. Again varying a bit from there. I found the strokes to be the same within a range of spin and speed; I adjust to the ball bounce and trajectory.
To setup heavy spin slow loops - the kind where you see the ball scaringly going over the net slowly but flies off when you touch it – I set the smaller wheel to 0 and reverse, and set the larger wheel to land the ball at the right place. In reverse, the smaller wheel adds topspin to the ball while decreasing the forward throwing force. Then I increase the speed of the smaller wheel, the landing will shorten as the spin increases. I add more topspin from the larger wheel to make the landing correct and practice from there.
For each setting I can practice floating the ball back, punch blocking or counter looping. Then aim to the FH and practice etc… So there are a lot of things to do at one setting. I also use it for exercise so run around FH and BH like mad.
To do sidespin I just rotate the heads 90 degrees one way or the other – with the larger wheel to the left or to the right; takes seconds. To do no spin, I set it to do sidespin first (for a better visual feedback), then depending on whether the ball curves left or right I adjust the left or right knob. I know from experience which one to adjust so it takes only a few seconds, again blocking the ball while twiddling the knob.
Anyway, just sharing how I use the robot. Hope it is of some help.
Marco Replies
This post is wonderful. I think you should get together with Prakktismate and help them to write their next edition of their manual.For clarity, instead of saying "backspin" wheel you should say "smaller wheel" and also indicate in which direction you are using the "smaller wheel" since that is the one that is reversible. The bigger wheel only travels in one direction. It would also be helpful if you indicate the location of the bigger wheel (i.e. top, bottom, left side while staring at the robot, right side while staring at the robot).
Again, excellent post. You seem to have developed some techniques for making PK1 usage much easier. For example, you mentioned setting the smaller wheel at a certain rate and then adjusting the bigger wheel from there. I often did the reverse, I started with the big wheel at a certain speed and then tried to adjust the smaller wheel. Often this resulted in me spending a lot of time (up to 5 minutes) to get the desired ball. I will try your way next time.
I know I am tough on a robot because I'm trying to set up very precise balls. I want serves that are very low and short, or I'm trying to set up precise "finger-breaker" half-long serves that are also low; or I'm trying to set up long serves that nearly hit the white line. And I am trying to change from one type to the next rapidly. I know I'm asking a lot of any robot.
